News & Research

Anderson JW, Randles KM, Kendall CW, et al.: Carbohydrate and fiber recommendations for individuals with diabetes: A quantitative assessment and meta-analysis of the evidence. J Am Coll Nutr23:5-17, 2004.

What is the problem, and what is known about it so far?

Diabetes is a growing problem throughout the world. People with diabetes need to know how different foods affect their body and the illness. Doctors need scientific evidence to figure out what to tell patients about diet, especially about carbohydrates and fiber.

Who did the researchers study?

Researchers searched the medical literature for similar studies over the past 25 years. They looked at recommendations from diabetes and cardiovascular disease experts from around the world.

How was the study done?

Researchers looked at information on things including weight loss, carbohydrates, fiber, protein, fat, cholesterol, and glycemic index (a measure of how quickly a food affects the glucose in your blood).

What did the researchers find?

High-carbohydrate, high-fiber meals improved blood glucose and glycated hemoglobin (A1C) levels (a measure of long-term blood glucose control). These diets also improved blood lipid (fat) levels. Low glycemic-index diets (including foods such as yams, bananas, prunes, and milk) improved blood glucose levels and insulin response. They also reduced blood cholesterol.

What were the limitations of the study?

Most of the studies the researchers looked at were short-term, with the longest lasting 90 days. This may not be long enough to get an accurate picture. Studies disagreed over recommendations on weight loss, glycemic index use, and how much fiber and protein people with diabetes need.

What are the implications of the study?

The researchers came up with the following recommendations for people with diabetes:

• Keeping a body weight is important. Body mass index (BMI) should be 25 or less.
• Carbohydrate should make up of 55%–65% of a person's calories.
• Four vegetable servings per day are recommended.
• People should eat as much fruit as they want.
• People should eat 25-50 grams of fiber every day. High-fiber foods include oats and barley; whole-grain breads, cereals, and pastas; brown rice, dry beans, peas, and lentils; nuts, fruits, and vegetables.
• Protein should make up 11%-18% of a person's diet. More protein should come from soy and less from animals.
• Fat should make up 25%-30% of a person's diet.
• The amount of cholesterol a person eats should be less than 200 mg per day.
• People should eat foods with a low-glycemic index (such as prunes, milk, yams, and bananas).
• Glycemic index should be used when teaching people about nutrition.