Here in the sunny southwest with its large Mexican-American population the pinto bean is found in stores everywhere as it is a staple in their traditional diet. The pinto bean should be part of your diet too as most Americans struggle to obtain the minimum daily requirement of fiber, which is 38 grams per day for men, and 25 grams per day for women. Pinto beans go a long way to fulfill that need as one cup of cooked beans supplies 15 grams, or 60% of the amount needed for women, and about 40% needed for men.
And, as almost everyone is concerned with getting enough protein, note that beans are unique in that they are high in both fiber and protein as one cup of cooked pinto beans also supplies 15 grams of protein.
One cup of cooked beans also contains 294 mg of Folate, which is necessary to enhance the body’s metabolism and promote cellular growth. This is more than the amount of folate found in 3 cups of raw spinach (175mg) or two cups of cooked Brussel sprouts (187mg). This much folate supplies 74% of the MDR.
For those who do not wish to take fish oil, beans are also a good source of omega-3 fatty acids, as one cup contains 234 mg. This is more Omega-3 than is found in a four ounce serving of Cod or Tilapia. Omega-3 fats have been shown to reduce inflammation and are believed to help protect your coronary arteries from atherosclerosis.
One cup of cooked pinto beans also supplies the following nutrients:
- Magnesium, (85 mg) 21% MDR
- Potassium, (746 mg) 21% MDR
- Iron (3.6 mg) 20% MDR
- Thiamine (0.3 mg) 22% MDR
- Calcium (78 mg) 8% MDR
- Vitamin E (alpha tocopherol) (1.6 mg) 8% MDR
- Zinc (1.7 mg) 11% MDR (1)
But beans are not just about vitamins and minerals as the most compelling reason to eat pinto beans, or any bean for that matter, can be traced to an exciting finding first published in the Asia Pacific Journal of Clinical Nutrition, entitled, “Legumes: the most important dietary predictor of survival in older people of different ethnicities.”
This study followed 785 people age 70 and over in five cohorts in Japan, Sweden, Greece and Australia for up to seven years. The five cohorts were divided into Japanese in Japan, Swedes in Sweden, Anglo-Celts in Australia, Greeks in Australia, and Greeks in Greece. The type of beans consumed by the five cohorts varied by country and ethnicity. The Japanese ate primarily soy, tofu, natto (fermented soybeans) and miso (fermented soybeans usually consumed as a soup or stir fry). The Swedes ate brown beans and peas. The Greeks ate lentils, chickpeas and white beans. The Anglo-Celts in Australia, who had the lowest mean consumption of legumes of only 14 grams per day, ate mostly baked beans and peanut butter. But regardless of what type of bean was consumed, only for legume intake were the results consistently statistically significant. There was a 7 to 8 percent reduction in mortality for every 20 gram (approximately two tablespoons) per day increase in legume intake with or without adjustment for either location or ethnicity. (2) Greek Australians had both the lowest mortality after five years and the highest mean intake of legumes of 86 grams per day. (3)
And this is not the only study that found a connection between legume consumption and longevity. A much larger study, the Japan Collaborative Cohort Study, which followed 60,000 adults for thirteen years, found that the highest bean intake (4.5 servings a week) was associated with a 10% reduction in total mortality. (4)
So what is it about beans, are they, like the beans in the fable, “Jack and the Beanstalk”, truly magical? Although we know that beans have been grown since antiquity and that they are the only cultivated plant that has the ability to fix nitrogen from the atmosphere through the specialized bacteria that live in the nodules on their roots, thus increasing their protein content, there is much we have yet to learn about the various phytonutrients that comprise the many varieties of legumes now consumed around the modern world.
We do know that the resistant starch, oligosaccharides (one of the components of fiber found in plants) and remaining fiber found in beans pass undigested through the stomach and small intestine to the colon where they provide “prebiotics” or an energy source for the existing “probiotic” or beneficial bacteria already living there. This bacterial fermentation leads to the formation of short chain fatty acids such as Butyrate which is thought to promote a healthier gut, thus reducing the risk of colon cancer. (5)
Legumes have also been found to not only reduce blood glucose levels immediately after they are eaten but also after a meal eaten later in the day, which helps reduce the risk of diabetes. This attribute, unique to beans and some whole grains, such as barley and rye kernels, is known as the second meal effect. (6)
Intervention trials have also shown that legumes can reduce cardiovascular disease risk factors such as cholesterol, triglycerides, blood pressure, blood sugar levels and enhance weight loss. (7) Clinical studies suggest that it is the saponins in legumes (name is derived from ability to create stable soaplike forms in aqueous solutions) that help protect against cancer, reduce cholesterol, and lower the blood glucose response. (8) Other studies report that the phytosterols (a plant sterol) found in beans and other plants also block the absorption of cholesterol from food. The European Foods Safety Authority (EFSA) concluded that blood cholesterol could be reduced in an average range from between 7 to 10.5% depending on the number of grams of plant sterols a person consumes per day.
Longer-term studies extending up to 85 weeks showed that the cholesterol-lowering effects of sterols could be sustained. The EFSA scientific panel was sufficiently impressed by the data to release the following health advisory: “Plant sterols have been shown to lower/reduce blood cholesterol. Blood cholesterol lowering may reduce the risk of coronary heart disease.” (9)
But perhaps we should clear the air, so to speak, about why most people are reluctant to include beans in their daily diet. This, of course, would be the fear of flatulence and the resultant potential embarrassment in social situations. A recent study showed that the bowel adjusts to the regular intake of legumes in just two weeks. In the first week half the participants in the study reported increased gas, but by the second week over 70% reported the increased gas had returned to baseline. (10)
So there are many reasons to include beans in your daily menu. Not only are they an excellent source of fiber and protein, but they are a cheap and healthy way to obtain significant amounts of folate, omega-3 fatty acids, as well as other essential vitamins and minerals. Due to space constraints we have not discussed all the reasons to eat beans and there are many, as they have been positively associated with almost everything from increased bone mineral density to slowing skin aging and wrinkling. But whether or not it is the resistant starch, oligosaccharides, saponins, phytosterols or some other “magical” component of legumes yet to be discovered it is clear that beans offer a myriad of protective benefits that can not only reduce cholesterol, blood pressure, cardio vascular disease risk, blood glucose levels, and cancer risk but significantly enhance longevity.
1. Nutritiondata.self.com; pinto beans/legumes/beans pinto/mature seeds, cooked, boiled without salt. Nutrition facts & calories, Accessed 7/3/16
2. Daramadi-Blackberry I, Wahlqvist, ML, Kouris-Blazos A, Steen B, Lukito, W, et al. Legumes: the most important dietary predictor of survival in older people of different ethnicities. Asia Pac J Clin Nutr. 2004; 13 (2): 217-20
3. Kouris-Blazos A, Belski R. Health Benefits of legumes and pulses with a focus on Australian Sweet Lupins. Asia Pac J Clin Nutr. 2016; 25 (1): 1-17
4. Nagura J, Iso H, Watanabe Y, Maruyama K, Date C, Totyoshima H, et al. Fruit, Vegetable and bean intake and mortality from cardiovascular disease among Japanese men and women: The JACC Study. Br J Nutr. 2007: 102:285-92. Doi 10.1017/50007114508143586
5. Bird AR, Conlan MA, Christopherson CT, Topping DL. Resistant starch, large bowel formation and a broader perspective of prebiotics and probiotics. Benef Microbes. 2010; 1:423-31, doi:10.3920/BM2010.0041
6. Mollard RC, Wong CL, Luhovy BL, Anderson, GH. First and second meal effects of pulses on blood glucose, appetite and food intake at a later meal. Applied Physiol Nutr Metab. 2011; 36:634-42. doi:10:1139/h11-071
7. Flight J, Clifton P. Cereal grains and legumes in the prevention of coronary heart disease and stroke: a review of the literature. Eur J Clin Nutr. 2006;60:1145-59
8. Shi J, Arunasalam K, Yeung D, Kakuda Y, Mittal G, et al. Saponins from edible legumes: chemistry, processing and health benefits. J Med Food 2004 Spring; 7 (1):67-68
9. European Food Safety Authority. Plant sterols and blood cholesterol – scientific substantiation of a health claim related to plant sterol and lower/reduced blood cholesterol and reduced risk of (coronary) heart disease pursuant to Article 14 of Regulation (EC) No 1924/2006
10. Winham DM, Hutchins AM. Perceptions of flatulence from bean consumption among adults in 3 feeding studies. Nutr J. 2011;10:128 doi: 10.1186/1475-2891- 10-128