O Hamdy, D Zweiefelholer
Curr Diab Rep (2010) 10:159-164
The global increase in overweight and obesity has led to a parallel increase in the number of type 2 diabetics. Weight gain is also a side effect of many diabetes medications, and individuals on insulin treatment find it more difficult to lose weight than others. Weight loss as a treatment for type 2 diabetes can delay the need for medication, reduce cardiovascular risk and improve quality of life. Studies show that a modest weight loss of 7% over 6 months along with increased physical activity improves insulin sensitivity, endothelial function and several markers of inflammation and coagulation in obese patients with and without type 2 diabetes.
Overweight and obese individuals with type 2 diabetes who wish to lose weight face significant challenges. However, several recent studies show that weight reduction in type 2 diabetes is possible using meal replacement products in conjunction with a structured diet plan.
Meal replacement products have been found to be useful when beginning a weight loss program or for weight management since they are low in calories while providing adequate nutrition. Meal replacement products are fortified with vitamins and minerals, to prevent the deficiencies in essential micronutrients that are often seen in low calorie diets. Meal replacement products are available in several different flavors and types (bars, beverages, soups) which increases acceptance and adherence. Meal replacements are used as replacements for both meals and snacks. Type 2 diabetics who use meal replacement products need to monitor their blood sugar levels closely and may need to adjust their diabetes medicine. This review article shows results from both clinical studies and clinical practice.
Meal replacement products are used in conjunction with a structured eating plan to replace 1-2 meals/day. In the following studies such meals usually provide 190 to 350 kcal/portion and may be supplemented with 100-200 kcal (fruit, nuts) for meals or snacks. In Sweden, the calorie content of what are known as meal replacement products is between 200 and 400 kcal/portion, according to EU directives and National Food Agency guidelines.
Results and discussion:
One study that compared the nutrient content of a diet plan with meal replacements with traditional low-calorie food, in which the composition of both diets met recommendations, showed that the diet with traditional food was significantly lower in 9 essential vitamins and minerals. Several studies have shown similar results in which the vitamin and mineral content, which is important for metabolism and bone health (vitamin B, iron, calcium and magnesium), were less than the recommended daily intake.
Meal replacements are a simple and effective way to avoid loss of nutrients and provide nutrient adequacy, especially macronutrients, while reducing calorie intake.
According to Heymsfield, weight loss using meal replacements compared with regular food for one year produced a weight loss of 7-8% in meal replacement diets, compared with a weight loss of 3-7% with traditional food. The dropout rate in the study was lower in the group treated with meal replacements.
To maintain weight loss, Vazques showed in one study that it is more effective to use meal replacements for one meal per day than to eat traditional food. The group using meal replacements lost 3.2% +/- 3.7% of their weight, while the group eating traditional food lost 1.3% +/- 3.6% after 6 months.
The primary task of meal replacements is to reduce exposure to the number of food choices and to eliminate poor food choices. Meal replacements provide a form of structured eating that is easier to use in dietary treatment and is intended to control portion size and high-calorie eating.
A meta-analysis shows that weight loss among diabetics was lower at 1 year than after 3 months, indicating that lifestyle changes decline to a greater extent in diabetics than in healthy overweight and obese individuals, even when using meal replacements. This finding may also be due to the progression of diabetes and the need for higher doses of diabetes medication such as insulin, which may contribute to weight gain. Diabetics may need more support over time to maintain their weight goals.
One of the largest weight studies involving diabetes using meal replacements for weight reduction is currently underway, the Look AHEAD study. Participants were randomized to two groups, one of which requires intensive lifestyle changes and the option to use 1-2 meal replacements per day. The other group received standard diabetes support and education. The study will continue for 10 years, but the first results after 4 years have been published and show that the first group achieved an 8.6% weight loss, while the other group achieved a 0.7% weight loss. HgbAc1 declined 0.64% and 0.14% respectively in the two groups. This was also reflected by a reduction in glucose-lowering medications in the first group, while use of medication increased in the other group. The first group showed better adherence to meal replacements, more physical activity and better compliance to diabetes treatment. The greater the confidence in the meal replacements, the higher the odds for achieving weight loss goals.
In long-term weight loss, should the patient begin to gain weight, meal replacements combined with physical activity may be used to get the patient back on track.
Several studies show that meal replacements along with a structured eating plan present a successful formula for short-term and long-term weight loss in type 2 diabetic patients with overweight and obesity. Nutrient adequacy requirements can also be satisfied to a greater extent by a diet combined with meal replacements, when compared with traditional low-calorie food alone.
Meal replacement products are available in several different flavors and types, which increases acceptance and adherence. Meal replacements comply with EU directives and NFA guidelines and can be used for type 2 diabetics. Type 2 diabetics who use meal replacement products need to monitor their blood sugar levels closely and may need to adjust their diabetes medicine.
Relapse with respect to lifestyle changes is more common in type 2-diabetics than in other people with obesity. It is therefore particularly important to set goals and to provide more guidance and commitment to this patient group. Achieving weight loss in patients with type 2 diabetes requires multidisciplinary support from doctors, diabetes nurses and dietitians.