Protein shakes provide essential nutrients to your body.
When you consume sufficient amounts of protein, metabolism improves and you’ll feel fuller, longer.
One way you can easily add extra protein to your diet is by drinking protein shakes; a proven means to promote weight loss.
What are Protein Shakes?
In its most basic form, a protein shake is simply protein powder mixed with water, but you can also add other ingredients.
One great thing about protein shakes is that they are easy to make and convenient to add to your diet, which is especially important if you don’t have regular access to other high-protein foods that are of high quality.
While you may not need protein shakes to reach your body’s daily protein requirements, they can be helpful for individuals who have a reason for increasing the amount of protein they consume, such as a medical condition.
There are both powdered protein options and ready-made liquid protein shakes on the market.
Protein powder comes in several varieties. Here are the most popular varieties:
- Brown Rice Protein: Rice powder is plant based and a good option for people who need to avoid protein powders that contain dairy. Rice powder is also easy to digest and hypoallergenic. (1) (2)
- Soy Protein: Soy protein is plant based and contains soy isoflavones, which have been shown to have some healthy benefits. Soy protein contains essential amino acids your body needs. (3) (4)
- Whey Protein: Whey protein is derived from dairy products. It contains nine essential amino acids, so it is considered a complete protein. (5)
- Casein Protein: Casein protein is dairy-based and absorbs more slowly than whey protein. (6)
- Pea Protein: Pea-protein is plant-based and contains essential amino acids that help support a healthy digestive system. (7)
- Hemp Protein: Hemp protein is plant-based and contains magnesium, which is a necessary nutrient. Hemp protein is also a good option for people who are lactose intolerant. (8)
Depending on the brand of protein powder you buy, you may find a blend of different types of protein; manufacturers sometimes do this because the proteins contain amino acids that complement one another.
Takeaway: Protein shakes can be purchased ready-made or mixed at home using protein powders. There are several different protein powders available so that you can choose the one that is best for you.
How Many Protein Shakes Should I Drink?
At most, your body can only use 0.9 grams of protein per pound of body weight, so it isn’t necessary to add an enormous amount of protein to your diet. Adding one protein shake per day is probably a good start. (9)
Some experts recommend replacing breakfast with a protein shake to reduce calorie intake and boost your metabolism. (10)
There are all kinds of different recipes for protein shakes. People often add ice and fruit to make a refreshing, delicious drink.
Drinking protein shakes made with whey may cause some uncomfortable gastrointestinal side effects if you are lactose intolerant. However, if that’s the case, switching to a plant-based protein should alleviate the problem.
Are There Side Effects to Protein Shakes?
Research has never proven that high protein diets are of any risk to the kidneys of healthy people. But, in those who have kidney problems, a low protein diet can be better. (12)
One study showed that doubling your protein intake leads to a loss of fat.
The study divided people into three groups: One group tripled their protein, one doubled their protein, and one ate the recommended dietary allowance (RDA) of protein.
The results of the study showed that the group that doubled their protein lost the most fat while the group that ate the recommended amount of protein lost the least. (16)
You can determine your RDA of protein by multiplying your body weight in pounds by 0.36. The resulting number is the RDA of protein in grams. (17)
Takeaway: Adding one protein shake per day to your diet can help you lose fat without harming your kidneys or bones. If you’re lactose intolerant, be sure to choose a plant-based protein to avoid gastrointestinal problems.
Will Protein Shakes Boost My Metabolism?
Your body has to burn more calories so it can digest protein than it does to digest carbs or fat, which can lead to weight loss. (20)
Eating more protein can help you to build muscle, especially if you participate in strength training. (23)
When you add muscle mass to your body, your body burns more calories even when you’re resting because muscle burns more calories than fat. (24)
One study involving obese participants showed that those who consumed protein shakes with 200 grams of extra protein per week gained 2.8 more pounds of muscle mass than those who drank shakes with no added protein. (25)
Takeaway: Adding protein shakes to your diet can help your body to burn more calories for two reasons: 1) Protein takes more calories to digest; 2) Protein helps build muscle and muscle burn more calories than fat.
Can Protein Shakes You Lose Belly Fat and Weight?
One study divided 40 men into two groups. Both consumed low-calorie diets, but one group received more protein than the other.
The results of the study showed that the higher protein group lost more fat, with an overall weight loss of 10.5 pounds, which was about 2.5 more than the low-protein group. (28)
Another study looked at various diets and compared their results. The participants who ate more protein lost around 31 pounds in 3 months, which was about 23% more weight than those following other diet plans. (29)
A separate study divided 30 overweight people into two groups. Both ate the same number of calories per day.
One ate a diet centered on carbs with only 15% of the calories coming from protein. The other ate a diet that consisted of 35% protein, including protein shakes made with whey protein.
At the end of the study, the group eating more protein lost between 5 and 7 pounds while the other group lost only 1 or 2. What’s more, the higher protein group shed mostly fat, especially in the belly. (30)
Takeaway: Increasing the protein in your diet by drinking protein shakes can help you lose weight, especially fat that collects around the belly.
Will Protein Shakes Help Me Feel Less Hungry?
In one study, men who had protein at breakfast ate an average of 112 fewer calories at a buffet luncheon and 400 less in the subsequent 24-hour period. (34)
Since eating protein will help you feel more full, you’ll automatically find yourself reaching for snacks less often, helping you to eat fewer calories throughout the day. (35)
In fact, one study of overweight men showed that those who upped their protein intake to 25% of their daily calories reduced their cravings by up to 60% and cut late-night snack consumption in half. (36)
Another study of athletes who were participating in resistance training showed that when they drank protein shakes containing whey protein, they rated their hunger at 50%-65% lower than without the protein shakes. (37)
Takeaway: Protein shakes can help you feel less hungry so that you reach for snacks less often and eat less at regular meals.
Can Protein Shakes Help Me Maintain Weight Loss?
If you’ve already been successful at losing weight, adding protein shakes to your diet could help you keep it off.
One study concluded that people on high-protein diets were able to lose more weight than those on low-carb or low-fat diets. They were also more successful at maintaining the weight loss.
Those who ate high-protein diets only gained back about 9% of the weight lost while those on lower protein diets gained back 23%. (38)
Another study looked at the effects of five different diets on weight loss and maintenance over a six month period. Two of the diets were high-protein diets, and they were the diets most successful for preventing weight gain.
Those participants on the high-protein diets regained less than 2 pounds while participants on the other three diets re-gained between four and six pounds. (39)
In another study, participants took 30 grams of a protein supplement, which lead to a reduction in waist size and regained less weight than the control group.
This indicates that it isn’t necessary to consume large amounts of protein to promote weight loss. And, since you want to avoid adding excess calories, one protein shake per day should be sufficient to help you meet your weight loss and maintenance goals. (40)
Takeaway: Protein shakes can help you avoid regaining the weight you’ve already lost. Just be sure not to add extra calories to your overall caloric intake for the day.
Can Protein Shakes Help Boost Metabolism and Build Muscle?
A lot of diets aimed at losing weight can cause muscle loss. Since we already know that muscle burns more calories than fat, thus boosting your metabolism, losing muscle can make it easier for your body to regain weight when you stop following the diet.
The good news is that if you continue with consuming a higher level of protein and participate in strength training, you can prevent muscle loss and keep your metabolism running at a higher rate. (41) (42)
A review of 25 studies showed that whey protein increases muscle protein synthesis, which is the process by which the body rebuilds muscle tissue. (43)
In fact, there is evidence that higher protein intake can make your body up to 350% more effective at maintaining muscle mass. (44)
Takeaway: Increasing your protein intake with protein shakes while you follow a weight loss diet can help your metabolism running at a higher rate and prevent the loss of muscle mass, especially if you combine your diet with a strength training program.
What Is the Best Kind of Protein to Use?
The body absorbs whey protein faster than casein, so whey helps you fill up faster. (45)
Also, researchers don’t all agree on which type of protein is best for weight loss and muscle maintenance.
In one study, whey protein was shown to increase weight loss by about 5 pounds more than soy protein. (46)
There are other factors to consider as well.
If you’re lactose intolerant, you may want to avoid dairy-based proteins like whey.
If you’re following a vegan diet, you’ll want to choose a plant-based protein.
You may also want to pay attention to the essential amino acids that your protein shake provides. However, if you’re also getting protein from other sources, this probably isn’t an issue.
Takeaway: While some studies show that whey is the best source, the evidence isn’t conclusive. Choose the protein powder that works best for you.
The Final Word on Protein Shakes
In general, people don’t have trouble getting enough protein in their diets without protein shakes.
Looking to lose weight? Shakes are an easy and safe (not to mention tasty!) way to get some extra protein.
Protein shakes not only help you lose weight, but boost metabolism, maintain muscle mass, and help keep the weight off.
Summer Banks, Director of Content at Dietspotlight, has researched over 5000 weight-loss programs, pills, shakes and diet plans. Previously, she managed 15 supplement brands, worked with doctors specializing in weight loss and completed coursework in nutrition at Stanford University. full bio.