Do Meal Replacement Shakes Work? Examining Weight Loss Claims

High-protein meal replacements can aid in weight loss by creating a calorie deficit while providing essential nutrients. Research shows significant weight-loss benefits when used strategically as part of a broader lifestyle approach. They work best as partial meal replacements, alongside balanced nutrition and exercise. 

Losing weight is not always easy. Given the hectic pace of modern life, people have turned to dubious diets or weight-loss supplements that are not backed by science. By contrast, meal replacements have been studied extensively and offer a practical, evidence-based solution for weight management. 

High-protein meal replacement shakes, in particular, are effective, convenient and nutrient-rich and can help control hunger while supporting a balanced diet. Let’s dig deeper into why these weight-loss shakes work better than typical calorie-restricted diets, according to scientific evidence.

There’s nothing magical about meal replacements, and they’re not as bland or boring as food replacements in science fiction may suggest. Today, there are a hundred or more ways to prepare meal replacement shakes that taste great and fill you up for hours. 

Let’s break down four science-backed benefits of meal replacement shakes:

Losing weight requires a simple, proven principle: consuming fewer calories than you burn. While this sounds straightforward, many people struggle with portion control or tracking their calorie intake consistently. This is where meal replacement shakes shine. These portion-controlled drinks are premeasured to deliver just the right number of calories, making it easier to maintain a caloric deficit without the guesswork or the risk of overeating. 

However, simply slashing calories without considering nutritional balance can lead to deficiencies and a negative impact on your health. That’s why high-quality meal replacements are designed to be nutrient-dense and are often fortified with essential vitamins and minerals to ensure you’re still meeting your body’s needs while cutting back on calories. This balance helps promote sustainable weight loss without compromising your overall well-being.

Protein is the most satiating macronutrient – meaning that it keeps you feeling full for longer than carbohydrates or fats. Consistently getting the right amount of protein each day is crucial for controlling hunger. Plant- and animal-based proteins tend to be some of the main ingredients in many meal replacements. 

Here’s how protein supports weight loss: 

• Satiety: Protein helps suppress appetite by reducing hunger hormones like ghrelin while increasing hormones that signal fullness. 
• Calorie Burn: Protein has a high thermic effect, meaning that your body burns more calories digesting protein compared to carbs or fats. 
• Lean Body Mass: When paired with resistance exercise, high-protein meal replacements help maintain or build lean muscle, which supports fat loss. Muscle tissue burns more calories at rest than fat, boosting your metabolism over time. 
• Hormone Regulation: Protein stimulates gut hormones that help regulate blood sugar and insulin levels, ultimately aiding in hunger control after eating.

Meal replacement shakes often have a low glycemic index (GI), meaning that they cause a slower, steadier rise in blood sugar. Foods with a high GI can cause blood sugar to spike and then drop sharply, leaving you feeling tired and hungry. In contrast, low-GI foods, including many meal replacement shakes, release sugar into the blood gradually, helping you feel full for longer. 

Some meal replacement formulations also provide fiber, which further slows digestion and contributes to the feeling of fullness. 

By slowing digestion, low-GI options like meal replacements, fruits, vegetables, and whole grains help curb appetite. Even with fewer calories than a traditional meal, a low-GI meal replacement shake can effectively suppress hunger and support weight management.

Beyond their nutritional benefits, meal replacements simplify weight management by helping you control your food intake for one or two meals a day. This simplicity supports positive behavioral changes that are just as important as the nutritional advantages, particularly compared to typical or fad diets. 

A four-year study conducted by the Medicine Department of the University of Ulm in Germany (which did not involve Herbalife products) identified six key reasons why meal replacement diets are so effective for weight loss: 

1. Convenience – Preparing healthy meals can be time-consuming, which is a common barrier to losing weight. Meal replacements offer a simple, time-saving solution. 
2. Increased Compliance – Meal replacements reduce the temptation to indulge in unhealthy foods, making it easier to stick to your dietary goals. 
3. Regular Eating Pattern – Establishing a routine with regular meals can improve energy levels and prevent excessive hunger. Meal replacements help create and maintain this structure. 
4. Accuracy of Calorie Estimation – Accurately tracking calorie intake can be challenging. Meal replacements provide a precise, consistent way to meet calorie goals when prepared as recommended. 
5. Quality of Food Consumed – Cutting calories often leads to nutrient deficiencies. Meal replacements are usually fortified with vitamins, minerals, protein and fiber to help fill these gaps. 
6. Positively Affects Self-Monitoring – Tracking your dietary intake improves awareness of eating habits. Meal replacements are easy to monitor, making it simpler to stay accountable.

Yes, meal replacement shakes are healthy when made with high-quality ingredients and consumed as recommended. Many are designed to be nutrient-dense, offering a balanced mix of proteins, healthy fats and essential vitamins and minerals – all while being relatively low in calories. 

Nutrient density refers to the ratio of nutrients to calories in a food. Foods with high-nutrient density offer more nutrition per calorie, while those with low nutrient density – like cookies, cakes or sugary soft drinks – provide fewer nutrients and are often high in sugar and fat. 

When formulated properly, meal replacement shakes are nutrient-dense, making them a healthier choice compared to typical meals or snacks that are often loaded with sugar, unhealthy fats and empty calories. 

Research shows that meal replacement diets, especially those rich in protein, can improve diet quality for individuals who are overweight or obese. A study on high-protein partial meal replacement diets revealed that participants experienced: 

• Significant decreases in fat, sodium and cholesterol intake 
• Increased protein and fiber consumption 
• Improved micronutrient intake, including vitamins D, calcium and potassium 
• Significant reduction in sodium intake 

For those struggling to maintain a balanced diet, meal replacements can help improve overall nutrition. When combined with healthy eating and regular physical activity, they can be an effective tool for weight management and enhanced diet quality.

Diet shakes have been around for decades, and it's understandable that some may be skeptical about their effectiveness or potential for over-reliance. Critics may dismiss them as just another "fad diet," but meal replacement shakes have proven to be a reliable tool in weight management, used in both consumer and clinical settings.

Taste can vary by brand, and some shakes may feel bland or overly artificial, especially if the flavor options are limited to just vanilla or chocolate. To enhance both flavor and texture, try mixing in fruits, vegetables, nuts or seeds. Experiment with different shake recipes to find combinations that work for you.

Consider the cost and time it takes to prepare a healthy, nutritious meal. Meal replacement shakes offer a cost-effective, convenient option, especially for busy lifestyles. When bought in powder form, a single serving becomes more affordable than the average meal, factoring in the cost of ingredients, preparation and time. For those on the go, they provide a quick, healthy choice without the need for cooking.

Meal replacements are designed to support weight management and balanced nutrition, typically as partial replacements rather than total replacements for all meals. For most consumers, this means replacing one or two meals daily while incorporating whole foods and snacks to meet calorie and nutrient needs. For example, Herbalife Meal Plans suggest replacing one meal with a shake for weight maintenance or two meals for weight loss. Whole foods and protein-rich snacks are still essential to provide variety, satiety and key nutrients. Total diet replacement using weight-loss shakes should only be done under medical supervision.

Yes, meal replacement shakes are safe for healthy individuals when used as directed. Those who are pregnant or have specific medical conditions should consult a health care provider before using them. And if you have dietary restrictions or food allergies, be sure to check the label for any allergens or ingredients that may not meet your needs. Many meal replacements offer plant-based options, including soy, non-soy or vegan alternatives, to accommodate various preferences.

Researchers from the University of Oxford published a systematic review and meta-analysis of meal replacements for weight management, examining 14 studies that compared the effect of weight-loss interventions that incorporated meal replacements to those of alternative interventions. 

The study concluded that meal replacements were superior to standard dieting and calorie restriction: 

• Participants assigned to a meal replacement diet lost an additional 1.44 kilograms (3.17 pounds) in one year compared to a diet-only approach. 
• Participants in the meal replacement group who joined behavioral weight-loss programs to enhance their effect had a greater weight loss of 6.13 kilograms (13.51 pounds) within the group. 

This finding underlines the value of social support, as these types of programs make it easier for people to adhere to a reduced energy diet. The structure and external control associated with these programs may also promote adherence. 

Someone simply purchasing meal replacements from a grocery store can easily grow tired of the same flavor and give up, whereas a behavioral program or supportive community will lead to greater adherence.

Obesity is a chronic and complex disease affecting millions globally, contributing to numerous health complications and increased health care costs. More and more clinicians now recognize the effectiveness of meal replacements as part of medical nutrition therapy for weight management. 

Recent research underscores the benefits of meal replacements, particularly in low-calorie diets and very-low-calorie diets, making them a valuable tool in obesity treatment strategies. 

A narrative review of clinical evidence highlights several important findings about meal replacements: 

• Significant Weight Loss: Total diet replacement programs, where meal replacements provide all dietary energy, result in an average weight reduction of approximately 10 kilograms (22 pounds) over 12 months. 
• Twice the Effectiveness of Food-Based Diets: Meal replacement-based diets can achieve nearly double the weight loss compared to food-only calorie-restricted diets. 
• Improved Cardiometabolic Health: Meal replacements have been shown to reduce blood pressure, improve blood sugar control and positively impact lipid profiles and fatty liver conditions. 
• Better Adherence: Meal replacements help manage cravings and hunger, likely due to mechanisms such as ketosis and simplified food choices, making them easier to follow consistently. 
• Quality of Life Improvements: Studies report enhanced physical functioning and overall well-being among those using meal replacements in structured weight management plans.

Several clinical guidelines around the world now support incorporating meal replacements into weight-loss treatments. Organizations such as Obesity Canada, the European Association for the Study of Obesity and the American Heart Association highlight their effectiveness for: 

• Sustained weight loss and maintenance 
• Safe and efficient obesity management, especially for high-risk individuals 
• Supporting long-term adherence in behavioral and multidisciplinary treatment programs 

Supported by clinical evidence, meal replacements are a proven, effective and accessible tool for obesity management.

While GLP-1 medications become increasingly popular, studies have found that weight regain is common after discontinuation. Sustainable habits like balanced nutrition, physical activity and lifestyle changes are key to long-term results. 

Meal replacements can support this strategy. They help address nutrient needs and support adherence to calorie reduction while minimizing the risk of nutrient deficiencies often associated with GLP-1 medications.

Not all meal replacements are created equal, and the quality of the product plays a crucial role in its effectiveness. In 2020, independent researchers examined the safety and efficacy of Herbalife® high-protein meal replacements for weight management. While the study was funded by the company, Herbalife had no involvement in the study’s execution, data analysis or manuscript preparation. 

The meta-analysis reviewed randomized controlled trials of Herbalife® high-protein products published in peer-reviewed journals up until July 2019. The researchers combined data from nine studies involving 934 participants – 463 in treatment groups and 471 in control groups. The results showed that participants using Herbalife® high-protein products saw significantly greater reductions in body weight, body mass index (BMI) and fat mass compared to those on control diets.

In summary, these studies show that meal replacement shakes work better than self-directed weight-loss attempts. While popular diet trends might work for short-term weight loss, in the long run, adherence will be an issue. 

If you’re looking to achieve and maintain a healthy body weight over the long-term with a partial meal replacement diet, it’s important to pair it with balanced nutrition and a healthy, active lifestyle. Social support also goes a long way, and it can be helpful to find a motivating community to help with your program. 

Ready to get started? Explore Herbalife's meal replacement products and begin your weight-loss journey today.

Dr. David Heber is the chairman of the Herbalife Nutrition Institute (HNI) and professor emeritus at UCLA’s David Geffen School of Medicine,* where he founded the Center for Human Nutrition. A board-certified specialist in internal medicine, endocrinology and metabolism, Dr. Heber is an expert in obesity treatment, cancer nutrition and dietary supplements. He has authored over 240 scientific papers and several books for the public, including “What Color Is Your Diet?” and “The L.A. Shape Diet.” 

*The University of California does not endorse specific products or services as a matter of policy.