Can beans help lower my cholesterol levels?

All beans and legumes, without question, can be heart-healthy parts of a balanced diet and helpful in lowering cholesterol levels. There are several aspects of this beans-and-cholesterol equation, however, that may have been misunderstood amidst all of the popular press writing about diet, heart health, and cholesterol.

One of those potential areas of misunderstanding involves amount. How many beans does it take to reduce cholesterol? And how great a reduction in cholesterol levels can you expect from eating beans? Research in this area is clear and consistent: you can expect to get a 5-15% reduction in your LDL-cholesterol level when you change your diet to include about 1.5 cups of cooked legumes 4 days per week or more over the course of several months. This same level of bean intake can also be expected to lower your risk of coronary heart disease, on average, by between 10-20%.

While there are many benefits from eating beans, their exact role in your overall health will depend upon your other risk factors (both dietary and lifestyle) and your existing cholesterol levels. The American Heart Association describes an LDL-cholesterol level of 130-159 milligrams per deciliter as "borderline high," levels of 160-189 as "high," and levels above 190 as "very high." Even though a 5-15% decrease in your LDL level would be desirable if your LDL cholesterol was in the very high range, it would not drop your LDL level below the "high range" under any circumstance.

A second area of potential misunderstanding involves nutritional factors in beans and legumes that are actually responsible for cholesterol reduction. Original studies in this area focused heavily on the soluble fiber content of beans as the primary reason for cholesterol reduction. Beans are definitely very good sources of dietary fiber, including water-soluble fibers like pectins, gums, and mucilages. However, these fibers are not the only mechanism-and may not even be the primary mechanism-through which beans help reduce LDL cholesterol levels. Proteins, isoflavones, saponins, and other phytonutrients are all under active investigation as bean components that may play key roles in cholesterol reduction and protection against heart disease.

George Mateljan