Why You Should Love Legumes

Tamara Duker Freuman

If you read the Cliffs Notes version of any purportedly anti-inflammatory elimination diet protocol currently enjoying its 15 minutes of fame, you'll notice a common set of dietary demons. From Paleo and Whole30 to the more niche regimens like AIP (that's Autoimmune Paleo) and the lectin-bashing "Plant Paradox" diet, included among the no-no list of ill-reputed foods and ingredients like refined sugars, refined carbs and artificial food additives is a family of foods that puzzles me: legumes.

Yet there are many reasons to love legumes:

-- Good source of plant-based protein.

-- Associated with health and longevity.

-- Actively anti-inflammatory.

-- An excellent source of fiber.

-- An excellent source of isoflavones and phytonutrients.

Legumes refer to plants in the botanical family Fabaceae. These plants -- which produce foods as varied as lentils, chickpeas and soybeans to peanuts, peas, alfalfa and tamarind -- have a property that makes them essential to sustainable agriculture. They capture nitrogen gas from the air and return it into the soil, enriching the soil and alleviating the need to add fossil-fuel-based fertilizers. (To be fair, this so-called "nitrogen fixing" service is carried out by symbiotic bacteria that attach themselves to the roots.) This agricultural party trick means that nitrogen -- an essential component of protein -- is available for the plant's fruits or seeds. This is why legumes are such a good source of plant-based protein.

[See: High-Protein Breakfast Ideas.]

According to Elizabeth Berry's "Great Bean Book," the archaeological record suggests that human beings have been eating legumes for over 10,000 years. They're mentioned in the Old Testament. If you're familiar with the book of Genesis, you'll recall that Esau sold his birthright for a steaming bowl of lentil soup. Though if your religious education is limited to reading the package label of the cultishly popular Ezekiel 4:9 bread, you'd still know that Ezekiel the prophet was blathering on about making bread from beans about 2,600 years ago.

Legume Intake: The Single Strongest Predictor of Longevity

People who live in the world's nine so-called "Blue Zones," or regions known for their exceptional health and longevity, have literally only one dietary factor in common: they all include some sort of beans (legumes) in their daily diets. In Okinawa, it's more likely to be be soybeans; in Costa Rica, it's more likely to be black beans. And in Sardinia, it may often be chickpeas. Eating lots of beans is the common thread among people who live the longest, healthiest lives.

Large, well-designed research studies have validated the importance of legumes to modern human health, showing strong evidence for a longevity-promoting benefit associated with regular intake of legumes. One study of the oldest people in multiple different developed countries -- including Japan, Sweden, Australia and Greece -- found that legume intake was the single strongest predictor of survival, with an 8% reduced risk of death associated with each additional 20g of legumes consumed per day. In a cohort of 4,000 Costa Rican men followed for a 10 year period -- half of whom had suffered a heart attack previously and half of whom had not -- researchers observed that consuming one serving of beans per day was associated with a 38% reduced risk of heart attack compared to eating beans less than once per month. (Remember the childhood ditty: "Beans, beans, good for your heart..."?) Another study including over 10,000 people with Type 2 diabetes in Europe found that higher intake of legumes was associated with reduced risk of death over the nine year study period.

[See: 7 Reasons to Choose a Plant-Based Diet. ]

These studies are just the tip of the iceberg of a large and robust body of evidence that all points to the same conclusion: Regular intake of legumes is foundational to a variety of different longevity-promoting human diets. How on earth, then, do fad diet creators get away with slapping an "inflammatory" label on them -- lumping them together in the same category as sugar and white flour?

This maligning of legumes is madness. It's time for the common-sense-loving hordes to rise up in defense of these essential, economical sources of plant-based proteins, these fixers of nitrogen and bearers of life-prolonging, anti-inflammatory nutrients.

You heard me right. Not only are legumes NOT inflammatory, they're actively anti-inflammatory. The Dietary Inflammatory Index -- an evidence-based tool developed by researchers who reviewed over 1,900 research studies investigating the effect of certain foods or food components on six markers of systemic inflammation in the body -- assigns a "pro" or "anti" inflammatory score to dozens of foods and nutrients or compounds they contain.

[See: 9 Most Common Food Allergies.]

Legumes Are Anti-Inflammatory

Beans and the rest of the legume family are an excellent source of several of the more anti-inflammatory nutrients and compounds on the DII, including:

-- Fiber: Beans, peas, lentils, chickpeas and peanuts are all very high in fiber, which likely exerts its strong anti-inflammatory effect at least in part by nourishing our gut microbiota so well. Depending on the variety, ½ cup serving of cooked beans contains between four and nine grams of fiber.

-- Isoflavones: These plant-based compounds, sometimes referred to as phytoestrogens, are the exclusive domain of legumes, like soybeans, cowpeas and mung bean sprouts. Contrary to their undeservedly bad reputation, it's thought that they may be protective against hormone-driven cancers, possibly by taking the place of more bioactive human estrogen on cell receptors.

-- Flavonoids: This large family of phytonutrients are what give many fruits and vegetables their bold colors and have powerful antioxidant effects. The skins of black beans, red kidney beans and a variety of brown beans are particularly concentrated sources of them.

-- Anthocyanins: These are a subtype of flavonoid responsible for the red, blue and purple colors of nutrient-dense fruits and veggies. Black beans contain very high levels of them.

Look, if beans make you feel too gassy and bloated, if you're allergic to peanuts or if you simply don't like how some of these foods taste, then by all means, don't eat them. But if you like beans, lentils and chickpeas -- and you're going out of your way to avoid one of the few food families that can legitimately claim to be a super food under the misguided notion that legumes are somehow bad for you -- know that legume-bashing diets are simply... wait for it... full of beans.