Will Protein Powder Make You Gain Weight? Here’s What a Dietitian Says

Protein is an essential nutrient that helps our body build muscle, regulate appetite, and plays a role in our hormones, skin, hair and more. Consuming a protein supplement, such as protein powder, will not automatically make you gain weight. It all depends on how much your consume and your everyday diet.

While most Americans eat enough protein (more on that later), optimal amounts can be challenging to get, especially if you’re on the go. 

Many people turn to protein powder to balance out smoothies, or make sure they can replenish their muscles after a tough workout. But is your protein powder taking a toll on your weight goals? Protein powder isn’t going to magically change the number on the scale, but there are some things to keep in mind if you want to add more protein to help you lose or gain weight.

Does protein powder cause weight gain? 

“You can lose weight, gain weight, or have no changes in your weight once you start adding protein powder,” says Lainey Younkin, MS, RD, LDN, weight loss dietitian at Lainey Younkin Nutrition. “That's because whether you lose or gain weight has to do with total calorie consumption, not just protein.”  

If you eat too many calories over time, you gain weight. It doesn’t matter if the calories come from peanut butter, protein powder, or pasta. Protein isn’t usually the culprit for weight gain since carbohydrates are easier to overeat (handfuls of candy or bowls of noodles) and fat has more calories per gram (9 vs. 4 for protein and carbs). 

Younkin also adds, “Protein is the most satiating macronutrient. When people eat more protein, especially in the morning, they tend to eat fewer total calories overall.” 

Not everyone wants to lose weight though. If you’re looking to build muscle, eating enough protein, along with strength training is key. Eating a higher-protein diet can help you gain weight and add lean muscle mass, according to research.  

Protein powder for weight loss 

A fair amount of studies have linked higher-protein diets to weight loss. That’s because protein keeps you full and satisfied and maintains muscle mass, which is key for your metabolism. You don’t necessarily need to add protein powder to your diet if you have weight-loss goals but it makes getting enough protein a little bit easier to do. Adding a smoothie or pancakes with protein powder can easily add protein to your day.  

According to Younkin, “protein powders and shakes usually have 20-30 grams of protein per serving and are a convenient and simple way to reach your protein goal each day.” 

Of course it’s not just about adding protein, you need to stay mindful of overall caloric intake. Lifestyle changes like getting enough sleep, reducing stress and moving your body all can help you lose weight too, but diet changes are the biggest lever you can pull when it comes to weight loss.  

When you add protein powder to your day makes a difference too. “I find protein powders and shakes to be most helpful when consumed at breakfast because people struggle the most with getting enough protein in the morning. Most people could benefit from 25-30 grams of protein at breakfast but don't realize that two eggs, for example, is only 12 grams of protein,” says Younkin.  

How much protein do I need? 

Protein needs vary based on sex, age, activity level and more. The RDA for protein is 0.8 g/kg of body weight, athletes need between 1-1.6 g/kg depending on how much exercise they are doing. The recommended range for protein is 10-35 percent of total calories in your diet. 

With the variety in recommendations, there isn’t a one-size-fits-all approach to protein. Younkin adds, "recent research suggests that higher protein intake closer to 1.2-1.6 g/kg or 30 percent of daily calories from protein is optimal for weight loss. This can be hard for some people to get from whole foods alone, especially if also trying to stay in a calorie deficit.” 

Since protein helps you stay satisfied, whether you are maintaining your weight or trying to lose weight, hitting the range of 1.2-1.6 g/kg, about 0.5-0.75 g/lb is a good target.  

If you want to add muscle and bulk up a range of 1.6-2 g/kg or 0.7-1g/lb might be better to aim for.   

You shouldn’t get all of your protein from a powder though. Whole food sources will deliver other nutrients. Think calcium from Greek yogurt and omega-3’s from salmon. Making sure to include a protein-rich food at every meal and snack will help you get enough throughout the day. Younkin recommends whole foods like chicken, turkey, fish, cottage cheese, ground beef, edamame, and eggs. The occasional protein shake or protein bar is nice to have when you need convenience and a protein boost on the go. 

Does type of protein powder matter? 

Just like you can choose what you add your protein powder to, there is a huge variety to the types of protein powder you can buy. What you choose to eat may depend on your needs and preferences, or just what your roommate left lying around in the pantry.  

Types of protein powder include:  

What happens if you drink a protein shake and don’t workout?

Protein shakes help your body build muscle, but you need to combine them with strength training. However, drinking them on rest days can still be a great way to recover and hit your protein goals.

Lisa Valente is a registered dietitian with over 15 years of experience and.a Masters Degree in Nutrition Communications from Tufts University. She loves talking about all things food, nutrition, and wellness and breaking down complex science into more digestible information you can actually use. Find her eating peanut butter by the spoonful, hiking in the mountains, or running around with her family.