Naveed Saleh, MD, MS, for MDLinx | May 07, 2020
Beans! Beans! They’re good for your heart. The more you eat, the more... healthy you are? Seems likely, according to the research. Beans are only one type of legume, though. Others include chickpeas, lentils, and peas. And they’re all good for you. They can lower cholesterol and blood pressure as well as help control weight and diabetes.
(Oh, an article about beans and peas? Who cares?) Wait, wait! Don’t stop reading there. There’s probably a lot more you don’t know about the puny but powerful legume. Or, are you a misolegumist—a hater of beans, lentils, and all things legume-y?
Well, join the crowd. Despite increased recognition that legumes are super healthy, the majority of Americans avoid them. On any given day, only about 8% of American adults eat legumes.
According to a recently published study in Nutrients, legume intake is on the decline among US adults, with consumption falling (mature legumes: 12.8% in 2011 to 8.3% in 2014; dry beans: 10.0% in 2011 to 6.5% in 2014). In addition, results of the 2017 Beans, Lentils, Peas Survey showed that fewer than 5% of participants ate legumes daily, and about one-third of people ate no legumes in the prior month.
That’s a shame because legumes are a nearly perfect food. They’re chock full of protein, fiber, carbohydrate, iron, copper, magnesium, B vitamins, zinc, manganese, and phosphorus. They’re also low in fat, with negligible amounts of saturated fats, and are devoid of cholesterol.
Legumes are major components of the Mediterranean diet, Dietary Approaches to Stop Hypertension (DASH) diet, vegan/vegetarian diets, and lower-glycemic-index diets.
There are two kinds of legumes: immature legumes (eg, peas, green beans, fresh lima beans, and edamame) which are eaten when they’re fresh, and mature legumes, which are picked from the pod when they’re fully grown and dried (eg, black beans, split peas, lentils, and chickpeas).
A review article published in Clinical Diabetes detailed the specific benefits of legumes with respect to various health conditions.
Hyperlipidemia. More than 12% of US adults are reported to have total cholesterol levels exceeding 240 mg/dL, according to the CDC. In addition, one third of the adult population reports not having had their cholesterol checked in the past 5 years.
Eating legumes often can help decrease cholesterol. In one meta-analysis of 10 randomized controlled trials, non-soybean legumes eaten for at least 3 weeks were shown to reduce total cholesterol and LDL levels. In addition, a low-powered clinical trial in patients with type 2 diabetes compared two diets for heart disease, one that substituted legumes for two servings of red meat 3 days/week and the same diet with no legumes. Researchers found that the legume-added diet improved levels of triglycerides and LDL cholesterol as well as fasting blood glucose and insulin levels.
Weight management. The CDC reports that approximately half of the US population suffers from obesity, with the highest rates observed among middle aged adults between the ages of 40 and 59.
Eating legumes may help control weight. Legumes are filling because of their protein, fiber, and slow-to-digest carbohydrate content. Another study of large-population data indicated that adults who ate a variety of legumes had lower body weights compared with those who abstained. Legume consumption was also associated with lower rates of obesity than non-consumption.
Hypertension. About half the US population is living with hypertension, with more men suffering from the chronic condition than women. Moreover, the CDC reports that “nearly half a million deaths in the United States included hypertension as a primary or contributing cause.”
The magnesium, potassium, and fiber content in legumes is linked to better blood-pressure control. A systematic review and meta-analysis found that in more than 500 people—half of whom were overweight/obese—those who ate legumes experienced decreases in blood pressure. Furthermore, those who ate nearly 1 cup of legumes each day for 10 weeks experienced decreases in systolic and mean arterial blood pressures.
Type 2 diabetes. The number of adults living with diabetes in the United States has exceeded 34 million, with type 2 diabetes—usually developed in middle age—making 90-95% of that number.
Diets high in legumes and low in sugar-sweetened beverages, refined grains, and processed meats lower the risk of developing diabetes, as well as improving lipid and blood-sugar control. Various studies have shown that legumes dropped hemoglobin A1C and blood glucose levels.
Legumes get a bad rap because people often assume that they take a lot of time and trouble to prepare. Or that they require long overnight soaking periods and always turn out mushy. Not true! There are several “low maintenance” legumes out there, with a plethora of different preparation options, including salads, soups, and casseroles. At the end of the day, the health benefits of legumes are far too great to be wasted.