Medical Nutrition Therapy for Diabetes MellitusManual of Clinical Nutrition Management C- 3 Copyright © 20 13 Compass Group, Inc.
(1). Both the amount (grams) and type of carbohydrate in a food influence blood glucose levels (Grade I)* (1,4,5).
The total amount of carbohydrate consumed at meals and snacks influences the postmeal glucose response to
a greater extent than other macronutrients (Grade I) (4,5). There is a direct relationship between the amount of
carbohydrate in a meal, postmeal blood glucose response, and premeal rapid-acting or short-acting insulin
requirements to maintain desirable blood glucose goals (Grade I) (4,5). Therefore, the total amount of
carbohydrate consumed is a strong predictor of glycemic response, and monitoring the total grams of
carbohydrate (whether by use of exchanges or carbohydrate counting) remains a key strategy in achieving
glycemic control (Grade I) (1,4,5).
Studies have demonstrated that when persons with type 1 or type 2 diabetes mellitus consume a variety of
sugars or starches, there is no substantial difference in the glycemic response when the total amount of
carbohydrate remains constant (2,5). Sucrose intakes of 10% to 35% of total energy intake do not have a
negative effect on glycemic or lipid responses in persons with either type 1 to type 2 diabetes when sucrose is
substituted for isoenergetic amounts of starch (Grade I) (4). Based on these findings, sugar (eg, sucrose) intake
does not have to be avoided. Instead, sugar intake should be based on the total amount of carbohydrate
needed to achieve optimal metabolic control and the nutritional contribution to the diet. Foods containing
carbohydrate from whole grains, fruits, vegetables, and low-fat milk are important components and should be
included in a healthy diet for persons with diabetes mellitus (Grade I) (2,4).
Recently, the use of low–glycemic index foods or low-glycemic diets has received renewed interest. Factors
that influence the glycemic response to food include: the type and amount of carbohydrate, type of sugar,
nature of starch, cooking and food processing, as well as other food components (eg, fat and natural
substances that slow digestion—lectins, phytates, tannins, and starch-protein and starch-lipid combinations)
(2,6-9). Fasting and preprandial glucose concentrations, the severity of glucose intolerance, and the second
meal or lente effect are other factors that affect the glycemic response to food (2,10-13). Because of the variety
of factors that can influence a food’s glycemic response and the limited number of long-term studies, there is
still insufficient scientific evidence to support the use or nonuse of low-glycemic diets in improving metabolic
outcomes (Grade II) (1,2,4,14). A meta-analysis of low–glycemic index diet trials in diabetic subjects showed that
such diets produced a 0.4% decrement in hemoglobin A1C (A1C) when compared with high–glycemic index
diets (15). Some studies have shown short-term improvements in glycemic control by incorporating high-
fiber, low–glycemic index foods in meals or snacks (Grade I) (4). The glycemic index and/or glycemic load used
in conjunction with a consideration of total carbohydrate intake may provide greater benefits than
consideration of only the total carbohydrate intake (1,2). Therefore, the consideration of the glycemic index
may be helpful as an adjunct for select individuals. Individuals can determine the glycemic index’s usefulness
in maintaining their glycemic goals only by measuring their premeal and postmeal blood glucose levels
(1,14,15).
The amount of total carbohydrate intake should be individualized based on the individual’s energy goals to
achieve or maintain a desirable body weight, eating habits, and glucose and lipid goals (1-3). In type 2 diabetes
mellitus, an individual’s metabolic profile and the need for weight loss should be considered when
determining the carbohydrate and monounsaturated fat content of the diet (1,2). For weight loss, either a low-
carbohydrate or low-fat, energy-restricted diet may provide short-term effectiveness (for up to 1 year) (1,2).
For patients on low-carbohydrate diets, it is important to monitor lipid profiles, renal function, and protein
intake (in patients with nephropathy) and adjust hypoglycemia therapy as needed (2).
For additional information, refer to:
Energy Balance, Overweight, and Obesity in Diabetes in this section
Section III: Clinical Nutrition Management, Diabetes Mellitus: Fat Replacers and Nutritive/Nonnutritive
Sweeteners
Fiber
According to The American Diabetes Association and evidence-based nutrition practice guidelines fiber
consumption recommendations for people with diabetes are the same as for the general population (2,4). The
Dietary Reference Intake (DRI) recommends consumption of 14 g dietary fiber per 1,000 kcal, or 25 g for
adult women and 38 g for adult men (2,16). However, emerging evidence suggests persons with diabetes may
benefit from higher dietary fiber intake. Based on a current review of evidence, diets providing 30 to 50 g
fiber per day from whole food sources consistently produced lower serum glucose levels compared to low-
fiber diets (Grade III) (16). The addition of viscous dietary fibers slow gastric emptying rates, digestion, and
absorption of glucose to benefit immediate postprandial glucose metabolism and long-term glucose control in