Meal replacements offer promise for patients with obesity. 

From 1999-2020, the United States witnessed a 37.4 percent increase in obesity among adults, and patients with obesity are at an elevated risk of developing cardiovascular disease and type 2 diabetes.¹ In addition to the increased risk for comorbidities, annual medical costs for patients with obesity are higher than healthy-weight counterparts.¹ According to the Centers for Disease Control, medical costs in 2019 for adults with obesity was almost two thousand dollars more than healthy weight counterparts,² with the estimated annual cost for treating patients with obesity close to 173 billion dollars. One way to reduce the health risks and financial burdens for patients with obesity is to integrate meal replacements (MR) into a clinically supervised program.³ 

A meal replacement is a prepared liquid (for example, pudding shakes or drinks) or discrete foods (for example, protein bars) that are used in place of one or two daily meals. Medically prescribed meal replacements are designed to deliver nutritional benefits to patients with obesity, providing them with the vitamins and minerals needed as part of a healthy diet.⁴   Including meal replacements as part of a clinically supervised weight management program can help reduce the risk of comorbidities such as cardiovascular disease and type 2 diabetes for patients with obesity.

Evidence for the Efficacy of Meal Replacements 

The Almased Concept against Overweight and Obesity Related Health Risk (ACOORH) study investigated the effect of liquid meal replacements in two populations of persons with obesity: overweight persons who were prediabetics and overweight persons with cardiovascular risk factors.^5,6  In the ACOORH study investigating the effects of meal replacements on prediabetes, participants were randomly assigned to a control group with the lifestyle intervention only (N=45) or a lifestyle intervention plus meal replacement (N=96). The experimental group used meal replacements, beginning with replacing three meals per day during week one, two meals per day during weeks two-to-four, and one meal per day during weeks five through 26. Participants in the meal replacement group with the lifestyle intervention significantly reduced their prevalence of prediabetes compared to the control group. The prediabetes conversion rate to normoglycemia was also associated with reductions in body weight and fat mass. 

In another randomized control trial of 961 patients with obesity who were predominantly overweight and living with type 2 diabetes, adding a meal replacement as part of their weight loss strategy resulted in meaningful reductions in body weight, BMI, and systolic blood pressure compared to traditional low calorie weight loss approaches.⁷ 

Even at the one-year mark, patients with obesity saw reductions in comorbidities and increased weight loss. This suggests that including a liquid meal replacement is an efficacious option in the context of common comorbidities such as prediabetes, diabetes, and cardiovascular risk factors.

Meal Replacements Compared to Other Weight Loss Interventions 

In a systematic review and meta-analysis of the effectiveness of meal replacements for weight loss, meal replacements were compared across five contexts: (1) MR vs diet only, (2) MR diet + support vs diet + support, (3) MR diet + support vs diet, (4) MR diet + enhanced support vs diet + support, and (5) MR diet + support vs minimal intervention. Across all contexts the mean weight change for participants was, on average, higher when MRs were included as part of the program.⁴ 

Participants who received a meal replacement intervention continued to lose weight, even at the two-year mark, compared to their diet-only counterparts. In fact, the efficacy of meal replacements is so strong that in each of the five contexts noted above, all the studies in the meta-analysis⁴ reported the meal replacement intervention was, in almost all cases, superior to the comparison groups. 

Conclusion

Obesity is a challenging disease to treat. Patients with obesity experience higher costs for medical care, increased risks of comorbidities as well as numerous lifestyle challenges. Meal replacements offer health care providers another strategy for helping their patients with obesity achieve their weight loss goals while also mitigating their risk for cardiovascular disease and type 2 diabetes. Meal replacements should be considered as part of the clinical standard of care for patients with obesity.

Sources:

1. Direct medical costs of obesity in the United States and the most populous states
2. Centers for Disease Control and Prevention  
3. Position of the American Dietetic Association: Weight management
4. A systematic review and meta‐analysis of the effectiveness of meal replacements for weight loss 
5. Prediabetes conversion to normoglycemia is superior adding a low-carbohydrate and energy deficit formula diet to lifestyle intervention—A 12-month sub-analysis of the ACOORH trial 
6. Meal replacement by formula diet reduces weight more than a lifestyle intervention alone in patients with overweight or obesity and accompanied cardiovascular risk factors—The ACOORH trial 
7. The effect of liquid meal replacements on cardiometabolic risk factors in overweight/obese individuals with type 2 diabetes: a systematic review and meta-analysis of randomized controlled trials