Are liquid meal replacements to treat diabetes effective for people with type 2 diabetes and obesity?
The evidence for liquid meal replacements to treat diabetes has not been summarized. The objective was to synthesize the evidence of the effect of liquid meal replacements on cardiometabolic risk factors in individuals with overweight/obesity and type 2 diabetes.
This systematic review and meta-analysis of nine trials including 961 patients investigated the effect of liquid meal replacements on cardiometabolic risk factors in patients with type 2 diabetes who were overweight/obese. Modest reductions in body weight, BMI, body fat, waist circumference, HbA1c, fasting glucose, fasting insulin, and blood pressure were determined.
Modest and sustained weight loss has been shown to reduce the need for glucose-lowering medications and improve glycemic control in overweight/obese individuals with type 2 diabetes. However, many overweight/obese individuals with type 2 diabetes face challenges in achieving weight loss. Metabolic, psychological, and behavioral factors affect the ability of people with diabetes to lose weight. Many pharmacological agents used in the treatment of diabetes also directly contribute to weight gain through their glucose-lowering mechanisms (i.e., sulfonylureas, meglitinides, and thiazolidinediones). The use of liquid meal replacements within a structured dietary plan may offer a viable solution. Liquid meal replacements provide a mixture of carbohydrates, fat, and protein, along with added vitamins and minerals, in ready-to-drink form or powder formulas that require mixing. They are frequently used to replace one or two main meals each day and are often supplemented with fruits, vegetables, and nuts during or between meals to achieve the targeted daily caloric intake.
The American Diabetes Association clinical practice guidelines include recommendations for the use of meal replacements for diabetes management. However, the European Association for the Study of Diabetes (EASD) has not made any specific recommendations for the use of liquid meal replacements. To update the recommendations for the role of liquid meal replacements in diabetes management, the Diabetes and Nutrition Study Group (DNSG) of the EASD commissioned this systematic review and meta-analysis using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to summarize the available evidence from randomized controlled trials (RCTs) investigating the effect of liquid meal replacements as part of a weight loss diet in comparison with traditional low-calorie weight loss diets on cardiometabolic risk factors in overweight/obese individuals with type 2 diabetes.
Data sources included MEDLINE, EMBASE, and the Cochrane Library through 10 December 2018, randomized trials of ≥2 weeks assessing the effect of liquid meal replacements in weight loss diets compared with traditional weight loss diets on cardiometabolic risk factors in overweight/obese subjects with type 2 diabetes.
Nine trial comparisons (N = 961 [median follow-up 24 weeks]) met eligibility criteria. Mean differences were for body weight -2.37, body fat -1.66%, waist circumference -2.24 cm, HbA1c -0.43%), fasting glucose -0.63 mmol/L, fasting insulin -11.83 mmol/L, systolic blood pressure -4.97 mmHg, and diastolic blood pressure -1.98 mmHg. There was no effect on blood lipids.
From the results it was concluded that liquid meal replacements in weight loss diets lead to modest reductions in body weight, BMI, and systolic blood pressure, and reductions of marginal clinical significance in body fat, waist circumference, HbA1c, fasting glucose, fasting insulin, and diastolic blood pressure.
- Liquid meal replacements in weight loss diets led to modest reductions in cardiometabolic risk factors for patients with overweight or obesity and type 2 diabetes
- Modest weight loss has been shown to improve glycemic control and blood pressure
- Individuals with overweight or obesity and type 2 diabetes on a diet incorporating meal replacement shakes such as SlimFast or Glucerna SR lost a mean of 2.7 kg more than those on a conventional diet
Diabetes Care 2019 May; 42(5): 767-776.https://doi.org/10.2337/dc18-2270