The active compounds 6-gingerol and 6-shogaol exhibit anti-cancer properties against the gastrointestinal tract and helps in cancer cell death. Garlic is another most important spice that is used in treating cancer.

It has the ability to inhibit the production of cancer-causing properties, speed up the repairing process of DNA and to decelerate the proliferation of cancer cells.

Black pepper contains anti-oxidant piperine. A study conducted in Michigan's cancer institute concluded that the black pepper along with turmeric can prevent the growth of cancerous stem cells in breast tumours. This aromatic herb used inn pizzas contain an active ingredient known as carvacrol, which is proven to be beneficial in treating prostate cancers.

The oregano oil has the ability to selectively kill the cancer cells while leaving the healthy cells intact. BUDG ET ' Mutual Funds.

More Menu. These observations from recent systematic reviews and meta-analyses, as well as more recent epidemiologic studies that have not yet been included in such reviews, are summarized below.

A recent meta-analysis of 19 case—control and two cohort studies showed that consumption of large amounts of total Allium vegetables reduced risk of gastric cancer when comparing the highest and lowest consumption groups [odds ratio OR , 0. Results were similar for individual Allium vegetables, including garlic, onion, leeks, Chinese chives, scallions, and garlic stalks, but not onion leaves.

Their summary OR was 0. They also conducted meta-analyses of two cohort studies that investigated total Allium vegetables and cancer, which produced a summary effect estimate of 0.

They concluded that due to consistent evidence, dose—response relationship, and plausible mechanisms, a cancer-preventive relationship between Allium vegetables and vegetables was probable 1.

Investigators with the European Prospective Investigation into Cancer and Nutrition EPIC study were unable to corroborate the findings of the above meta-analyses.

After 6. However, after 11 years of follow-up and cases, even this weak association was no longer evident for total gastric adenocarcinoma. Allium vegetables were also not associated with decreased risk of cardia, noncardia, intestinal, and diffuse subtypes of gastric cancer The EPIC cohort, which included men and women of ages 35 to 70 years recruited from —, had relatively high fruit and vegetable consumption even in the lowest quintile of intake, thus making it difficult to compare high with low or no intake.

A meta-analysis of eight different prospective cohort studies on total Allium vegetable intake and colorectal cancer risk showed no decrease in risk with increased Allium consumption Other case—control evidence has been suggestive of benefit. In a network of Italian and Swiss case—control studies that included 1, cases and 2, controls, intake of onions and garlic was assessed separately via food frequency questionnaire The investigators found that both onions and garlic were protective against cancers of the large bowel.

Intermediate and high garlic use were associated with decreased risk of colorectal cancer with ORs of 0. In this study, subjects were classified into no, low, intermediate, and high usage categories for both onions and garlic based on two questions included in a food frequency questionnaire.

No information of preparation or cooking of the vegetables was available, nor was information on whether subjects were taking garlic supplements. The association of onion and garlic intake on colorectal adenoma was also assessed using cases and 5, controls from subjects in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial Investigators assessed onion and garlic intake collectively for the 12 months before screening using a food frequency questionnaire.

Cooked garlic or onions were not addressed in this study. Only one of the case—control studies showed a statistically significant decrease in risk. Both garlic OR, 0. The Italian and Swiss case—control networks study showed that those with the highest intake of both onions and garlic did not have significantly decreased OR of prostate cancer compared with those with the lowest intake OR onions , 0.

A third study, using data from the Vitamins And Lifestyle cohort, analyzed the association of garlic supplements on prostate cancer risk and found that garlic supplement use was not associated with a decreased risk of prostate cancer among men in western Washington state HR, 1.

In addition, one to seven servings of onions per week was associated with significantly decreased odds of laryngeal OR, 0. No significant associations were observed for onions or garlic and breast cancer or for onions and renal cell carcinoma. A study of cases from the Hawaii Tumor Registry and controls randomly selected from a list of Oahu residents found that onions OR, 0.

When lung cancer subtypes were considered, onions were more strongly associated with decreased risk of squamous cell carcinoma OR, 0. Additional analyses of data from the EPIC cohort found that after 9 years of follow-up, garlic and onions combined had no effect on cervical carcinoma in situ or on invasive squamous cervical cancer Epidemiologic studies provide variable evidence for cancer-preventive activities of garlic, onions, and related Allium vegetables, with stronger evidence for prevention of cancers of the gastrointestinal tract, including gastric, colorectal, and to some extent esophageal cancers.

However, not all individuals respond to increased consumption, based on a host of factors including genetics, preparation of the vegetables, or other dietary components. Body composition, previous history of cancer or precancerous conditions, or other cancer risk factors likely also contribute to determining those who will respond the most.

In addition, other factors including epigenetic modifications and variability in the gut microbiome, currently largely unexplored in studies on associations between Allium intake and cancer risk, may also influence responses.

Epidemiologic studies are powerful tools for determining associations with cancer risk in large populations. However, these studies have limitations, including multiple testing and potential for false discovery.

In addition, studying associations with Allium vegetables proves to be particularly challenging due to the difficulty in assessment of intake levels.

The common use of quantiles in epidemiologic studies makes it difficult to compare results across studies, as many cohorts have different ranges of Allium or total vegetable intake. Improved methods for assessment of intake of garlic and onions may help to further clarify the relationship between these vegetables and cancer risk.

Few intervention studies have examined the efficacy of dietary or supplemental Allium vegetables in cancer prevention. Incidence of neither total nor gastric cancer decreased significantly in the overall study population after 5 years, though the combined intervention resulted in a relative risk for all tumors of 0.

Another randomized multi-intervention trial in Shandong, China, tested the efficacy of mg garlic extract plus 4 mg steam-distilled garlic oil daily to inhibit progression of precancerous gastric lesions After 7.

Further intervention studies are warranted to overcome the confounding issues of epidemiologic analysis of Allium vegetables and cancer risk, including accurate assessment of intake and separation of effects of garlic and onions.

Mechanistic studies provide compelling evidence that garlic, onions, and their sulfur components alter the biologic behavior of tumors, tumor microenvironments, or precancerous cells, and decrease cancer risk. No animal studies have examined whole Allium vegetables, though multiple garlic preparations and compounds have demonstrated efficacy against carcinogenesis in preclinical rodent models.

DATS, DADS, DAS, SAC, ajoene, garlic powder, and garlic extracts reviewed in refs. Cancer protection by Allium vegetables may arise from several mechanisms, detailed below. It is probable that several of these cellular events are modified simultaneously.

Nitrosamines and heterocyclic amines HCA are potential dietary carcinogens that are not normally present in foods but may arise during preservation or cooking Evidence points to the ability of allyl sulfur compounds to suppress the spontaneous and bacterial mediated formation of nitrosamines 44 , although not all allyl sulfur compounds prevent nitrosamine formation equally.

SAC and its analog S-propyl cysteine, but not DADS, dipropyl disulfide, or DAS, retarded nitrosamine formation, suggesting a critical role for a cysteine residue in inhibition Furthermore, water extracts of garlic, deodorized garlic powder, and onion, but not leeks, decreased nitrosamine formation The reduction in nitrosamine formation may be a result of increased formation of nitrosothiols, as sulfur compounds might reduce nitrite availability for nitrosamine formation In humans, ingesting 5 g of garlic per day completely blocked the enhanced urinary excretion of nitrosoproline, an indicator for the synthesis of potentially carcinogenic nitrosamines, which occurred as a result of ingesting supplemental nitrate and proline More recent evidence suggests that as little as 1 g of garlic may be sufficient to suppress nitrosoproline formation Allium allyl sulfur compounds are also effective in blocking DNA alkylation, an early step in nitrosamine carcinogenesis Consistent with this reduction in bioactivation, Dion and colleagues 45 found that both water-soluble SAC and lipid-soluble DADS blocked nitrosomorpholine mutagenicity in Salmonella typhimurium TA A block in nitrosamine bioactivation may arise from inactivation of cytochrome P 2E1 CYP2E1; refs.

Inhibition of CYP2E1 by an autocatalytic destruction mechanism may account for some of the chemoprotective effects of DAS and potentially other allyl sulfur compounds Fluctuations in the content and overall activity of CYP2E1 may be an important variable in determining the magnitude of the protection provided by garlic and associated allyl sulfur components.

HCAs arise from surfaces of well-done meats Garlic powder reduced levels of MeIQx and PhIP by In a study testing the ability of oil marinades containing various levels of onion, garlic, and lemon juice to inhibit HCA formation, increasing garlic and onion, but not lemon juice, in the marinades significantly decreased the formation of MeIQx.

The concentrations of onion, garlic, and lemon that led to the maximal MeIQx reduction were Once ingested, HCAs are bioactivated by N-oxidation via cytochrome PA2, N-acetyltransferases NAT , and sulfotransferases, to electrophilic species that are much more reactive with DNA than HCAs are.

Yu and colleagues 56 demonstrated that a suppression in NAT mRNA expression accounts for the majority of the reduction in the activity of garlic. Platt and colleagues 57 demonstrated that onion juice inhibited the genotoxicity of the HCA 2-aminomethylimidazo{4,5- f }quinoline in genetically engineered metabolically active Chinese hamster lung fibroblasts with IC 50 of 0.

Garlic extracts and compounds reduced the incidence of tumors resulting from the carcinogen N-nitroso-N-methylurea MNU; ref. SAC and DADS in the diet decreased MNU-induced O6-methylguanine adducts bound to mammary cell DNA in rats DAS diminished the DNA hypermethylation of esophagus, liver, and nasal mucosa that arose from treatment with N-nitrosomethylbenzylamine However, Cohen and colleagues 63 reported that SAC did not protect against MNU-induced mammary tumors.

The reason for this discrepancy is unknown but may be reflective of the proportion of lipid in the diet or the dose of carcinogen given. If garlic and onion compounds are indeed effective blockers of carcinogenicity of these compounds, the mechanism s remain unresolved.

The role of organosulfur compounds in biotransformation may be substrate-specific. The observed protection from garlic and onions may also involve other enzymes involved in the bioactivation or removal of carcinogenic metabolites.

Singh and colleagues 64 provided evidence that the efficacy of various organosulfides to suppress benzo a pyrene tumorigenesis was correlated with their ability to induce NAD P H:quinone oxidoreductase NQO1 , an enzyme involved with the removal of quinones associated with this carcinogen.

This inductive effect appears to be mediated by the antioxidant response element enhancer sequence bound by the nuclear factor E2-related factor 2 Nrf2 in the NQO1 and the heme oxygenase 1 HO1 gene promoters. DAS, DADS, and DATS all differentially mediated the transcriptional levels of NQO1 and HO1, with DATS having the strongest effect Phase II detoxification, specifically changes in glutathione concentration and the activity of specific glutathione- S -transferases GST , may also be important in the protection provided by garlic and onions.

Both DADS and DATS increased the activity of GST in a variety of rat tissues Garlic also protected against aflatoxin carcinogenesis in rats via induction of GST A5 levels For example, DADS-suppressed Cdk1 activity during cell-cycle arrest in G 2 —M that was associated with a temporal and dose-dependent increase in cyclin B1 protein level, a reduction in the level of Cdk1—cyclin B1 complex formation, an inactivation of Cdk1 by hyperphosphorylation, and a decrease in Cdc25C protein level Further gene expression analysis suggested that alterations in DNA repair and cellular adhesion factors may also be involved in the G 2 —M block following DADS exposure Current knowledge of the mechanisms by which these compounds cause apoptosis indicates that they target various apoptotic signaling molecules from initiation to execution.

However, in many studies, the apoptotic effects of sulfur compounds were triggered by increased intracellular production of reactive oxygen species ROS , suggesting the importance of the intracellular redox environment for induction of apoptosis.

For example, DATS increased hydrogen peroxide formation, lowered thiol levels, and induced caspase-3 activity in HepG2 cells Substantial evidence indicates that garlic extracts can inhibit a range of Gram-negative and Gram-positive bacteria, and serve as antifungal agents Various sulfur compounds including allicin, DAS, DADS, and ajoene derivatives may contribute to garlic's antimicrobial properties Garlic's inhibitory effect against the bacteria Helicobacter pylori is of note as H.

pylori colonization of the gastric mucosa is linked with gastritis and a greater propensity to develop gastric cancer. pylori proliferation. Both DAS and DADS elicited a dose-dependent depression in H. pylori proliferation in culture Raw garlic extracts and three commercially available garlic tablets varied in their efficacy against H.

pylori , as indicated by minimum inhibitory concentrations in the range between 10 to The ability of garlic to reduce H. pylori infection in humans is inconclusive.

Although an epidemiologic study suggested an association between increased garlic consumption and reduced H. pylori infection 78 , two clinical studies that tested different garlic preparations in H. pylori infected subjects did not show efficacy 79, Neither of these interventions resulted in the elimination of the organism, change in the severity of gastritis, or a significant change in symptom scores.

Both studies were not randomized and had small sample sizes, suggesting that a well-designed clinical trial is still needed to determine the efficacy of garlic consumption in reducing H. pylori infection and symptoms. Specifically, the antimicrobial action of allicin and its breakdown products has been suggested to be due to its rapid interaction with SH-containing molecules, including amino acids and cellular proteins within microbial organisms Changes in thiol status have been suggested as one possible mechanism by which garlic and related sulfur compounds might also suppress tumor proliferation.

Some, but not all, Allium organosulfur compounds have reported antioxidant properties. Alliin and allicin possessed antioxidant properties in a Fenton oxygen-radical generating system DADS, but not DAS, dipropyl sulfide or dipropyl disulfide, inhibited liver microsomal lipid peroxidation induced by NADPH, ascorbate, and doxorubicin The presence of both the allyl and sulfur groups appears to magnify the antioxidant capabilities of the molecule.

Both the number of sulfur atoms and the oxidation state of sulfur atoms can influence the overall antioxidant potential Garlic oil was also effective antioxidant against oxidative damage caused by various agents 85 , indicating that lipid-soluble organosulfur compounds can also be effective antioxidants.

Although some ether extracted garlic oil preparations in the marketplace may contain about nine times as much vinyldithiins and four times as much ajoene as crushed fresh garlic, these preparations had no free radical scavenging properties, again indicating not all organosulfur constituents have antioxidant properties Allium vegetables also contain a wide variety of other antioxidant compounds including flavonoids, glutathione, selenium compounds, and vitamins E and C.

Nuutila and colleagues found that the scavenging activities of onion and garlic extracts correlated with the total phenolic content. Onions had higher radical scavenging activities than garlic, red onions had higher activities than yellow onions, and outer portions of onion bulbs had higher activities than inner portions Although limited, there is some evidence that Allium -associated sulfur components can inhibit cyclooxygenase COX and lipoxygenase activities 87, DAS, DADS, and, to a lesser extent, AMS differentially regulated nitric oxide, prostaglandin E2 PGE2 , and cytokine production in mouse macrophages stimulated by lipopolysaccharide LPS; ref.

Similar to several nonsteroidal anti-inflammatory drugs, ajoene inhibited the release of PGE2 from LPS-activated RAW Garlic, onions, and their extracts and compounds may also have immunomodulatory effects.

Both an aqueous and ethanolic extract of garlic powder significantly stimulated proliferation of rat spleen lymphocytes in culture. This correlated with the upregulation of interleukin-2 IL2 receptor-α expression and an increase in IL2 production The effect of the extracts on lymphocyte proliferation in vitro differed depending on the specific stimulator of cell proliferation.

It is possible that cancer cells may gain some unique metabolic properties for being targeted uniquely by the garlic compounds. But so far the experimental data is rare in supporting such a scenario.

Some gain-of-function changes of cancer cells have been identified. But however, none of these changed functions was exclusive to cancer cells as normal cells also have them only at somewhat lowered levels. For example, all cancer cells show highly elevated cell division that also shared by some normal cells.

The non-selective cytotoxic effects on the rapidly growing hair follicle cells and GI tract epithelial cells by many chemotherapy compounds are the reasons for hair loss and bad GI tract reactions.

To establish such a gain-of-function targeting mechanism for the selectivity, one has to first find such a novel target that is present only in all cancer cells and is absent from all normal cells.

So far, no such a cancer marker matches all these criteria. However, an opposite scenario for such an absolute selectivity is highly feasible. We would like to propose one possible mechanism to explain the selective cancer killing.

The garlic compounds may target one or more loss-of-function pathways in cancer cells. In these cases, the nutrients that can be easily processed metabolically in the normal cells cannot be processed in the cancer cells owing to their defective pathways of metabolism.

Any nutrient that can be up-taken by the cells but cannot be processed metabolically would be accumulated intracellularly and become cytotoxic. Cancer cells are well known to be the metabolically streamlined cells in which many metabolic pathways become defective in comparison to their normal cell counterparts.

For example, nearly all cancer cells are defective in pathways related to mitochondria functions 32 , In addition, hepatoma cells of rat or human are also defective in lipid methylation pathways 34 , 35 , Other vegetables and fruits, such as cauliflower, red grape, guava, and strawberry also showed similar anticancer properties, but, unlike RGE, the extents of their activities varied from cancer cell lines to lines.

Nevertheless, we believe that the extracts from these raw vegetables and fruits may also work better via injection than ingestion for their anticancer activities.

There is no indication so far that these activities were additive when the different extracts were combined together. It also came to our attention that RGE produced from different geological regions may have different potencies of anticancer property.

It is not clear whether the differences were due to differences in subspecies of garlic or the soil qualities for the garlic growth. Further investigations seem to be needed. The identification of the active compounds in RGE is underway.

But it may be complicated by the fact that the activity may involve multiple compounds concertedly in RGE. However, with or without identification of specific active compounds first, RGE as a food can be used safely in animals and humans as the parenteral nutrients via intravenous or ip injection without the concern of cytotoxicity to normal cells.

Although microbes cannot survive in RGE, it is reasonable to filter the preparations through the 0. All 22 fruits and vegetables, including raw garlic, were purchased from the local supermarket of Winston-Salem, North Carolina, USA.

All the dilution factors in the final solutions were calculated by the folds of dilution from the original wet weights of the individual fruits and vegetables. A portion of the garlic extracts was centrifuged through a spin-filter unit Amicon Ultra After centrifugation, RGE was separated into three phases: a colorless upper aqueous phase; a white solid interphase; and a light-yellowish lower organic phase.

The aqueous phase and organic phase were collected carefully. The aqueous phase was dried with a gentle stream of nitrogen gas to remove the methanol and brought up with PBS to the original volume before phase separation.

J82 and human bladder cancer cells, Hela human cervix cancer cell, K human myelogenous leukemia cell, EL4 murine musculus lymphoma cell, and S murine sarcoma cell were purchase from American Type Tissue Culture Collection. Twenty-four hours after the cancer cell ip injection day 0 , mice were divided into the groups of the designed treatments and untreated controls.

The mice were inspected and weighted daily for the assessment of ascites development. All of the animal research procedures were approved by the Institutional Animal Care and Use Committee. The nm absorbance was measured in an automatic microplate reader.

Cellular morphology was analyzed and photographed under the light microscope. The survival percentages were performed with GraphPad Prism version 5 GraphPad Software, San Diego, CA.

Shashikant, K. Studies on the antimicrobial and stimulatory factors of garlic Allium sativum Linn. Food Sci. Google Scholar. Rode, H. The antimicrobial effect of Allium sativum L.

Kim, J. Effect of heat treatments on the antimicrobial activities of garlic Allium sativum. Adetumbi, M. Alliumsativum garlic —a natural antibiotic. Hypotheses 12 , — Article CAS Google Scholar. Kyung, K. Antimicrobial properties of allium species.

Al Waili, N. et al. Effects of heating, storage, and ultraviolet exposure on antimicrobial activity of garlic juice. Food 10 , — Nicastro, H. Garlic and onions: their cancer prevention properties.

Cancer Prev. Warshafsky, S. Effect of garlic on total serum cholesterol: a meta-analysis. Yeh, Y. Cholesterol-lowering effect of garlic extracts and organosulfur compounds: human and animal studies. Silagy, C. Garlic as a lipid lowering agent--a meta-analysis. Physicians Lond. CAS PubMed Google Scholar.

Thomson, M. Including garlic in the diet may help lower blood glucose, cholesterol, and triglycerides. Block, E. The chemistry of garlic and onions.

Ali, M. Consumption of a garlic clove a day could be beneficial in preventing thrombosis. Prostaglandins Leukot.

Fatty Acids 53 , — Gebreyohannes, G. Medicinal values of garlic: a review. Tattelman, E. Health effects of garlic. Physician 72 , — PubMed Google Scholar.

Murray, M. Prima Pub. Press, California, Guercio, V. Food Res. Zhou, Y. Consumption of large amounts of Allium vegetables reduces risk for gastric cancer in a meta-analysis. Gastroenterology , 80—89 Kodali, R. Meta-analysis: does garlic intake reduce risk of gastric cancer?

Cancer 67 , 1—11 Turati, F. Colorectal cancer and adenomatous polyps in relation to allium vegetables intake: A meta-analysis of observational studies. Woo, H. Diet and cancer risk in the Korean population: a meta-analysis.

Asian Pac. Article Google Scholar. Chiavarini, M. Garlic consumption and colorectal cancer risk in man: a systematic review and meta-analysis. Public Health Nutr. Zhu, B. Allium vegetables and garlic supplements do not reduce risk of colorectal cancer, based on meta-analysis of prospective studies.

Milner, J. Mechanisms by which garlic and allyl sulfur compounds suppress carcinogen bioactivation. Garlic and carcinogenesis. Bom, J. Based Complementary Altern. Boivin, D. Antiproliferative and antioxidant activities of common vegetables: a comparative study.

For total garlic and onion intake, women in the highest tertile of consumption had an adjusted odds ratio OR for breast cancer when compared to the lowest tertile of 0. For those in the medium consumption category, the OR was 0.

When the cohort was stratified by menopausal status, some differences emerged. The OR for the highest consumption group compared with the lowest group among premenopausal women was 0. Among postmenopausal women, though, the OR among the highest consumption group was 0. Gauri Desai, Michelle Schelske-Santos, Cruz M.

Nazario, Rosa V. Rosario-Rosado, Imar Mansilla-Rivera, Farah Ramírez-Marrero, Jing Nie, Ajay A. Myneni, Zuo-Feng Zhang, Jo L. Phase 3 Trial of Trilaciclib in Triple-Negative Breast Cancer Will Continue.

The final overall survival analysis of trilaciclib plus chemotherapy in patients with metastatic triple-negative breast cancer as part of the PRESERVE 2 trial will take place in the third quarter of Strategy for Reducing Obesity May Mitigate Advanced Breast Cancer Diagnoses.

Screening frequency appears to be a weak risk factor for advanced breast cancer, with obesity in post-menopausal and dense breasts in pre-menopausal patients being more prominent factors.

Tucatinib plus trastuzumab emtansine shows a progression-free survival improvement in HER2-positive breast cancer in the phase 3 HER2CLIMB trial, says Sara A. Hurvitz, MD, FACP. FDA Receives New Drug Application for SH in Breast and Ovarian Cancer.

The FDA has set a Prescription Drug User Fee Act date of June 29, for SH as a treatment for patients with ovarian cancer or breast cancer. Data from the phase 2 A-PLUS trial indicate that bevacizumab plus chemotherapy prior to whole brain radiotherapy may be an efficacious systemic strategy for intractable brain and extracranial metastases stemming from breast cancer.

Clinical Topics. Global Bulletin. All News. Approval Alert. Around the Practice. Between the Lines. Face Off. Morning Rounds. Readout Sponsored Media. Training Academy. Treatment Algorithms with the Oncology Brothers.

All Journals. Editorial Board. For Authors. Frontline Forum. Satellite Sessions. Contemporary Concepts. Awareness Month. Interactive Tools. The results in Fig. Survived cells were measured by CCK To determine the solubility of the anticancer property, we partitioned RGE into the organic phase and aqueous phase via chloroform extraction.

Instead of having the anticancer property, the aqueous phase of RGE even stimulated the growth of S and especially K human leukemia cells to onefold more than RGE.

The aqueous phase and organic phase of RGE were prepared as described in the section of methods. To examine the mechanisms of the induced cancer cell death, S cells after being treated by various RGE preparations were examined morphologically.

After treated by RGE or the organic phase, all S cells showed the highly condensed cellular and nucleus morphology, being consistent with apoptosis Fig. The aqueous phase and organic phase of RGE were prepared as described in the methods section.

As a flavoring food, garlic is often ingested after cooking. Many studies of the anticancer properties were also done with the cooked garlic. These results indicate that some anticancer activities of RGE were heat-labile and others were heat-resistant. Our results showed that the injected RGE had no adverse effect on the treated animals, indicating that RGE did not harm normal cells.

We wanted to further verify this ability of RGE to distinguish cancer cells from normal cells in the in vitro system. We isolated human polymorphic nucleus PMN cells from the blood of healthy donors. Human PMN and human cervical carcinoma Hela cells were co-cultured with RGE at different dilutions.

At or higher dilutions of RGE, there was no specific cytotoxicity against PMN or Hela Fig. At or lower dilutions nearly all Hela cells were killed and most PMN were alive. The apparent selectivity against cells in vitro was in an agreement to that of the in vivo results of the injected RGE.

The major finding of our study is that RGE had a novel therapeutic effect against even the most aggressive models of malignancy in mice only when injected. Ingestion of the same amount of RGE failed to offer any meaningful effect on the same model of malignancy. This novel anticancer activity in the mouse models was also recapitulated in the cell culture in which the direct cancer cell killing by RGE stood out far better than the extract from any other 21 vegetables and fruits.

This activity was contributable to the multiple garlic compounds that were partially heat-sensitive, organic-soluble and smaller than Dalton. The treated mice did not display any adverse side-effect in terms of behavior and physical appearance from receiving daily injections of RGE.

Necropsy also failed to find any abnormality in any organ and tissue of the treated mice either from the malignancies or from the injected RGE. One novel aspect of the injected RGE was its ability to cure the most aggressive mouse cancer models that cannot be cured by any conventional therapy.

Historically, there have been two major types of modeling cancer in mice for drug testing. The most popular model is to transplant human cancer cells into the mice, to form visible nodules, and to test the effects of drugs on the nodule sizes. The other model, although rarely used nowadays, was to transplant aggressive cancer cells that induce rapid lethality and to test the effects of agents on the survival of the mice.

So far, there has not been any report of any conventional therapy to be successful in curing this type of the induced mouse malignancy and effectively rescued the mice from death. The two mouse models used in this study represented this second type of malignancy with the extreme aggressiveness in which the survival times, if treated unsuccessfully, are between 13 and 15 days.

The mice in these types of malignancy underwent cachexia, internal bleeding, and the failure of major organs that, unlike the first model, represent all the terminal events of human cancer deaths. Therefore, the ability of the injected RGE to completely kill all the cancer cells without any adverse side-effect in mice may represent one of the most potent anticancer properties reported so far, giving the hopes of significant beneficial effects if being used in humans.

Another surprising aspect of our findings was the complete opposite effects of RGE injection in comparison with ingestion. This novel finding showed that the extremely potent anticancer activity of RGE was only achieved by direct exposure to cancer cells and was completely lost by going first through the GI tract.

Given the fact that garlic is a flavoring food, one can safely reason that all the compounds in garlic are the unharmful nutrients to the normal cells and can be taken even in large quantity by humans without adverse side-effect.

Ingestion is a process in which all the nutrients in the food must be absorbed first into the epithelial cells of the GI tract walls.

Before being released into the bloodstream, some nutrients have to be processed or modified metabolically in the epithelial cells. This process apparently destroyed all the anticancer property of the ingested RGE in addition to the possibility that the digestive enzymes and acidity in the cavities of stomach and intestines may also be destructive to the anticancer activity.

Although very simple, the profound anticancer property of the injected RGE has not been reported in the literature. Nearly, all the garlic studies were done with the ingested garlic or injections of individually isolated garlic compounds.

However, injection of raw food juice or parenteral nutrients to cancer patients who are still capable of normal eating is rarely practiced in the clinical settings. The anticancer therapeutic potential of normal nutrients from fruits and vegetables without being first processed by the intestinal epithelial cells may have never been tested.

Yet, this study also showed that many other raw fruits and vegetables also had significant anticancer properties when directly exposed to cancer cells. Therefore, injection of raw food juices may represent a new concept of treatment and may provide novel therapeutic potentials in comparison to ingestion of food after cooking.

Our results also showed that the killing of cancer cells but not normal cells by RGE was highly specific. This selective killing of cancer cells was also reflected in the treated mice that had neither visible physical side-effect nor abnormality in any organ or tissue upon necropsy.

This selectivity must be based on the intrinsic yet common differences between many, if not all, cancer cells and normal cells. It is possible that cancer cells may gain some unique metabolic properties for being targeted uniquely by the garlic compounds. But so far the experimental data is rare in supporting such a scenario.

Some gain-of-function changes of cancer cells have been identified. But however, none of these changed functions was exclusive to cancer cells as normal cells also have them only at somewhat lowered levels.

For example, all cancer cells show highly elevated cell division that also shared by some normal cells. The non-selective cytotoxic effects on the rapidly growing hair follicle cells and GI tract epithelial cells by many chemotherapy compounds are the reasons for hair loss and bad GI tract reactions.

To establish such a gain-of-function targeting mechanism for the selectivity, one has to first find such a novel target that is present only in all cancer cells and is absent from all normal cells. So far, no such a cancer marker matches all these criteria. However, an opposite scenario for such an absolute selectivity is highly feasible.

We would like to propose one possible mechanism to explain the selective cancer killing. The garlic compounds may target one or more loss-of-function pathways in cancer cells. In these cases, the nutrients that can be easily processed metabolically in the normal cells cannot be processed in the cancer cells owing to their defective pathways of metabolism.

Any nutrient that can be up-taken by the cells but cannot be processed metabolically would be accumulated intracellularly and become cytotoxic. Cancer cells are well known to be the metabolically streamlined cells in which many metabolic pathways become defective in comparison to their normal cell counterparts.

For example, nearly all cancer cells are defective in pathways related to mitochondria functions 32 , In addition, hepatoma cells of rat or human are also defective in lipid methylation pathways 34 , 35 , Other vegetables and fruits, such as cauliflower, red grape, guava, and strawberry also showed similar anticancer properties, but, unlike RGE, the extents of their activities varied from cancer cell lines to lines.

Nevertheless, we believe that the extracts from these raw vegetables and fruits may also work better via injection than ingestion for their anticancer activities.

There is no indication so far that these activities were additive when the different extracts were combined together.

It also came to our attention that RGE produced from different geological regions may have different potencies of anticancer property.

It is not clear whether the differences were due to differences in subspecies of garlic or the soil qualities for the garlic growth. Further investigations seem to be needed.

The identification of the active compounds in RGE is underway. But it may be complicated by the fact that the activity may involve multiple compounds concertedly in RGE. However, with or without identification of specific active compounds first, RGE as a food can be used safely in animals and humans as the parenteral nutrients via intravenous or ip injection without the concern of cytotoxicity to normal cells.

Although microbes cannot survive in RGE, it is reasonable to filter the preparations through the 0. All 22 fruits and vegetables, including raw garlic, were purchased from the local supermarket of Winston-Salem, North Carolina, USA.

All the dilution factors in the final solutions were calculated by the folds of dilution from the original wet weights of the individual fruits and vegetables. A portion of the garlic extracts was centrifuged through a spin-filter unit Amicon Ultra After centrifugation, RGE was separated into three phases: a colorless upper aqueous phase; a white solid interphase; and a light-yellowish lower organic phase.

The aqueous phase and organic phase were collected carefully. The aqueous phase was dried with a gentle stream of nitrogen gas to remove the methanol and brought up with PBS to the original volume before phase separation. J82 and human bladder cancer cells, Hela human cervix cancer cell, K human myelogenous leukemia cell, EL4 murine musculus lymphoma cell, and S murine sarcoma cell were purchase from American Type Tissue Culture Collection.

Twenty-four hours after the cancer cell ip injection day 0 , mice were divided into the groups of the designed treatments and untreated controls.

The mice were inspected and weighted daily for the assessment of ascites development. All of the animal research procedures were approved by the Institutional Animal Care and Use Committee. The nm absorbance was measured in an automatic microplate reader. Cellular morphology was analyzed and photographed under the light microscope.

The survival percentages were performed with GraphPad Prism version 5 GraphPad Software, San Diego, CA. Shashikant, K. Studies on the antimicrobial and stimulatory factors of garlic Allium sativum Linn.

Food Sci. Google Scholar. Rode, H. The antimicrobial effect of Allium sativum L. Kim, J. Effect of heat treatments on the antimicrobial activities of garlic Allium sativum.

Adetumbi, M. Alliumsativum garlic —a natural antibiotic. Hypotheses 12 , — Article CAS Google Scholar. Kyung, K. Antimicrobial properties of allium species. Al Waili, N. et al. Effects of heating, storage, and ultraviolet exposure on antimicrobial activity of garlic juice.

Food 10 , — Nicastro, H. Garlic and onions: their cancer prevention properties. Cancer Prev. Warshafsky, S. Effect of garlic on total serum cholesterol: a meta-analysis.

Yeh, Y. Cholesterol-lowering effect of garlic extracts and organosulfur compounds: human and animal studies. Silagy, C. Garlic as a lipid lowering agent--a meta-analysis. Physicians Lond.

CAS PubMed Google Scholar. Thomson, M. Including garlic in the diet may help lower blood glucose, cholesterol, and triglycerides. Block, E. The chemistry of garlic and onions. Ali, M. Consumption of a garlic clove a day could be beneficial in preventing thrombosis.

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Meta-analysis: does garlic intake reduce risk of gastric cancer? Cancer 67 , 1—11 Turati, F. Colorectal cancer and adenomatous polyps in relation to allium vegetables intake: A meta-analysis of observational studies.

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Garlic and carcinogenesis. Bom, J. Based Complementary Altern. Boivin, D. Antiproliferative and antioxidant activities of common vegetables: a comparative study. Food Chem.

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Cancer Ther. Jasamai, M.

Cinnamon is well-known for its health benefits, including its ability to reduce blood sugar and ease inflammation 16 , In addition, some test-tube and animal studies have found that cinnamon may help block the spread of cancer cells.

A test-tube study found that cinnamon extract was able to decrease the spread of cancer cells and induce their death Another test-tube study showed that cinnamon essential oil suppressed the growth of head and neck cancer cells, and also significantly reduced tumor size An animal study also showed that cinnamon extract induced cell death in tumor cells, and also decreased how much tumors grew and spread However, more studies are needed to understand how cinnamon may affect cancer development in humans.

Summary Test-tube and animal studies have found that cinnamon extract may have anticancer properties and may help decrease the growth and spread of tumors. More research in humans is needed.

Research has found that eating nuts may be linked to a lower risk of certain types of cancer. For instance, a study looked at the diets of 19, people and found that eating a greater amount of nuts was associated with a decreased risk of dying from cancer Another study followed 30, participants for up to 30 years and found that eating nuts regularly was associated with a decreased risk of colorectal, pancreatic and endometrial cancers For example, Brazil nuts are high in selenium, which may help protect against lung cancer in those with a low selenium status These results suggest that adding a serving of nuts to your diet each day may reduce your risk of developing cancer in the future.

Still, more studies in humans are needed to determine whether nuts are responsible for this association, or whether other factors are involved.

Summary Some studies have found that an increased intake of nuts may decrease the risk of cancer. Research shows that some specific types like Brazil nuts and walnuts may also be linked to a lower risk of cancer.

Several studies have even found that a higher intake of olive oil may help protect against cancer. One massive review made up of 19 studies showed that people who consumed the greatest amount of olive oil had a lower risk of developing breast cancer and cancer of the digestive system than those with the lowest intake Another study looked at the cancer rates in 28 countries around the world and found that areas with a higher intake of olive oil had decreased rates of colorectal cancer Swapping out other oils in your diet for olive oil is a simple way to take advantage of its health benefits.

You can drizzle it over salads and cooked vegetables, or try using it in your marinades for meat, fish or poultry. Though these studies show that there may be an association between olive oil intake and cancer, there are likely other factors involved as well. More studies are needed to look at the direct effects of olive oil on cancer in people.

Summary Several studies have shown that a higher intake of olive oil may be associated with a reduced risk of certain types of cancer. Turmeric is a spice well-known for its health-promoting properties. Curcumin, its active ingredient, is a chemical with anti-inflammatory, antioxidant and even anticancer effects.

One study looked at the effects of curcumin on 44 patients with lesions in the colon that could have become cancerous.

In a test-tube study, curcumin was also found to decrease the spread of colon cancer cells by targeting a specific enzyme related to cancer growth Another test-tube study showed that curcumin helped kill off head and neck cancer cells Curcumin has also been shown to be effective in slowing the growth of lung, breast and prostate cancer cells in other test-tube studies 30 , 31 , Use it as a ground spice to add flavor to foods, and pair it with black pepper to help boost its absorption.

Summary Turmeric contains curcumin, a chemical that has been shown to reduce the growth of many types of cancer and lesions in test-tube and human studies. Eating citrus fruits such as lemons, limes, grapefruits and oranges has been associated with a lower risk of cancer in some studies.

One large study found that participants who ate a higher amount of citrus fruits had a lower risk of developing cancers of the digestive and upper respiratory tracts A review looking at nine studies also found that a greater intake of citrus fruits was linked to a reduced risk of pancreatic cancer These studies suggest that including a few servings of citrus fruits in your diet each week may lower your risk of developing certain types of cancer.

More studies are needed on how citrus fruits specifically affect cancer development. Summary Studies have found that a higher intake of citrus fruits could decrease the risk of certain types of cancers, including pancreatic and stomach cancers, along with cancers of the digestive and upper respiratory tracts.

Some research has shown that it may even help decrease cancer growth and help kill off cancer cells. In one study, 32 women with breast cancer received either a flaxseed muffin daily or a placebo for over a month. At the end of the study, the flaxseed group had decreased levels of specific markers that measure tumor growth, as well as an increase in cancer cell death In another study, men with prostate cancer were treated with flaxseed, which was found to reduce the growth and spread of cancer cells Flaxseed is high in fiber, which other studies have found to be protective against colorectal cancer 7 , 8 , 9.

Try adding one tablespoon 10 grams of ground flaxseed into your diet each day by mixing it into smoothies, sprinkling it over cereal and yogurt, or adding it to your favorite baked goods.

Summary Some studies have found that flaxseed may reduce cancer growth in breast and prostate cancers. It is also high in fiber, which may decrease the risk of colorectal cancer.

Lycopene is a compound found in tomatoes that is responsible for its vibrant red color as well as its anticancer properties. Several studies have found that an increased intake of lycopene and tomatoes could lead to a reduced risk of prostate cancer.

A review of 17 studies also found that a higher intake of raw tomatoes, cooked tomatoes and lycopene were all associated with a reduced risk of prostate cancer Another study of 47, people found that a greater intake of tomato sauce, in particular, was linked to a lower risk of developing prostate cancer To help increase your intake, include a serving or two of tomatoes in your diet each day by adding them to sandwiches, salads, sauces or pasta dishes.

Summary Some studies have found that a higher intake of tomatoes and lycopene could reduce the risk of prostate cancer. However, more studies are needed. The active component in garlic is allicin, a compound that has been shown to kill off cancer cells in multiple test-tube studies 40 , 41 , Several studies have found an association between garlic intake and a lower risk of certain types of cancer.

One study of , participants found that those who ate lots of Allium vegetables, such as garlic, onions, leeks and shallots, had a lower risk of stomach cancer than those who rarely consumed them A study of men showed that a higher intake of garlic was associated with a reduced risk of prostate cancer Another study found that participants who ate lots of garlic, as well as fruit, deep yellow vegetables, dark green vegetables and onions, were less likely to develop colorectal tumors.

However, this study did not isolate the effects of garlic Based on these findings, including 2—5 grams approximately one clove of fresh garlic into your diet per day can help you take advantage of its health-promoting properties.

However, despite the promising results showing an association between garlic and a reduced risk of cancer, more studies are needed to examine whether other factors play a role. Summary Garlic contains allicin, a compound that has been shown to kill cancer cells in test-tube studies. Studies have found that eating more garlic could lead to decreased risks of stomach, prostate and colorectal cancers.

Some research suggests that including a few servings of fish in your diet each week may reduce your risk of cancer. One large study showed that a higher intake of fish was associated with a lower risk of digestive tract cancer Another study that followed , adults found that eating more fish decreased the risk of developing colorectal cancer, while red and processed meats actually increased the risk In particular, fatty fish like salmon, mackerel and anchovies contain important nutrients such as vitamin D and omega-3 fatty acids that have been linked to a lower risk of cancer.

For example, having adequate levels of vitamin D is believed to protect against and reduce the risk of cancer In addition, omega-3 fatty acids are thought to block the development of the disease Aim for two servings of fatty fish per week to get a hearty dose of omega-3 fatty acids and vitamin D, and to maximize the potential health benefits of these nutrients.

Still, more research is needed to determine how fatty fish consumption may directly influence the risk of cancer in humans. Summary Fish consumption may decrease the risk of cancer.

Fatty fish contains vitamin D and omega-3 fatty acids, two nutrients that are believed to protect against cancer. As new research continues to emerge, it has become increasingly clear that your diet can have a major impact on your risk of cancer.

Although there are many foods that have potential to reduce the spread and growth of cancer cells, current research is limited to test-tube, animal and observational studies. More studies are needed to understand how these foods may directly affect cancer development in humans.

Read this article in Spanish. Our experts continually monitor the health and wellness space, and we update our articles when new information becomes available. This article is based on scientific evidence, written by experts and fact checked by experts. A block in nitrosamine bioactivation may arise from inactivation of cytochrome P 2E1 CYP2E1; refs.

Inhibition of CYP2E1 by an autocatalytic destruction mechanism may account for some of the chemoprotective effects of DAS and potentially other allyl sulfur compounds Fluctuations in the content and overall activity of CYP2E1 may be an important variable in determining the magnitude of the protection provided by garlic and associated allyl sulfur components.

HCAs arise from surfaces of well-done meats Garlic powder reduced levels of MeIQx and PhIP by In a study testing the ability of oil marinades containing various levels of onion, garlic, and lemon juice to inhibit HCA formation, increasing garlic and onion, but not lemon juice, in the marinades significantly decreased the formation of MeIQx.

The concentrations of onion, garlic, and lemon that led to the maximal MeIQx reduction were Once ingested, HCAs are bioactivated by N-oxidation via cytochrome PA2, N-acetyltransferases NAT , and sulfotransferases, to electrophilic species that are much more reactive with DNA than HCAs are.

Yu and colleagues 56 demonstrated that a suppression in NAT mRNA expression accounts for the majority of the reduction in the activity of garlic. Platt and colleagues 57 demonstrated that onion juice inhibited the genotoxicity of the HCA 2-aminomethylimidazo{4,5- f }quinoline in genetically engineered metabolically active Chinese hamster lung fibroblasts with IC 50 of 0.

Garlic extracts and compounds reduced the incidence of tumors resulting from the carcinogen N-nitroso-N-methylurea MNU; ref. SAC and DADS in the diet decreased MNU-induced O6-methylguanine adducts bound to mammary cell DNA in rats DAS diminished the DNA hypermethylation of esophagus, liver, and nasal mucosa that arose from treatment with N-nitrosomethylbenzylamine However, Cohen and colleagues 63 reported that SAC did not protect against MNU-induced mammary tumors.

The reason for this discrepancy is unknown but may be reflective of the proportion of lipid in the diet or the dose of carcinogen given.

If garlic and onion compounds are indeed effective blockers of carcinogenicity of these compounds, the mechanism s remain unresolved.

The role of organosulfur compounds in biotransformation may be substrate-specific. The observed protection from garlic and onions may also involve other enzymes involved in the bioactivation or removal of carcinogenic metabolites.

Singh and colleagues 64 provided evidence that the efficacy of various organosulfides to suppress benzo a pyrene tumorigenesis was correlated with their ability to induce NAD P H:quinone oxidoreductase NQO1 , an enzyme involved with the removal of quinones associated with this carcinogen.

This inductive effect appears to be mediated by the antioxidant response element enhancer sequence bound by the nuclear factor E2-related factor 2 Nrf2 in the NQO1 and the heme oxygenase 1 HO1 gene promoters. DAS, DADS, and DATS all differentially mediated the transcriptional levels of NQO1 and HO1, with DATS having the strongest effect Phase II detoxification, specifically changes in glutathione concentration and the activity of specific glutathione- S -transferases GST , may also be important in the protection provided by garlic and onions.

Both DADS and DATS increased the activity of GST in a variety of rat tissues Garlic also protected against aflatoxin carcinogenesis in rats via induction of GST A5 levels For example, DADS-suppressed Cdk1 activity during cell-cycle arrest in G 2 —M that was associated with a temporal and dose-dependent increase in cyclin B1 protein level, a reduction in the level of Cdk1—cyclin B1 complex formation, an inactivation of Cdk1 by hyperphosphorylation, and a decrease in Cdc25C protein level Further gene expression analysis suggested that alterations in DNA repair and cellular adhesion factors may also be involved in the G 2 —M block following DADS exposure Current knowledge of the mechanisms by which these compounds cause apoptosis indicates that they target various apoptotic signaling molecules from initiation to execution.

However, in many studies, the apoptotic effects of sulfur compounds were triggered by increased intracellular production of reactive oxygen species ROS , suggesting the importance of the intracellular redox environment for induction of apoptosis.

For example, DATS increased hydrogen peroxide formation, lowered thiol levels, and induced caspase-3 activity in HepG2 cells Substantial evidence indicates that garlic extracts can inhibit a range of Gram-negative and Gram-positive bacteria, and serve as antifungal agents Various sulfur compounds including allicin, DAS, DADS, and ajoene derivatives may contribute to garlic's antimicrobial properties Garlic's inhibitory effect against the bacteria Helicobacter pylori is of note as H.

pylori colonization of the gastric mucosa is linked with gastritis and a greater propensity to develop gastric cancer. pylori proliferation.

Both DAS and DADS elicited a dose-dependent depression in H. pylori proliferation in culture Raw garlic extracts and three commercially available garlic tablets varied in their efficacy against H. pylori , as indicated by minimum inhibitory concentrations in the range between 10 to The ability of garlic to reduce H.

pylori infection in humans is inconclusive. Although an epidemiologic study suggested an association between increased garlic consumption and reduced H. pylori infection 78 , two clinical studies that tested different garlic preparations in H.

pylori infected subjects did not show efficacy 79, Neither of these interventions resulted in the elimination of the organism, change in the severity of gastritis, or a significant change in symptom scores. Both studies were not randomized and had small sample sizes, suggesting that a well-designed clinical trial is still needed to determine the efficacy of garlic consumption in reducing H.

pylori infection and symptoms. Specifically, the antimicrobial action of allicin and its breakdown products has been suggested to be due to its rapid interaction with SH-containing molecules, including amino acids and cellular proteins within microbial organisms Changes in thiol status have been suggested as one possible mechanism by which garlic and related sulfur compounds might also suppress tumor proliferation.

Some, but not all, Allium organosulfur compounds have reported antioxidant properties. Alliin and allicin possessed antioxidant properties in a Fenton oxygen-radical generating system DADS, but not DAS, dipropyl sulfide or dipropyl disulfide, inhibited liver microsomal lipid peroxidation induced by NADPH, ascorbate, and doxorubicin The presence of both the allyl and sulfur groups appears to magnify the antioxidant capabilities of the molecule.

Both the number of sulfur atoms and the oxidation state of sulfur atoms can influence the overall antioxidant potential Garlic oil was also effective antioxidant against oxidative damage caused by various agents 85 , indicating that lipid-soluble organosulfur compounds can also be effective antioxidants.

Although some ether extracted garlic oil preparations in the marketplace may contain about nine times as much vinyldithiins and four times as much ajoene as crushed fresh garlic, these preparations had no free radical scavenging properties, again indicating not all organosulfur constituents have antioxidant properties Allium vegetables also contain a wide variety of other antioxidant compounds including flavonoids, glutathione, selenium compounds, and vitamins E and C.

Nuutila and colleagues found that the scavenging activities of onion and garlic extracts correlated with the total phenolic content. Onions had higher radical scavenging activities than garlic, red onions had higher activities than yellow onions, and outer portions of onion bulbs had higher activities than inner portions Although limited, there is some evidence that Allium -associated sulfur components can inhibit cyclooxygenase COX and lipoxygenase activities 87, DAS, DADS, and, to a lesser extent, AMS differentially regulated nitric oxide, prostaglandin E2 PGE2 , and cytokine production in mouse macrophages stimulated by lipopolysaccharide LPS; ref.

Similar to several nonsteroidal anti-inflammatory drugs, ajoene inhibited the release of PGE2 from LPS-activated RAW Garlic, onions, and their extracts and compounds may also have immunomodulatory effects. Both an aqueous and ethanolic extract of garlic powder significantly stimulated proliferation of rat spleen lymphocytes in culture.

This correlated with the upregulation of interleukin-2 IL2 receptor-α expression and an increase in IL2 production The effect of the extracts on lymphocyte proliferation in vitro differed depending on the specific stimulator of cell proliferation.

Garlic powder extracts also modulated proliferation of rat thymocytes and splenocytes in response to concanavalin A in vitro. At higher concentrations, the extracts had an inhibitory effect on T-cell proliferation but lower concentrations of extracts resulted in an increase in T-cell proliferation.

For centuries, Allium vegetables have been used in a wide variety of cuisines worldwide and are valued for their potential medicinal properties. During the first Olympic Games in Greece, garlic was consumed as a stimulant and in Roman times, soldiers chewed garlic before battle for strength.

Presently, these vegetables continue to hold their fascination for their unique flavor, chemistry, and biologic properties. Epidemiologic studies indicate some protective associations of Allium vegetable consumption against cancers, particularly cancers of the gastrointestinal tract.

However, difficulties in assessing Allium consumption hamper efforts to further define these effects. If garlic consumption does reduce the risk of cancer, the amount needed to lower risk remains unknown.

Intervention studies have potential to overcome challenges present in epidemiologic studies. Mechanistic studies indicate potential mechanisms of the anticancer activity of various Allium vegetable extracts and preparations, and highlight the activities of the sulfur-containing compounds.

These compounds have effects at each stage of carcinogenesis and affect many physiologic processes that modify cancer risk. Several research gaps exist. Further research is warranted to improve methods for assessment of consumption of Allium vegetables for epidemiologic studies.

Furthermore, the effect of Allium vegetables on cancer processes cannot be considered in isolation; rather, they are likely dependent on several environmental and dietary variables. Dietary factors that have shown effect modification include total fat, selenium, methionine, and vitamin A Other factors that may influence the relationship of Allium vegetables and cancer prevention are the interactions of these foods and their constituents with the oral and gut microbiota 93, In addition, the contribution of Allium vegetables to thiol signaling is an emerging area in redox biology that requires further study Finally, determining those who will respond most to increased consumption and determining the optimal amount s and preparation s of Allium vegetables for cancer prevention will aid the scientific community in making public health recommendations for garlic and onion consumption.

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Skip Nav Destination Close navigation menu Article navigation. Volume 8, Issue 3. Next Article. Bioactive Compounds.

Epidemiologic Studies on Allium Vegetables and Cancer Risk. Intervention Studies. Possible Mechanisms. Disclosure of Potential Conflicts of Interest.

Article Navigation. Review March 05 Garlic and Onions: Their Cancer Prevention Properties Holly L. Nicastro ; Holly L. Nicastro, National Heart, Lung, and Blood Institute, Rockledge Dr , Bethesda, MD Phone: ; Fax: ; E-mail: holly.

nicastro nih. This Site. Google Scholar. Sharon A. Ross ; Sharon A. John A. Milner John A. Received: July 25 Revision Received: November 25 Accepted: December 15 Online ISSN: Cancer Prev Res Phila 8 3 : — Article history Received:. Revision Received:. Cite Icon Cite. toolbar search Search Dropdown Menu.

toolbar search search input Search input auto suggest. Figure 1. View large Download slide. Table 1. Energy, kcal 40 72 30 61 Protein, g 6.

View Large. Figure 2. No potential conflicts of interest were disclosed. Food, nutrition, physical activity, and the prevention of cancer: a global perspective.

Gastric cancer and allium vegetable intake: a critical review of the experimental and epidemiologic evidence. Search ADS.

Modulatory influence of garlic and tomato on cyclooxygenase-2 activity, cell proliferation and apoptosis during azoxymethane induced colon carcinogenesis in rat. Food and Agriculture Organization of the United Nations Statistics Division [cited May 12, ].

Onions: The Sweet Smell of Success. Agricultural Outlook October Economic Research Service USDA 5—8. Department of Agriculture, Agricultural Research Service. Characterization of shortday onion cultivars of 3 pungency levels with flavor precursor, free amino acid, sulfur, and sugar contents.

Identification and HPLC quantitation of the sulfides and dialk en yl thiosulfinates in commercial garlic products. HPLC analysis of allicin and other thiosulfinates in garlic clove homogenates. Volatile sulfur compounds in human expiration after eating raw or heat-treated garlic. Composition, stability, and bioavailability of garlic products used in a clinical trial.

Effect of processing and cooking conditions on onion Allium cepa L. induced antiplatelet activity and thiosulfinate content. Allicin and allicin-derived garlic compounds increase breath acetone through allyl methyl sulfide: use in measuring allicin bioavailability.

In vivo metabolism of diallyl disulphide in the rat: identification of two new metabolites. Consumption of large amounts of Allium vegetables reduces risk for gastric cancer in a meta-analysis. Fruit and vegetable intake and the risk of stomach and oesophagus adenocarcinoma in the European Prospective Investigation into Cancer and Nutrition EPIC-EURGAST.

Dietary factors and in situ and invasive cervical cancer risk in the European prospective investigation into cancer and nutrition study. Allium vegetables and garlic supplements do not reduce risk of colorectal cancer, based on meta-analysis of prospective studies. Fruit and vegetable intake and prevalence of colorectal adenoma in a cancer screening trial.

Food intake and the occurrence of squamous cell carcinoma in different sections of the esophagus in Taiwanese men. Specialty supplements and prostate cancer risk in the VITamins and Lifestyle VITAL cohort. Le Marchand. Vitamin, mineral, and specialty supplements and risk of hematologic malignancies in the prospective VITamins And Lifestyle VITAL study.

Effects of aged garlic extract AGE on colorectal adenomas: a double-blinded study. An intervention study to prevent gastric cancer by micro-selenium and large dose of allitridum. A factorial trial including garlic supplements assesses effect in reducing precancerous gastric lesions.

Fifteen-year effects of Helicobacter pylori, garlic, and vitamin treatments on gastric cancer incidence and mortality. Molecular mechanisms and targets of cancer chemoprevention by garlic-derived bioactive compound diallyl trisulfide.

Development of a food database of nitrosamines, heterocyclic amines, and polycyclic aromatic hydrocarbons. Mechanisms by which garlic and allyl sulfur compounds suppress carcinogen bioactivation.

Garlic and carcinogenesis. The blocking effect of garlic on the formation of N-nitrosoproline in humans. A gas chromatography-mass spectrometry method for the quantitation of N-nitrosoproline and N-acetyl-S-allylcysteine in human urine: application to a study of the effects of garlic consumption on nitrosation.

Diallylsulfide and allylmethylsulfide are uniquely effective among organosulfur compounds in inhibiting CYP2E1 protein in animal models. Mechanisms of inhibition of chemical toxicity and carcinogenesis by diallyl sulfide DAS and related compounds from garlic. Metabolism of the chemoprotective agent diallyl sulfide to glutathione conjugates in rats.

Plant extracts, spices, and essential oils inactivate Escherichia coli OH7 and reduce formation of potentially carcinogenic heterocyclic amines in cooked beef patties. Influence of natural food ingredients on the formation of heterocyclic amines in fried beef patties and chicken breasts.

Effect of oil marinades with garlic, onion, and lemon juice on the formation of heterocyclic aromatic amines in fried beef patties. Fruits and vegetables protect against the genotoxicity of heterocyclic aromatic amines activated by human xenobiotic-metabolizing enzymes expressed in immortal mammalian cells.

Garlic and associated allyl sulfur components inhibit N-methyl-N-nitrosourea induced rat mammary carcinogenesis. Chemoprevention of aberrant crypt foci in the colon of rats by dietary onion. Modulation of N-nitrosomethylbenzylamine bioactivation by diallyl sulfide in vivo.

S-allylcysteine, a garlic constituent, fails to inhibit N-methylnitrosourea-induced rat mammary tumorigenesis. Differential induction of NAD P H:quinone oxidoreductase by anti-carcinogenic organosulfides from garlic. Induction of detoxifying enzymes by garlic organosulfur compounds through transcription factor Nrf2: effect of chemical structure and stress signals.

Relative activities of organosulfur compounds derived from onions and garlic in increasing tissue activities of quinone reductase and glutathione transferase in rat tissues.

Comparison of the chemopreventive efficacies of garlic powders with different alliin contents against aflatoxin B1 carcinogenicity in rats. Signal transduction pathways leading to cell cycle arrest and apoptosis induction in cancer cells by Allium vegetable-derived organosulfur compounds: a review.

Possible mechanism by which allyl sulfides suppress neoplastic cell proliferation. Diallyl disulfide inhibits p34 cdc2 kinase activity through changes in complex formation and phosphorylation.

The effects of garlic-derived sulfur compounds on cell proliferation, caspase 3 activity, thiol levels and anaerobic sulfur metabolism in human hepatoblastoma HepG2 cells.