In This Article
In This Article
Everyone knows that eating right and exercising are key to losing weight.
But sometimes eating a healthy and nutritious diet isn’t always practical. Many people lead busy lifestyles and don’t have time to prepare the right foods. This can hinder their attempts to lose weight.
Meal replacement shakes are a convenient option for helping you achieve your weight loss goals. They help keep you full and make sure you’re getting the important nutrients your body needs while minimizing calorie intake.
“Meal replacements—like shakes—provide a low-calorie alternative to a well-balanced meal. They are high in protein, low in glycemic index, and are nutrient-dense,” says our expert Dr. Rizza Mira.
Let’s see what research says about how meal replacement shakes work and why they’re so effective for weight loss.
A meal replacement shake is a pre-mixed drink designed to be a nutritional substitute for solid food. Meal replacement shakes contain most, if not all, the necessary nutrients you’d normally get from a meal.
Meal replacement products can also come in other forms, such as bars, soups, or powders.
They typically contain between 200-400 calories and a balance of proteins, fats, carbohydrates, and fiber that you find in a regular meal.
There are multiple ways in which meal replacement shakes help with weight loss.
Protein is much more effective at keeping you full and reducing your appetite than either carbs or fats. Eating more protein helps you feel fuller for longer, so you’re less likely to overeat.1
Protein increases levels of hormones that make you feel full such as cholecystokinin, while at the same time decreasing hormones that stimulate hunger, such as ghrelin.2 Controlling your appetite is important when trying to lose weight because weight loss tends to increase hunger levels.
Protein also helps maintain muscle mass, which keeps your metabolism higher and makes it easier to burn more calories at rest.2
“During weight loss, a diet high in protein also protects a person from losing his/her lean body mass so as to avoid malnutrition,” says Dr. Mira.
The glycemic index (GI) measures how fast a food raises your blood sugar levels. Foods with a high GI cause your blood sugar levels to quickly spike and crash shortly after.
When blood sugar levels fall too quickly, you tend to get hungry. This isn’t helpful if you’re trying to lose weight.
Meal replacement shakes are designed to have a low GI–in part due to their high protein levels. This means they cause a steady rise in blood sugar that doesn’t result in a crash, which helps control your appetite.2
Nutrient density is the amount of nutrients in a food in comparison to its calorie content.
Foods with a high nutrient density have a lot of vitamins and minerals yet are relatively low in calories. Examples of high nutrient-density foods include lean meats, fish and seafood, fruits and vegetables, nuts, and legumes.
Foods with a low nutrient density have a lot of calories and offer few nutrients. Think baked desserts, fruit juices, sodas, and cereal.
Meal replacement shakes are typically nutrient-dense, which means they’re a great source of vitamins and minerals without too many calories.
“Nutrient-dense foods are also antioxidant-rich. These help prevent other metabolic conditions like diabetes and metabolic syndrome,” says Dr. Mira.
Eating a diet high in nutrient-dense foods not only helps reduce hunger but changes the way hunger affects you. In a study, people switched from a low nutrient-density diet to a high one and reported feeling hungry less frequently and tolerating hunger better.3
Replacing one or more of your meals with a fulfilling meal replacement shake may change your relationship with food.
Instead of seeing food as a way to get rid of your hunger, you begin to see food as nourishment that helps keep your body healthy.
A four-year study of 100 obese patients conducted by the University of Ulm Obesity Center found that meal replacement products led to five times greater weight loss than calorie-restricted diets. The researchers concluded there were six main factors why meal replacement diets work so well for weight loss.4
Let’s take a closer look at each of these factors.
Meal replacements are much more convenient than regular meals.
You don’t have to decide what to eat. You don’t have to spend time grocery shopping. You don’t have to worry about preparing and cooking any food, and there’s no mess to clean up after.
These are some of the biggest barriers to losing weight.
Instead, you can have a nutritious, filling meal replacement shake ready within minutes.
Meal replacements help you ignore the impulse to eat unhealthy foods by making it easier to consume a healthy meal. They also help prevent you from eating too many calories by keeping you fuller for longer.
One of the most important ways meal replacements can help you lose weight is by making it easy to accurately track how many calories you’re eating.
Because you know exactly how many calories are in each serving, you’re better able to keep track of and limit your total calories for the day.
When you’re eating regular meals, it can often be hard to accurately estimate how many calories are in a food or a dish that you’ve prepared. This can lead to you underestimating the number of calories you’re actually eating, which can lead to weight gain.
Reducing your calorie consumption means eating less food.
However, this can make it hard to get all the nutrients your body requires to be healthy. One of the dangers of sudden weight loss is malnutrition—a lack of the necessary vitamins and minerals to keep the cells functioning.
Meal replacements are typically fortified with the essential vitamins and minerals your body needs. They help you avoid nutrient deficiencies.
Because meal replacements help people track calories, it encourages people to become more aware of their eating patterns.
By removing common barriers to weight loss, meal replacements make you more accountable when attempting to reach your weight loss goal. In other words, you can’t blame your unhealthy eating habits on a lack of time to prepare food or being too hungry. It all comes down to making the right choices with your health.
Meal replacements help establish a routine, which can greatly aid in weight loss.
Having a go-to meal you can consume at the same time every day helps prevent you from going long periods without eating and getting too hungry.
Yes, it does.
A large review published in 2019 looked at the effects of meal replacements in comparison to weight loss diets across 23 studies and 7,884 participants.
The researchers found that after one year, participants who used meal replacements lost an average of three pounds more than participants who followed a diet.5
They also found that those in the meal replacement group who received diet and behavioral counseling from professionals lost an additional two pounds in comparison to their dieting counterparts who received the same counseling.5 There is no substitute for a determined mind whose goal is toward sustainable weight loss.
Another review of six studies found that people using meal replacements lost five pounds more than people eating a low-calorie diet.
Those in the meal replacement group were also less likely to drop out of the study. This was because meal replacements make it easier to stick to a weight loss program.6
Meal replacement programs have also been shown to help you keep weight off after you lose it. When people reach their weight loss goals or finish their dieting, they often resort to their old eating habits and regain the weight.7
Meal replacements offer a great way to maintain your weight due to how convenient they are and how easy they make tracking calories.
If you’ve been struggling to lose weight because you just can’t stick to a weight loss plan, meal replacements could be the answer to your problems.
