New Evidence of the Benefits of Certain Foods
I’m not alone in promoting the benefits of a healthful diet. Certain foods get mentioned repeatedly, due to their especially healthful combination of nutrients. Among the top foods widely recommended by experts, salmon, eggs and nuts have been cited as excellent sources of complete protein, healthful fats and various vitamins and minerals. Now scientists have discovered that an amino acid in these foods has the ability to improve blood sugar control.
Type 2 diabetes, sometimes referred to as “diet-induced diabetes” is a condition in which the body does not produce enough insulin, or the body’s cells do not respond as they should to circulating insulin. In healthy people, insulin is released from the pancreas in response to rising blood sugar levels (glucose) after a meal. It signals cells to take up glucose for energy. This removes glucose from the bloodstream, returning blood sugar levels to normal.
When we eat, a hormone known as GLP-1 is released from the intestines in response to the presence of certain nutrients. GLP-1 helps control appetite, and triggers the release of insulin. It’s a target of certain drugs for diabetes. Boosting the activity of GLP-1 effectively improves blood sugar control, provided a patient is still capable of producing insulin.
Now a team of researchers from Denmark and the U.S. has shown that foods rich in the amino acid, l-arginine, help boost GLP-1 secretion, which in turn significantly improves blood sugar control after a meal, even among diabetics. By supplementing the diets of laboratory mice with l-arginine, investigators showed that it’s possible to improve glucose clearance by up to 40%, in lean and obese mice alike. That’s comparable to the action of certain existing diabetes drugs. Almonds and hazelnuts are especially rich sources of dietary l-arginine. Not surprisingly, nuts are on most experts’ lists of top superfoods.
Clemmensen C, Smajilovic S, Smith EP, Woods SC, Bräuner-Osborne H, Seeley RJ, et al. Oral L-arginine Stimulates GLP-1 Secretion to Improve Glucose Tolerance in Male Mice. Endocrinology. 2013 Aug 19. [Epub ahead of print]