Medical nutrition therapy (MNT) has long been considered the cornerstone of diabetes management. No matter what type of diabetes you have, healthy eating is key to managing blood glucose, achieving a healthy weight, and normalizing blood lipid and blood pressure levels. Guidelines for diabetes MNT are put out by the American Diabetes Association (ADA) and are evidence-based, according to a review of the most recent scientific research. There is no one "diabetic diet" that is suitable for everyone with diabetes. Rather, the ADA recommends that you meet with a registered dietitian, who will address your individual needs, taking into account your personal and cultural preferences and your willingness to change.
Goals
According to the ADA, an overall goal of MNT for diabetes is to prevent diabetic complications---by focusing on the "ABCs". "A" (for A1C) refers a goal of keeping blood glucose levels as close to normal as is safely possible, with A1C less than 7%. "B" focuses on achieving blood pressure in a normal range---120/80---to reduce risk for micro and macrovascular disease. Microvascular disease is damage to tiny blood vessels and can lead to problems in the eyes, kidneys or feet. Heart disease is an example of macrovascular disease. The "C" of "ABCs" stands for cholesterol. The goal is to normalize lipid levels, including LDL ("bad") cholesterol <100 mg/dl. There are additional specific goals for youth, pregnant or lactating women, and older adults with diabetes.
Weight Control
A contributing factor to Type 2 diabetes is "insulin resistance", in which insulin is unable to effectively move glucose from the blood into the cells. If you are overweight or obese, modest weight loss---in the range of 7 percent body weight---has been shown to improve insulin resistance. The ADA recommends either low-carbohydrate or low-fat, calorie-restricted diets to achieve weight loss. Physical activity and behavior modification are also important components of a weight control program, especially in the maintenance phase.
Carbohydrate
The optimal mix of energy nutrients---carbohydrate, fat and protein---should be based on your individual needs. A registered dietitian will work with you to develop an individualized meal plan. Carbohydrates are the nutrient that have the biggest effect on your post-meal glucose level. They will generally make up 45 to 65 percent of total energy intake. They are found in milk, starches, fruit, and starchy vegetables---peas, corn, potatoes, legumes and winter squash. On average, a carbohydrate serving contains 60 to 80 calories and 15g carbohydrate. Examples include one cup milk or sugar-free yogurt; a medium fresh fruit; ½ cup canned fruit, fruit juice, or starchy vegetable; or one slice bread. Carbohydrate servings need to be individualized, but a good starting point would be to aim for three to four servings per meal and one to two for a snack.
Fat
Fat intake should be in the range of 20 to 35 percent of daily calories; again, this should be individualized based on your medical history and needs. ADA recommendations are consistent with those of the American Heart Association (AHA). Limit saturated fat to <7 percent of calories and avoid trans fats, as these increase LDL cholesterol. Replace them with poly- or monounsaturated fats. Include two fish meals per week to get Omega-3 fatty acids, which reduce risk of heart disease. Choose leaner cuts of meat, poultry without the skin and fish in place of higher fat meats; eat smaller meat portions; and choose vegetable alternatives, such as beans. Read food labels for saturated and trans fat content.
Protein
Protein usually makes up 15 to 20 percent of daily calories. The ADA does not recommend high protein diets for weight loss. Although they may produce short-term weight loss, there is not evidence to show that weight loss is maintained long-term. Also, the long-term effects of high protein intake on diabetes management and complications are not known. If you have kidney problems, your doctor may recommend a lower protein diet. Protein is found in high amounts in meat, dairy products and legumes. Aim to keep meat servings to 5 to 6 oz per day. Include two to three low-fat dairy servings each day. Opt for meat alternatives---legumes or tofu, for example---once or twice a week.
Alcohol
If you choose to consume alcohol, keep it to a moderate amount---one drink or less for women, two drinks or less for men---no more than twice a week. If you take insulin or an oral medication that increases insulin production, drink the alcohol along with a meal to reduce the risk of nighttime low blood sugar. Be aware of carbohydrates from soda, juice or mixers in a mixed drink.
Supplements
In a literature review published in "Diabetes Care", Yeh and colleagues concluded that there is insufficient evidence to demonstrate that any individual herb or dietary supplement is effective in managing diabetes. Both the ADA and AHA recommend against routine supplementation with antioxidants (vitamins A, C and E) since they have not been shown to be effective and long-term safety is a concern. Also, chromium supplementation is not recommended unless you have been diagnosed with chromium deficiency.
References
- Diabetes Care: Nutrition Recommendations and Interventions for Diabetes
- "Journal of the American Dietetic Association"; 2006-2007 American Diabetes Association Nutrition Recommendations; 2007
Member Comments