Rethinking the Type 2 Diabetes Diet

Incidence of type 2 diabetes in the United States has doubled in the past three decades. Currently, about 17 million Americans have the disease. Type 2 diabetes is growing to epidemic proportions, and its related to the growth in obesity, says Hope Warshaw, R.D., author of Diabetes Meal Planning Made Easy (American Diabetes Association, 2006). Some 80% of type 2 diabetics are overweight.

In type 2 diabetes, muscle, liver and fat cells do not utilize insulin properly. Eventually, the pancreas cant make enough insulin for the bodys needs, and blood glucose levels rise, leading to complications like nerve and blood-vessel damage, heart disease, stroke, blindness, kidney disease, gum infections, and amputation. Cardiovascular disease (CVD) is a serious risk associated with diabetes; among diabetics aged 35 years and older, 38.1% have reported a CVD condition.

An additional 41 million people are at high risk for diabetes. Due to conditions like prediabetes (higher than normal blood sugar, but not classified as type 2 diabetes), insulin resistance (body cells do not respond appropriately to insulin), and metabolic syndrome (a group of risk factors for type 2 diabetes), the American Diabetes Association (ADA), Alexandria, VA, is shining the spotlight on prevention through diet and weight loss.

New era for diets 

The old nutrition and diabetes philosophy of banning simple sugars in lieu of starches was based on the notion that sugars were more rapidly digested and absorbed than starches. However, sucrose produces a glycemic response similar to high-starch, refined carbohydrates. Its not about low carbs, its about the quality of the carbs, says Warshaw. Todays carb focus is on nonstarchy vegetables and fruits, whole grains over processed grains, dried beans, water and calorie-free beverages instead of sweetened drinks, fewer high-calorie snack foods and desserts, and moderate portion sizes. The ultimate diet goal is to help improve cardiovascular heath, reduce body fat, keep blood pressure in normal range, and increase sensitivity to insulin, which decreases the risk for developing complications. Several tools can be helpful for meal planning, including the Diabetic Food Guide Pyramid, Rate Your Plate, Making the Exchange, and Carb Counting.

In Sept. 2006, Diabetes Care (29:2140-2157) published ADAs current position statement on nutrition recommendations for diabetes. Those guidelines included: moderate weight loss and physical activity; a focus on carbohydrates from fruits, vegetables, whole grains, legumes, low-fat milk and fiber-containing foods; avoiding low-carbohydrate diets (less than 130 grams per day) and high-protein diets; monitoring carbohydrates through carbohydrate counting, exchanges or experienced-based estimation; using the glycemic index (GI) for modest additional benefit; substituting sucrose-containing foods for other carbohydrates; consuming sugar alcohols and nonnutritive sweeteners within daily intake levels; limiting saturated fat to less than 7% of total calories, and dietary cholesterol to less than 200 mg per day; minimizing trans fats; and including two or more servings of fish per week.

Six major scientific organizations in the United States, Europe and Canada convened at the 2005 Nestlé Nutrition Workshop in Hangzhou, China, to review international guidelines for type 2 diabetes. Recommendations included distribution of total calories at 40% to 65% carbohydrates, 10% to 20% protein, less than 30% to 35% fat, and less than 10% saturated fat and trans fat combined. The workshop stressed boosting fiber intake up to 50 grams per day, and the concept of GI.

On the market 

Diabetic sugar-free foods were once heavily marketed to diabetics, but now they typically fall into the health and/or weight-loss segment. Although not necessary, such products can prove helpful, since nonnutritive sweeteners and polyols dont affect blood sugar.

There are great benefits for people in consciously using beverages and foods sweetened with no-cal sweeteners; for example, diet soda vs. regular soda. The benefits of sugar-free candy and cookies are not that great from either a calorie or glucose-lowering standpoint, says Warshaw.

Seeking superfoods

Researchers have looked at the influence of certain foods and nutrients on glucose control. Resistant starch or high-amylose foods may modify postprandial glycemic response, prevent hypoglycemia and reduce hyperglycemia. Researchers have studied magnesiums role in lowering inflammation and helping to prevent metabolic syndrome (Diabetes Care, 2006; 28:1438-1444). In one study on 17,413 men and women in Japan, scientists found that the more green tea and coffee participants drank, the less likely they were to get type 2 diabetes (Annals of Internal Medicine, 2006; 144:554-562). Additional research is required before nutritional recommendations can be made for such foods and nutrients.

Since 1965, over 369 studies have examined the role of chromium in diabetes and insulin resistance. Nutrition 21, Inc., Purchase, NY, submitted a petition to FDA in 2003 on chromium picolinates association with reduced insulin resistance, resulting in a qualified health claim: One small study suggests that chromium picolinate may reduce the risk of insulin resistance, and therefore possibly may reduce the risk of type 2 diabetes. FDA concludes, however, that the existence of such a relationship between chromium picolinate and either insulin resistance or type 2 diabetes is highly uncertain.

While Warshaw believes no magic dietary bullet for diabetes exists, she hopes the food industry can respond to diabetic consumer needs by creating healthy, convenient food options. With the type 2 diabetes population growing right along with Americas waistline, there may be plenty of opportunities to do so. 

Sharon Palmer is a registered dietitian with 6 years of experience in health-care and foodservice management. She writes on food and nutrition for newspapers, magazines, websites and books. Palmer makes her home in Southern California.