This is the sixth column about Dr. Michael Greger’s Daily Dozen, foods he recommends eating every day for optimal health. His favorite legumes are black beans, black soybeans, black-eyed peas, butter beans, cannellini beans, garbanzo beans, also known as chickpeas, edamame, English peas, great northern beans, kidney beans, lentils, miso, navy beans, pinto beans, small red beans, split peas and tempeh.

A few years ago, the Post Independent did a series on aging in the Roaring Fork Valley, with the final highlight being a presentation about the Blue Zones, five places in the world where people live particularly long and healthy lives. Common threads among these otherwise disparate populations are frequent low-level physical activity, a plant-predominant diet and, most notably, daily legume consumption.

Dr. Greger recommends three servings of legumes a day. A serving size is one-fourth cup of hummus or bean dip; one-half cup of cooked beans, split peas or lentils; one-third cup of tofu or tempeh; or 1 cup of fresh peas or sprouted lentils. Raw beans are toxic, so be sure to cook them, which only takes about 30 minutes in a pressure cooker. Canned beans are precooked, but be sure the label says no added salt. One good brand is Eden, available at Natural Grocers.

Health benefits legumes provide include the following:

All plants have protein, but legumes have the most. A cup can contain up to 30 grams.

Legumes contain iron, zinc, folate and potassium.

Fiber feeds the health-promoting bacteria in our gut microbiome. Fiber is found only in plants, and legumes have the most of any plant. A cup of legumes can contain about half of the daily recommended intake of fiber.

Legumes have phytates and other cancer-fighting nutrients. The most comprehensive analysis of diet and cancer ever performed was published in 2007 by the American Institute for Cancer Research. Its recommendation was to eat whole grains and/or legumes with every meal, three times a day.

They lower cholesterol.

When legumes pass down to the colon and the gut bacteria start feasting on them, chemicals are produced that cause a feeling of fullness for hours afterward, a phenomenon called “the second meal effect.” This results in better blood sugar control in people with diabetes and weight loss in people who are overweight.

Legumes help with loss of belly fat, the type of fat that leads to prediabetes, type 2 diabetes and cardiovascular disease.

When patients are advised to increase their legume intake, they often express concern about unpleasant gas. It is wise to increase intake of legumes gradually, but once people are on a consistent daily high-legume intake, the gas problem usually resolves. Edamame, or soybeans, and soy products such as tofu are almost always well-tolerated, as are lentils.

Here is what Kaiser Permanente recommends to cut down on gas in its pamphlet, “The Plant-Based Diet, a Healthier Way to Eat”: Put beans in a large pot and cover with 2 inches of water; bring to a boil for three minutes; cover and set aside for one to four hours; rinse and drain well; then cook. Note that raw beans can be toxic.

When talking about unpleasant gas, it is worth noting that the rotten egg smell of flatus and stool is from hydrogen sulfide, which is associated with an animal-based, but not a plant-based, diet.

In summary, eat lots of legumes daily. Add them to salads, stir-fry dishes and soups, or try making three-bean chili. You can even eat them for dessert in the form of Dr. Greger’s black-bean brownies. The recipe is in his “How Not to Die Cookbook,” or at nutritionfacts.org/recipe/fudgy-no-bake-brownies.

Soy warrants a column of its own, which will be next week.

Dr. Greg Feinsinger is a retired family physician with a special interest in prevention, treatment, and reversal of chronic disease through nutrition. He is available for free nutritional counseling and shop-with-a-doc grocery store tours. He can be contacted at 970-379-5718 or gfmd41@gmail.com.