We are still on the path of sharing the new American Diabetes Association’s nutritional guidelines for all of us with diabetes. To that end, here is part 2 of our two part series. Those of you on Medicare, please pay attention because as of Jan 02 your Medicare will pay for nutritional therapy if you have diabetes. We have had many questions over the years about this very subject so we hope that with this information you will be able to have meaningful discussions with your nutritionist and physician about your dietary needs. Read on.
CARBOHYDRATES AND SWEETENERS
The percent of calories from carbohydrates that is suggested for diabetic diets varies with the individual’s eating habits and glucose and lipid goals. For most of the last century it was believed that simple sugars should be avoided by diabetics based on the assumption that sugars are rapidly digested and absorbed and therefore raise blood glucose levels more than other starches.
There is little scientific evidence that supports this assumption. Fruits and milk have been shown to have a lower glycemic response than most starches, and sucrose produces a glycemic response similar to that of bread, rice, and potatoes. Although various starches do have different glycemic responses, from a clinical perspective first priority should be given to the total amount of carbohydrate consumed rather than the source of the carbohydrate.
Scientific evidence has shown that the use of sucrose as part of the total carbohydrate content does not impair blood glucose control in people with type 1 or type 2 diabetes. Sucrose and sucrose-containing foods must be substituted for other carbohydrates gram for gram and not simply added to the meal plan. In making these substitutions, it is important to also add nutrients that often occur with sucrose such as fat.
Fructose does produce a smaller rise in blood glucose than other starches, however it comes with potential adverse effects of consuming large amounts of this sweetener. These include that consuming 20% of calories in fructose has an effect on serum cholesterol and LDL cholesterol, so that fructose is not suggested as a sweetening agent in the diabetic diet.
Although people with dyslipidemia should avoid consuming large amounts of fructose, there is no reason to recommend that people with diabetes avoid eating fruits and vegetables in which fructose occurs naturally. Moderate consumption of fructose-sweetened food is not discouraged, but to say that fructose is healthier than other sweeteners is not a true statement.
Other nutritive sweeteners
Nutritive sweeteners other than sucrose and fructose include sugar alcohols (polyols) that produce a lower glycemic response than sucrose and other carbohydrates. Starch hydrolysates are formed by the partial hydrolysis and hydrogenation of edible starches, thus becoming polyols.
Although the exact caloric value of sugar alcohols vary, they average ~2kcal/g compared with 4kcal/g from other carbohydrates. Evidence is limited to suggest that this can be expected to contribute to a major reduction in total calories or in the total carbohydrate content of the daily diet. Furthermore, excessive amounts of polyols may have a laxative effect.
The calories and carbohydrate content from all nutritives must be accounted for in the meal plan, and have the potential to affect blood glucose levels.
Saccharin, aspartame, acesulfame K and sucralose are approved for use in the US by the Food and Drug Administration (FDA). For all food additives, including nonnutritive sweeteners, the FDA determines an acceptable daily intake (ADI), which is defined as the amount of food additive that can be consumed on a daily basis over a person’s lifetime without any adverse effects and includes a 100-fold safety factor. Actual intake by people with diabetes for all nonnutritive sweeteners is well below the ADI.
It has been proposed that foods that contain naturally occurring resistant starch (cornstarch) or foods modified to contain more resistant starch(high amylase cornstarch) may modify postprandial glycemic response, prevent hypoglycemia, reduce hyperglycemia, and explain differences in the glycemic index of some foods. However, there are no published long-term studies in subjects with diabetes to prove benefit from the use of resistant starch.
Dietary fiber may be helpful in the treatment or prevention of constipation and several gastrointestinal disorders, including colon cancer, provides satiety value to the diet; large amounts of soluble fiber have a beneficial effect on serum lipids. People with diabetes would be as amenable to these effects as those without diabetes. Although selected soluble fibers are capable of inhibiting absorption of glucose from the small intestine, in the amounts likely to be consumed from foods, the clinical significance of this effect on blood glucose levels is probably insignificant. Therefore, recommendations for people with diabetes are the same as for the general population related to fiber and a healthy diet. Daily consumption of a diet containing 20-35 g dietary fiber from soluble and insoluble fibers from a wide variety of food sources is recommended.
People differ in their sensitivity to sodium and its effect on blood pressure. Because it is impractical to assess individual sodium sensitivity, intake recommendations for people with diabetes are the same as for the general population. Some health authorities suggest no more than 3,000 mg/day of sodium for the general population, while other authorities recommend no more than 2,400 mg/day. For people with mild to moderate hypertension <2,400 mg/day of sodium is recommended. For people with hypertension and neuropathy, <2,000 mg/day of sodium is recommended.
Vitamins and Minerals
When dietary intake is adequate, there is generally no need for additional vitamin and mineral supplementation for the majority of people with diabetes. Although there are theoretical reasons to supplement with antioxidants, there is little confirmatory evidence at present that such therapy has any benefits. Because diabetes may be a state of increased oxidant stress, there has been some interest in prescribing antioxidant vitamins to diabetics. As of today, megadoses of vitamin C, E selenium, beta carotene and other carotenoids have not shown protection against cardiovascular disease, diabetes, or cancer. Because of long term efficacy and safety issues, they are not recommended.
A daily intake of 1,000-1,500 mg of calcium, especially in older people with diabetes is recommended. It appears to be safe and likely to reduce osteoporosis in older persons. The role of vanadium salts in diabetes has been explored, but there is no clear evidence of efficacy and there is a potential of toxicity. A variety of herbal preparations have been shown to have a very modest effect on glycemia. However, commercially available products are not well standardized, and vary in content of active ingredients. They also have the potential of interacting with medications. Therefore, if you decide to try herbal supplements, make sure to tell your physician.
The only known circumstances in which chromium replacement has any beneficial effect on glycemic control is for people who are chromium deficient as a result of long-term chromium-deficient prenatal nutrition. However, it appears that most people with diabetes are not chromium deficient and therefore, chromium supplementation has no known benefit.
Similarly, although magnesium deficiency may play a role in insulin resistance, carbohydrate intolerance, and hypertension, the available data suggest that routine evaluation of serum magnesium levels is recommended only on persons who are at high risk for magnesium deficiency. Levels of magnesium should be replaced only if hypomagnesium can be demonstrated.
Potassium loss may be sufficient enough to warrant dietary supplementation in patients taking diuretics. Hyperkalemia sufficient to warrant dietary potassium restriction may occur in patients with renal insufficiency or hyporeninemic hypaldosteronism or in patients taking angiotensin-converting enzyme inhibitors.
To summarize, today there is no one “diabetic” diet. The recommended diet can only be defined as a nutrition prescription based on assessment and treatment goals and these diets should be individualized with consideration given to usual eating habits and lifestyle factors.
Nutrition recommendations are then developed and implemented to meet treatment goals and desired outcomes. Monitoring metabolic parameters, including blood glucose levels, glycated hemoglobin, lipids, blood pressure, body weight and renal function as well as quality of life, is crucial to ensure successful outcomes for individual people with diabetes.
Furthermore, it is essential that ongoing nutritional self-management education care must be provided to people with diabetes so that they are truly an important member of the treatment team. We all know that this is the best way to give the person with diabetes the best and most fulfilling lifestyle possible-thus the name of our web site. Keep reading and demanding services you need to make the most informed decision about your life.