Beans Fight Diabetes:

Beans Seen to Discourage Weight Gain and Diabetes

Part 1

by Craig Weatherby
Courtesy of Vital Choice Seafood

Ever since Dr. Atkins took up his cudgel against dietary carbohydrates (sugars and starches), people have tended to perceive this major food group as fattening fare.

To be sure, Atkins was right about the potent glycemic (blood-sugar-raising) effects of sugars and the rapidly absorbed starches in refined flour products like pastries, white bread, and pasta.

But there are important distinctions between starchy foods: ignorance of which leads many to shun high-starch foods that do no harm and can even help control weight and discourage diabetes.

Regular vs. “resistant” starch: the basics

Dietary carbohydrates consist of simple carbohydrates, or sugars, and complex carbohydrates, or starches.

Starches are chains of sugar molecules, whose individual conformations make them distinctly different with regard to digestion, absorption, and blood-sugar control.

Most starches are digested and absorbed into the body in the small intestine.

But some starches resist digestion and pass through to the large intestine where they behave like dietary fibers: the even longer and less digestible chains of sugar molecules from which plants build their physical structures.

Nutrition scientists named these special kinds of carbs "resistant starch."

Legumes (beans, lentils, split peas, string beans) and whole, unprocessed grains contain the highest percentages of resistant starch. See table, below, for the resistant starch content of common beans and grains.)

Resistant starch limits the sharp spikes in insulin and glucose levels that normally follow consumption of foods high in easily digestible starches (sugars, fruit juice, soda, white bread, potatoes, and pastries) … even when the source of resistant starch is consumed many hours beforehand.

Research indicates that resistant starches can really help control people’s weight and reduce their risks of cardiovascular disease and diabetes:

Weight Control:

  • People who eat resistant starches increase fat-burning (thermogenesis) in their bodies. The authors of an Australian study found that when participants enjoyed a meal in which only 5.4 percent of its starch was the resistant kind, the rate at which their bodies burned (oxidized) body fat increased by 23 percent for a full day afterwards. Adding more resistant starch did not increase the rate of fat burning or its duration. It seems that a little goes a long way in this regard.
  • Rodents given resistant starches along with digestible starches maintain smaller fat cells (adipocytes) than companions fed only foods high in digestible starches.
  • Diabetes: When present in carbohydrate foods, resistant starch beneficially lowers the “glycemic response” to foods by releasing glucose into the bloodstream at a low, slow, steady rate.

People and animals who consume foods high in resistant starches along with foods high in regular starches maintain higher (i.e., healthier) levels of insulin sensitivity, compared with people and rodents who consume only foods high in regular starches.

  • Heart Health: Compared with people who consume only regular, digestible starches, people who also consume foods high in resistant starches enjoy lower cholesterol and triglyceride levels.
  • Cancer: When resistant starch reaches the colon, bacteria feed on it, just as they do on dietary fiber, producing a short-chained fatty acid called butyrate that’s known for its ability to curb the risk of colon cancers.
  • Resistant starches: Any repast’s healthful pièce de résistance

Pièce de résistance means the best part, highlight, or feature of something, such as a meal.

Beans, whole grains, and other foods rich in resistant starch meet the definition, as they add a healthful highlight to any a meal. In fact they make the perfect anti-aging complement to colorful, antioxidant-rich fruits and vegetables and to oily, omega-3-rich fish such as wild salmon.

The richest food sources of resistant starch--beans, lentils and other legumes--are also high in protein, fiber, and antioxidants.

Beans top the resistance charts

What starchy food satisfies energy and protein needs, delivers anti-inflammatory, antioxidant polyphenols, burns body fat, and moderates blood levels of both blood sugar and insulin?

The answer is “legumes”: that is, beans, lentils, and string beans. Beans contain the highest percentages of resistant starch, followed, at some distance, by whole, unrefined grains.

Prized by traditional cultures--and contemporary fans of ethnic cuisines--beans also serve double-duty as ace weight control allies.

The high levels of resistant starch in beans and whole grains could explain why, in population studies, people who get more of their protein from these complementary plant foods than from meats enjoy healthier body mass indices (height-weight ratios).

A meal featuring legumes raises blood sugar very slowly and moderately, and even moderates the blood-sugar (i.e., glycemic) response to relatively high-glycemic foods (sugars, refined flour products) consumed in the same or next meal you eat.

Aside from resistant starches, beans owe some of their weight-control and anti-diabetes benefits to three other factors:

Fiber: The non-digestible starches we call fiber—in which beans are especially rich—are satiating and stabilize blood sugar: two key factors in weight-control.

Many studies show that higher fiber intake is associated with lower body weight, body fat, and body mass index (weight-to-height ratio). Results from clinical trials are more mixed, although in most cases, higher fiber intake cuts peoples’ food consumption and drops their body weight.

Starch blockers (amylase inhibitors): Beans contain compounds called amylase inhibitors, which block the action of the enzyme (amylase) needed to digest starches. Hypothetically, this effect should help prevent digestion of some of the starch in beans themselves, and of the starch in other foods eaten with beans.

It is not clear exactly how effective the amylase inhibitors in whole beans are compared with taking purified phaseamolin: a supplemental amylase inhibitor extracted from white kidney beans.

Antioxidant pigments: Most of the pigments that color beans are anthocyanins: the same kinds of antioxidant polyphenol pigments that color berries. Anthocyanins help control blood sugar modestly and blunt the inflammatory--hence, pro-diabetic, blood-thickening, and artery-damaging--impact of dietary sugars and standard starches.

Please click here for part 2 of this article.

Editor's note: We consider organic whole foods from both plant and animal kingdoms to be a major key to superior health. We also think it's terribly important to eat fish at least twice a week to get the essential fatty acids. Here at our house, we only eat wild Alaskan salmon and other wild seafoods from our friends at Vital Choice. Click here to visit Vital Choice Seafood.


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