(NaturalNews) Just a single serving of legumes a day can significantly improve cholesterol levels and lower your risk of cardiovascular disease, according to a study conducted by researchers from St. Michael's Hospital in Canada and published in the Canadian Medical Association Journal on April 7.
"Legumes are generally considered healthy, but there [are no guidelines] about their intake from public policy officials," lead author Dr. John Sievenpiper said.
Eat local, eat healthy
Legumes, also known as pulses, are a family of plants that includes beans, lentils and peas.
Researchers reviewed the results of 26 prior studies on the connection between legumes and heart health, including a total of 1,037 people. All of the studies were randomized, controlled trials. The researchers found that eating just one three-quarter-cup serving of legumes per day reduced LDL ("bad") cholesterol levels by 5 percent, which could lead to a 5 or 6 percent reduction in cardiovascular disease risk.
LDL levels decreased more in men than in women. Although the researchers could not explain this effect, they noted that, on average, men are known to have higher cholesterol levels and to eat poorer diets than women. They speculated that, because of these factors, men might respond more strongly to an improvement in their diets.
The researchers further noted that some participants did report objectionable effects to legume consumption, such as bloating, gas, constipation or diarrhea. These symptoms tended to reduce and disappear over time, however.
The studies were not designed to explain the beneficial effects of legumes, but the researchers noted that pulses often play the same role in a meal that would otherwise be played by animal protein, animal fat or trans fats. As such, pulses may be displacing less healthy foods as well as providing a benefit on their own.
"We have a lot of room in our diets for increasing our pulse intake to derive the cardiovascular benefits," Dr. Sievenpiper said.
"Pulses already play a role in many traditional cuisines, including Mediterranean and South Asian. As an added bonus, they're inexpensive. Since many pulses are grown in North America, it's also an opportunity to buy and eat locally and support our farmers."
Legumes for your health
Legumes are lauded by nutritionists for their high fiber content, low glycemic index and richness in protein, complex carbohydrates, iron, magnesium, phosphorus, zinc and other nutrients.
"It is a well-known fact that high-soluble, fiber-rich foods, like legumes, produce significant effects on LDL numbers and actually add to the cholesterol-lowering effects of statins," said Dr. Chip Lavie of Ochsner Heart and Vascular Institute in Louisiana.
"People should seriously think about adopting legumes in their diet. The LDL-lowering effect aside, it's a healthy thing to be doing, anyway."
Dr. Walter Willet of the Harvard School of Public Health said the study adds new evidence to the health benefits of legumes.
"[The study] appears to be a useful summary of the literature on metabolic effects of legume consumption and suggests that there are benefits, especially if beans or other legumes replace red meat," Dr. Willett said.
He also noted that legume cultivation produces significantly lower greenhouse gas emissions than livestock production, providing another benefit to replace some of the meat in your diet with legumes.
In addition to promoting general health and lowering LDL cholesterol, legumes have also been shown to lower blood pressure and reduce the risk of type 2 diabetes. However, legume consumption in the U.S. is very low overall. To eat the single three-quarter cup recommended by the study, the average U.S. consumer would need to more than double his or her legume consumption.