Beans May Improve Blood Glucose Control

Eating legumes such as beans, chickpeas, and lentils may help improve blood glucose control and reduce blood pressure, cholesterol, and triglyceride (blood fat) levels in people with Type 2 diabetes, according to a new study from researchers at the University of Toronto.


Foods that have a low glycemic index, or GI, (meaning that they produce a gradual rise in blood glucose levels) have been shown to improve blood glucose control in people with Type 2. To determine whether decreasing the overall GI of one’s diet by increasing the consumption of low-GI legumes would benefit blood glucose control and other health parameters, the researchers randomly assigned 121 people with Type 2 diabetes to one of two diets for three months: a low-GI diet that required participants to eat at least one cup of legumes per day, or a diet that increased insoluble fiber through the consumption of whole wheat products.

At the end of the three-month period, the investigators found that the average A1C levels of people who had increased their legume consumption had dropped from 7.4% to 6.9%, compared to an average drop from 7.2% to 6.9% for those eating increased amounts of whole wheat.

The legume diet also reduced cardiovascular risk considerably more than the whole wheat diet, owing mainly to a decrease in blood pressure: Compared to no blood pressure change on the whole wheat diet, on the legume diet, systolic pressure (the top number) dropped from an average of 122 to 118 points and diastolic pressure (the bottom number) dropped from an average of 72 to 69, corresponding to a roughly 1% decrease in the 10-year risk of heart attack or stroke.

Furthermore, the legume diet significantly lowered average total cholesterol and triglyceride levels

In an accompanying editorial, Marion Franz, MS, RD, questioned whether people with diabetes would be able to eat the amount of legumes necessary to improve blood glucose control. But according to lead study author David Jenkins, MD, PhD, in an interview with Fox News, “The public should be doing some preventive strategies using these foods. We are not introducing some novel ‘Frankenfood’ into the diet — this is really deep, traditional stuff.”

To learn more about the research, read the article “Legumes May Aid Glycemic Control, Cut Lipids” or see the study’s abstract in the Archives of Internal Medicine.

And when you’re finished with that, be sure to check out some of our delicious bean- and legume-based recipes, such as our black bean and vegetable enchiladas, sweet and sour five-bean bake, and upside-down taco.

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  • Deb

    Wow, a really good reason to eat those beans! A cup a day is not at all hard to do, Marion Franz notwithstanding. Lentils are a particularly good legume because it only takes 30 minutes to cook them from the dried form, and Westbrae organic has a delicious canned lentil product. We’ve been eating lentil soup for years just because it’s so good. My A1c was terrific when I was eating whole wheat crackers with hummus every evening in addition to following a Mediterranean diet, which also emphasizes legumes. Beans and rice are a traditional combination in most parts of the world, including New Orleans where red beans and rice are a Monday night staple. The variety of canned beans available now makes it really easy to enjoy them every day.

  • Paul Veverka

    I have been an insulin dependent diabetic for 39 years. I have asked this question of all of my many doctors I have had over the years.No matter what my blood sugar number is when I arise in the A.M. from 65 to 250 whenever I eat eggs within 2.0 hours I will encounter a severe low,with blood test numbers at around40. Why do eggs cause this . If I eat a muffin,toast, fruit, cereal. It will never fall like this?
    I have told I am a brittle diabetic no matter how I try and my Dr.advise I am always around 200 blood sugar.8.5 A1C. my current Dr says that may be your normal. Its been this way for at least 15 years. Could this be a normal for me?

    Thank You
    Paul Veverka

  • Pat Weiser

    I like beans and try to incorporate them, but only on days or nights I don’t have to do anything else. The gas! The gas! It’s horrible, and since I had gastric bypass surgery (which did NOT put my diabetes in remission) it’s even worse. I have tried Beano, I have tried chewing them to a pulp, and nothing seems to help. Any ideas?

  • Deb

    Pat, if you soak and cook the beans yourself, you can eliminate about half of the substances causing the gas. The trick is to soak the beans overnight in cold water, then discard the soaking water and use fresh water to cook them. This also helps them cook faster and better.
    Have you tried lentils? They don’t require presoaking, but they are also available canned. They don’t seem to produce gas like the other legumes, but to be extra cautious you could soak the dried ones before cooking. They are very versatile. When I was on a vegan diet, I even had them on spaghetti in place of ground beef.
    I hope you find a way to enjoy them without gas. I’m sorry the bypass didn’t put you in remission!

  • Cheryl

    I use to make a dish with 1/2 cup, black beans, 1/2 cup brown rice, 1/8 of avocado, 1/4 cup salsa, and 3 oz chicken or fish or steak…I loved it and did not seem to make me too gassy if at all. I have fallen off my good nutrition due to being introduced to a CPAP having been diagnosed as having sleep apnea! I have gained back 25 pounds in 6 months after taking off 50 in a month an half…I do not exercise like I was and eat the way my dietitian taught me to. I am trying to start back the way I was, it is taking a lot of mental strain to do, but I know I have to. Hope the recipe is enjoyed, I loved it. I would put together a good salad too and a serving of a fruit to finish the meal. ūüėČ

  • gloria

    You should be able to eat all the beans you want with no side effects if you will take enzymes with probiotics.