[pronut-hiv] American Diabetes Association Updates Guidelines for Medical Nutrition Therapy

["ProNut-HIV" <pronut-hiv@healthnet.org>]

December 28, 2007 * The American Diabetes Association (ADA) has updated its guidelines regarding medical nutrition therapy (MNT) to prevent diabetes, manage existing diabetes, and prevent or slow the rate of development of diabetes complications. The revised position statement, which is published in the January issue of Diabetes Care, updates those from 2002 and 2004, presenting evidence-based data published since 2000 and grading of recommendations according to the level of evidence available, based on the ADA evidence-grading system.

"The goal of these recommendations is to make people with diabetes and health care providers aware of beneficial nutrition interventions," write John P. Bantle, and colleagues from the ADA. "This requires the use of the best available scientific evidence while taking into account treatment goals, strategies to attain such goals, and changes individuals with diabetes are willing and able to make. Achieving nutrition-related goals requires a coordinated team effort that includes the person with diabetes and involves him or her in the decision-making process."
Because overweight and obesity are closely associated with development of diabetes, the position statement highlights this area of MNT. The US Department of Health and Human Services (HHS) recommends primary prevention interventions to delay or prevent the development of diabetes, using public health measures to decrease the prevalence of obesity and implementing MNT in persons with prediabetes. Secondary and tertiary prevention measures recommended by HHS include MNT for patients with diabetes to prevent (secondary) or control (tertiary) diabetes complications.

In addition to listing major nutritional recommendations and interventions for diabetes, the updated position statement stresses the importance of monitoring metabolic parameters, including glucose and glycated hemoglobin levels, lipids, blood pressure, body weight, and renal function, during therapy. Such monitoring will help evaluate the need for changes in MNT and thereby optimize outcomes. The authors note that many aspects of MNT require additional research.

Some of the specific recommendations include the following:
Individuals with prediabetes or diabetes should receive individualized MNT, preferably administered by a registered dietitian knowledgeable about the components of diabetes MNT (B). 
Nutrition counseling should be tailored to the personal needs of the individual with prediabetes or diabetes and his or her willingness and ability to make changes (E). 

Modest weight loss in overweight and obese insulin-resistant individuals has been shown to improve insulin resistance and is therefore recommended for all such individuals who have or are at risk for diabetes (A). 
In the short-term (up to 1 year), either low-carbohydrate or low-fat, energy-restricted diets may be effective for weight loss (A). 
Patients receiving low-carbohydrate diets should undergo monitoring of lipid profiles, renal function, and protein intake (in patients with nephropathy), and have adjustment of hypoglycemic therapy as needed (E). 
Physical activity and behavior modification aid in weight loss and are most helpful in maintaining weight loss (B). 
When combined with lifestyle modification, weight loss medications may help achieve a 5% to 10% weight loss and may be considered for overweight and obese individuals with type 2 diabetes (B). 
For some patients with type 2 diabetes and a body mass index of 35 kg/m2 or more, bariatric surgery can markedly improve glycemia (B). 
Primary prevention for individuals at high risk of developing type 2 diabetes should include structured programs targeting lifestyle changes, with dietary strategies of decreasing energy and dietary fat intakes. Goals should include moderate weight loss (7% body weight), regular physical activity (150 minutes/week) (A), dietary fiber intake of 14 g/1000 kcal, and whole grains comprising half of total grain intake (B). 
Intake of low-glycemic index foods that are rich in fiber and other vital nutrients should be encouraged (E), both for the general population and for those with diabetes. 
Data do not support recommending alcohol consumption to individuals at risk for diabetes (B). 
No nutritional recommendations exist to prevent type 1 diabetes (E). 
Secondary prevention, or controlling diabetes, should include a healthy dietary pattern emphasizing carbohydrate from fruits, vegetables, whole grains, legumes, and low-fat milk (B). 
A key strategy for achieving glycemic control is to monitor carbohydrate by counting, exchanges, or experienced-based estimation (A). Use of glycemic index and load may be modestly beneficial vs considering only total carbohydrate (B). 
Sucrose-containing foods should be limited but can be substituted for other carbohydrates or covered with insulin or other glucose-lowering medications (A). Glucose alcohols and nonnutritive sweeteners are safe within daily US Food and Drug Administration intake levels (A). 
Saturated fat should be limited to less than 7% of total energy (A), and trans fat should be minimized (E). In individuals with diabetes, dietary cholesterol should not exceed 200 mg/day (E). 
At least 2 servings of fish per week (except for commercially fried fish) are recommended for n-3 polyunsaturated fatty acids (B). 
Protein should not be used to treat acute or prevent nighttime hypoglycemia (A). High-protein diets are not recommended for weight loss (E). 
If adults with diabetes choose to use alcohol, intake should be restricted to 1 drink per day or less for women and 2 drinks per day or less for men (E) and consumed with food (E).

Other topics covered in this statement regarding secondary prevention include micronutrients in diabetes management; and nutritional interventions for type 1 and type 2 diabetes, pregnancy and lactation with diabetes, and older adults with diabetes.
Application of MNT to tertiary prevention, or treating and controlling diabetes complications, may be useful for microvascular complications, treatment and management of cardiovascular risk, management of hypoglycemia, management of acute illness, management of patients with diabetes in acute healthcare facilities, and management of patients with diabetes in long-term care facilities.
"MNT is important in preventing diabetes, managing existing diabetes, and preventing, or at least slowing, the rate of development of diabetes complications," the authors conclude. "It is recommended that a registered dietitian, knowledgeable and skilled in MNT, be the team member who plays the leading role in providing nutrition care. However, it is important that all team members, including physicians and nurses, be knowledgeable about MNT and support its implementation."

Diabetes Care. 2008;31(Suppl 1):S61-S78.