Some people with diabetes think they can't eat foods containing sugars and starches (carbohydrates). But most experts now believe that people with diabetes should eat a diet high in carbohydrates and low in saturated fat.

The American Diabetes Association recommends that 45–65 percent of your total calories should come from carbohydrates. This may sound counterproductive, since people with diabetes need to control their blood glucose levels. However, carbohydrates are an important source of energy, water-soluble vitamins and minerals, and fiber, so restricting total carbohydrate intake to less than 130 g per day is not recommended. In addition, some experts have relaxed the allowance for ordinary sugar (sucrose) intake to as high as 10 percent of total calorie intake. That means people with diabetes can have a limited amount of sweets, chocolates, and desserts as part of a healthy meal plan.

Low-carb diets

Despite the more relaxed attitude toward carbohydrate intake, researchers continue to investigate low-carbohydrate, high-protein diets (that limit saturated fat) in people with diabetes. In one recent report, scientists asked a group of 16 people with type 2 diabetes to follow a diet that included just 20 percent of calories from carbohydrates. After 22 months, the participants had lost more than 17 lbs on average and cut their HbA1c levels from 8 to 6.9 percent.

However, the long-term effects of low-carbohydrate diets are not known. What's more, many doctors are concerned that low carbohydrate intake may cause ketosis and that high protein intake can damage the heart and the kidneys—all of which are already risks for people with diabetes. Studies have shown that people who have diabetes and chronic kidney disease may help prevent further damage to their kidneys by reducing the amount of protein in their diet. The American Diabetes Association does not recommend low-carbohydrate diets in the management of diabetes.

Glycemic index

A number of books and diet doctors advocate low-glycemic-index diets. Proponents of these diets claim that foods with a low glycemic index (such as whole grains and most fruits and vegetables) are more healthful than foods with a high index (such as white bread, candy, and soda) because they do not produce as rapid an increase in blood glucose levels when eaten.

Based on this reasoning, proponents say that low-glycemic-index foods should comprise the greatest proportion of your carbohydrate intake. The glycemic index can encourage better carbohydrate choices, such as consuming more fiber and fewer high-sugar foods, but it may also lead to worse choices, such as avoiding carbohydrates altogether and eating fattier foods.

Sugars

Both the amount of carbohydrates (number of grams) and the type of carbohydrates you eat affect your blood glucose levels, although the total amount of carbohydrates you consume is more important than the type of carbohydrate.

If sugar is used as a replacement for other carbohydrates—gram for gram (calorie for calorie)—and is not simply added to the diet, people with diabetes can safely eat foods that contain sugar. The downside is that sugary foods often contain "empty calories," whereas starchy foods are more nutritious because they also supply vitamins, minerals, and fiber.

Sugar is available in many forms—white, brown, granulated, and confectioners'. The chemical name for these sugars is sucrose. Many food products contain other types of sugar, all having chemical names that end in –ose, such as glucose (also called dextrose), fructose (in fruits and honey), lactose (in milk products), and maltose (in starchy foods).

During digestion, sucrose, lactose, and maltose are broken down into glucose and other simpler types of sugars. Some of these sugars have a lower glycemic index and reach the bloodstream more slowly than other sugars, but they still raise blood glucose levels. Unfortunately, some foods that are labeled "safe for diabetics" just replace sucrose with fructose, maltose, or other forms of sugar. That's why it's important to check food labels for hidden sugars such as honey, corn syrup, molasses, and ingredients ending in the telltale –ose.

Sugar alcohols

Also watch for sugar alcohols with names that end in –ol, such as sorbitol, mannitol, xylitol, and maltitol. These sweeteners are chemically related to alcohol, but they have no alcoholic effects. They are carbohydrates that are converted to ordinary sugar during digestion.

Sugar alcohols are used in many products labeled as "low carb," "low sugar," or "sugar free." Although they have a lower glycemic index than ordinary sugar, don't be fooled. Sugar alcohols have calories and will raise your blood glucose level. They are not "free foods" (a free food is any food or drink that contains less than 20 calories or less than 5 g of carbohydrate per serving). In addition, many low-carb foods that are sweetened with sugar alcohols are high in fat, and large quantities of sugar alcohols often cause diarrhea.

Noncaloric sugar substitutes

Some "sugar-free" beverages and packaged foods really are what they say. That's because they contain one of the products the U.S. Food and Drug Administration (FDA) has approved as non-nutritive sweeteners: saccharin (Sweet-'N Low, Sweet Twin, Necta Sweet), aspartame (Equal, NutraSweet, NatraTaste), acesulfame-K (Sunett, Sweet One), sucralose (Splenda) and neotame. According to the American Diabetes Association, all of these noncaloric sugar substitutes have undergone rigorous testing and are safe for consumption by people with diabetes.

Publication Review By: Written by: Christopher D. Saudek, M.D.; Simeon Margolis, M.D., Ph.D.

Published: 20 Apr 2009

Last Modified: 11 Sep 2015