Legumes – Beans, Lentils and Peas – Help Prevent Cancer
The evidence is mounting that legumes, which include beans, peas and lentils, fight cancer in a serious way. This also includes bean sprouts. Research has confirmed that legumes reduce a myriad of cancer types with several mechanisms.
Let’s survey some of the latest research evidence.
Legumes reduce cancer deaths
A 2018 study from several universities and Spain’s Centro de Investigación Biomédica en Red Fisiopatologia de la Obesidad y la Nutrición (CIBEROBN) followed 7,216 people for an average of six years. The researchers analyzed their diets, and in particular, their consumption of legumes – including dry beans, chickpeas, lentils and fresh peas.
The researchers found that those who ate more legumes had a half the number of cancer deaths compared to those who ate fewer legumes. Yes, they found a 49 percent lower incidence of death from cancer by eating more legumes.
Beans boost colorectal cancer survival
A 2016 study from the University of Colorado School of Medicine tested 37 patients who survived colorectal cancer. For four weeks, they gave the patients a regimen of 35 grams of navy beans or 30 grams of rice bran, along with a control group that ate neither.
The researchers found those who consumed the navy beans had longer telomere lengths and significantly lower levels of inflammation. They concluded these patients had a greater survival potential as a result of their navy bean consumption.
A 2014 study from Mexico’s Universidad Autónoma de Querétaro found that bean proteins inhibited human colorectal cancer cells.
We’ve also shown research proving that nuts also fight colorectal cancers.
Anti-cancer lectins in beans
Don’t believe the hype suggesting that lectins are bad for you. (We’ve discussed the health benefits of lectins in other articles.) The reality is that lectins boost our immunity and help our bodies fight cancer and viruses.
Multiple studies have investigated lectins in beans that have specific anti-cancer effects. For example, in a 2018 study, researchers from Japan’s Kibi International University tested Japanese red sword beans (Canavalia gladiata) for anti-cancer properties. They found the beans contain a particular lectin that significantly boosts the immune system’s ability to fight cancer.
They found the RSB lectin boosted interleukin-2 and inhibited melanoma cancer cells from growing.
A 2016 study from the University of Hong Kong tested another bean lectin. This one from the white kidney bean (Phaseolus vulgaris). The researchers found that the white kidney bean lectin inhibited breast cancer and sinus cancer cells.
Mung beans combat several cancers
A 2018 study from Babol University of Medical Sciences found that mung bean proteins inhibited human breast cancer cells, cervical cancer cells, and skin cancer cells.
They also found that the mung bean proteins help prevented radiation damage to skin cells. This means they help guard against sunburn-related skin cancers.
Black beans fight breast cancer
A 2017 study from the All India Institute of Medical Sciences found that black turtle beans (or black beans) have anti-cancer properties. The researchers tested the bean extracts against two types of human breast cancer cells. They found the extracts inhibited the growth of breast cancer cells. They also found the bean extracts killed many cancer cells (apoptosis) outright.
This ability to kill cancer cells occurred by the bean extracts damaging the mitochondria and producing DNA fragmentation in the cancer cells.
Common beans inhibit cancers
In a 2016 study, researchers from Italy’s CREA institute analyzed twelve different varieties of common beans (Phaseolus vulgaris). They found a number of known anti-cancer compounds, including gallic acid, chlorogenic acid, epicatechin, myricetin, formononetin, caffeic acid, and kaempferol.
They also found the bean extracts inhibited the growth of human colorectal cancer and human breast cancer cells.
In a 2013 study from the Complutense University of Madrid, raw, cooked and germinated black beans (Phaseolus vulgaris) all had anti-tumor effects, particularly with colorectal and breast cancer as well as melanoma cancer cells. The raw beans had the most anti-tumor effects in this research.
Black bean sprouts also inhibit cancer cells
This doesn’t mean that sprouted beans don’t also inhibit cancer. In fact, they may well have a greater effect due to their increased assimilation.
In a 2013 study, researchers from Mexico’s Monterrey Institute of Technology determined that black bean sprouts are anticarcinogenic against breast cancer, liver cancer and colon cancer cells.
The researchers sprouted black beans (Phaseolus vulgaris) and then tested them and their constituents against cancer cell lines of various types of cancers. The researchers found that after three days and five days of germination, the phytonutrient extracts isolated from the sprouts were able to inhibit the growth of all the cancer cells tested.
They also tested the same sprout isolates against non-cancerous (healthy) cells as controls and found no negative impact upon healthy cells. (Many of the above studies also did this as well.)
The researchers then isolated some of the constituents of the sprouted beans and found that the saponins and flavonoids had the greatest inhibition against liver and colon cancer cells. Meanwhile, the genistein content of the sprouts was found to inhibit the breast cancer cells.
The researchers also found the black bean sprouts to be particularly high in antioxidants.
What about phytates?
Early sprout research as documented by Hofsten (1979) and others determined that sprout germination increases many nutrients and others are made more available for assimilation.
Other research (Chen and Pan 1977) found that germination decreased phytic acid in soybeans by 22% while the enzyme phytase increased 227% after five days of soybean germination.
Cooking beans also decreases their phytic acid content and increases their phytase content.
Because phytic acid/phytate can bind some minerals, eating raw beans is not advised. Nutrients like calcium and zinc are more assimilable from sprouted or cooked beans.
Also, the oligosaccharides that produce flatulence are hydrolyzed during sprout germination and to a lesser degree by cooking, making bean sprouts and well-cooked beans easier to digest.
Beans are particularly high in a number of phytonutrients, including flavonols like quercetin and kaempferol, and anthocyanins. They are also high in polyphenols like ferulic acid and chlorogenic acid. All of these are potent antioxidants shown to stimulate the immune system.
Kumar S, Sharma VK, Yadav S, Dey S. Antiproliferative and apoptotic effects of black turtle bean extracts on human breast cancer cell line through extrinsic and intrinsic pathway. Chem Cent J. 2017 Jun 20;11(1):56. doi: 10.1186/s13065-017-0281-5.
Papandreou C, Becerra-Tomás N, Bulló M, Martínez-González MÁ, Corella D, Estruch R, Ros E, Arós F, Schroder H, Fitó M, Serra-Majem L, Lapetra J, Fiol M, Ruiz-Canela M, Sorli JV, Salas-Salvadó J. Legume consumption and risk of all-cause, cardiovascular, and cancer mortality in the PREDIMED study. Clin Nutr. 2018 Jan 9. pii: S0261-5614(17)31439-5. doi: 10.1016/j.clnu.2017.12.019.
Une S, Nonaka K, Akiyama J. Lectin Isolated from Japanese Red Sword Beans (Canavalia gladiata) as a Potential Cancer Chemopreventive Agent. J Food Sci. 2018 Feb 13. doi: 10.1111/1750-3841.14057.
Joghatai M, Barari L, Mousavie Anijdan SH, Elmi MM. The Evaluation of Radio-sensitivity of Mung Bean Proteins Aqueous Extract on MCF-7, Hela and Fibroblast Cell Line. Int J Radiat Biol. 2018 Feb 26:1-29. doi: 10.1080/09553002.2018.1446226.
Chan YS, Xia L, Ng TB. White kidney bean lectin exerts anti-proliferative and apoptotic effects on cancer cells. Int J Biol Macromol. 2016 Apr;85:335-45. doi: 10.1016/j.ijbiomac.2015.12.094.
Luna Vital DA, González de Mejía E, Dia VP, Loarca-Piña G. Peptides in common bean fractions inhibit human colorectal cancer cells. Food Chem. 2014 Aug 15;157:347-55. doi: 10.1016/j.foodchem.2014.02.050.
Ombra MN, d’Acierno A, Nazzaro F, Riccardi R, Spigno P, Zaccardelli M, Pane C, Maione M, Fratianni F. Phenolic Composition and Antioxidant and Antiproliferative Activities of the Extracts of Twelve Common Bean (Phaseolus vulgaris L.) Endemic Ecotypes of Southern Italy before and after Cooking. Oxid Med Cell Longev. 2016;2016:1398298. doi: 10.1155/2016/1398298.
Borresen EC, Brown DG, Harbison G, Taylor L, Fairbanks A, O’Malia J, Bazan M, Rao S, Bailey SM, Wdowik M, Weir TL, Brown RJ, Ryan EP. A Randomized Controlled Trial to Increase Navy Bean or Rice Bran Consumption in Colorectal Cancer Survivors. Nutr Cancer. 2016 Nov-Dec;68(8):1269-1280.
Guajardo-Flores D, Serna-Saldívar SO, Gutiérrez-Uribe JA. Evaluation of the antioxidant and antiproliferative activities of extracted saponins and flavonols from germinated black beans (Phaseolus vulgaris L.). Food Chem. 2013 Nov 15;141(2):1497-503.
López A, El-Naggar T, Dueñas M, Ortega T, Estrella I, Hernández T, Gómez-Serranillos MP, Palomino OM, Carretero ME. Effect of cooking and germination on phenolic composition and biological properties of dark beans (Phaseolus vulgaris L.). Food Chem. 2013 May 1;138(1):547-55.
Ranilla LG, Genovese MI, Lajolo FM. Polyphenols and antioxidant capacity of seed coat and cotyledon from Brazilian and Peruvian bean cultivars (Phaseolus vulgaris L.). J Agric Food Chem. 2007 Jan 10;55(1):90-8.
Case Adams is a California Naturopath and a Board Certified Alternative Medicine Practitioner with a PhD in Natural Health Sciences. He has authored 26 books on natural healing strategies. “My journey into writing about alternative medicine began about 9:30 one evening after I finished with a patient at the clinic I practiced at over a decade ago. I had just spent the last two hours explaining how diet, sleep and other lifestyle choices create health problems and how changes in these, along with certain herbal medicines and other natural strategies can radically yet safely turn our health around. As I drove home that night, I realized this knowledge should be available to more people. So I began writing about health with a mission to reach those who desperately need this information. The strategies in my books and articles are backed by scientific evidence along with wisdom handed down through traditional medicines for thousands of years.”