Can Protein Shakes Make Me Put on Weight? The Truth Behind the Myth

October 23, 2025 •

4 min read

According to nutritionists, weight gain is primarily determined by your total caloric intake, not one single food or supplement. This critical fact sheds light on the common question: can protein shakes make me put on weight, and if so, is it muscle or fat? The answer lies in how these shakes are incorporated into your overall diet and activity level.

Quick Summary

Weight gain from protein shakes occurs when they contribute to a caloric surplus. The shakes themselves, or high-calorie additions, can cause you to consume more energy than you burn, resulting in weight gain.

Key Points

Caloric Surplus is Key: Protein shakes cause weight gain only when they contribute to a higher overall caloric intake than your body burns.
Fat vs. Muscle Gain: Combining protein shakes with resistance training promotes muscle gain, whereas consuming them without exercise can lead to fat gain from excess calories.
Ingredient Matters: The calorie count of a protein shake is heavily influenced by additions like milk, nut butters, and fruits, not just the powder itself.
Mass Gainers are Different: Some products, like 'mass gainers', are specifically formulated with high calories to promote weight gain and are not standard protein supplements.
Use Strategically: Protein shakes can be used for both weight gain and loss depending on the total calorie goal. For weight loss, focus on low-calorie mixes; for gain, incorporate high-calorie ingredients.
Avoid Excesses: Long-term excessive protein intake can be harmful and may strain the kidneys, especially when consumed beyond recommended levels.

The Calorie Balance: The Real Driver of Weight Changes

At its core, weight management is a simple equation of energy in versus energy out. You gain weight when you consistently consume more calories than your body burns, a state known as a caloric surplus. Conversely, you lose weight in a caloric deficit. Protein shakes are not inherently fattening; they are simply a source of calories, just like any other food or drink. The potential for weight gain depends entirely on whether those shake calories push your total daily intake beyond your body's energy needs.

Protein for Muscle Gain vs. Fat Gain

The composition of the weight you gain is influenced by your physical activity. If you combine a protein-rich diet with a consistent resistance training program, the extra calories, particularly from protein, will be directed towards building and repairing muscle tissue. However, if you consume high-calorie protein shakes without exercising, the excess calories will be stored by the body as fat. This distinction is crucial for understanding how to use protein shakes effectively for your specific body composition goals.

The Role of Ingredients and Shake Composition

Not all protein shakes are created equal. The most significant factor influencing a shake's weight gain potential is not just the protein powder itself, but what you mix with it. A standard scoop of protein powder mixed with water is a relatively low-calorie drink, often around 120-150 calories. However, the additional ingredients can dramatically increase the total calories.

High-Calorie Additions for Weight Gain

For those intentionally trying to gain weight or build muscle, adding extra ingredients is key. Here are some examples of high-calorie additions:

Whole Milk or Dairy-Free Alternatives: Using whole milk instead of water adds significant calories, fats, and protein.
Nut Butters: A tablespoon or two of peanut, almond, or cashew butter provides healthy fats and a substantial calorie boost.
Oats: Adding rolled oats or oat flour thickens the shake and increases carbohydrate content for extra energy.
Avocado: A creamy, calorie-dense fruit packed with healthy fats.
Fruits: Bananas and other fruits can add natural sugars, vitamins, and extra calories.
Mass Gainer Supplements: These are specifically engineered products with a high ratio of carbohydrates and fats to protein, designed for significant calorie intake.

Protein Shake Comparison: Gain vs. Loss


Feature	Weight Gain Shake	Weight Loss Shake
Powder Type	Mass Gainer or Standard Whey/Casein	Standard Whey, Casein, or Plant-Based
Liquid Base	Whole Milk, Full-Fat Yogurt, or Juice	Water or Unsweetened Almond Milk
Primary Additions	Nut Butters, Oats, Bananas, Dates	Leafy Greens, Berries, Chia Seeds
Calorie Count	Typically 500+ calories	Typically <200 calories
Goal	Caloric Surplus for Muscle Growth	Caloric Deficit for Fat Loss
Key Macronutrient	Balanced Protein and Carbs	High Protein, Low Calorie

Using Protein Shakes Strategically for Your Goals

To control whether your protein shake leads to weight gain or weight loss, strategic use is necessary. If your goal is to lose weight, a protein shake can help manage hunger and preserve muscle mass while on a calorie-restricted diet. A simple protein shake with water or unsweetened milk can be a satisfying, low-calorie snack or meal replacement. However, be cautious not to replace nutrient-dense whole foods with shakes over the long term.

For those aiming for weight gain or muscle building, using shakes to increase daily caloric intake is a practical approach. Timing can be important here, with many fitness enthusiasts consuming a shake post-workout to help with muscle recovery and growth. The added convenience makes it easier to hit higher calorie targets, especially for individuals with smaller appetites.

Potential Risks of Excessive Protein

While protein shakes are a safe and effective dietary tool for most people, consuming excessively high amounts of protein over the long term can pose risks, particularly to kidney function. The average adult requires around 0.8 grams of protein per kilogram of body weight, with active individuals needing more. Exceeding 2.0–2.5 grams per kilogram for extended periods can place extra strain on the kidneys and potentially lead to other health issues. A balanced approach that incorporates whole food sources of protein is always recommended.

Conclusion: Mind Your Calories to Manage Your Weight

Ultimately, the question, "Can protein shakes make me put on weight?" has a clear answer: yes, they can, but only by contributing to a caloric surplus. The outcome—whether you gain fat or muscle—is determined by your overall diet and exercise routine. By understanding the calorie content of your shakes and how they fit into your daily energy balance, you can effectively use them to reach your weight management goals, whether that's bulking up or slimming down. The key is mindful consumption and ensuring that supplements complement, rather than replace, a healthy diet rich in whole foods.

For additional scientific insights on nutrition and protein intake, consult reputable health organizations like the National Institutes of Health. (https://pmc.ncbi.nlm.nih.gov/articles/PMC7781151/)

Frequently Asked Questions

Yes, if the calories from the shakes, combined with your regular food intake, create a caloric surplus, you will gain weight. Without exercise, this weight is likely to be stored as fat, not muscle.

The calorie content varies widely depending on the ingredients. A standard scoop of protein powder with water is usually 120-150 calories, but adding milk, nut butters, and fruit can easily increase it to 500+ calories.

Mass gainer supplements are designed for high calorie intake to promote weight gain. While they are formulated to support muscle growth, consuming them without a sufficient exercise regimen can certainly lead to fat gain from the excess calories.

For weight loss, use protein shakes to help maintain a calorie deficit. Choose low-calorie liquids like water or unsweetened almond milk and use them as a satiating snack or occasional meal replacement to control overall calorie intake.

Yes. Gaining muscle mass requires a combination of adequate protein intake and resistance training. Without exercise, the excess calories from protein shakes are more likely to be stored as body fat.

For most healthy individuals, moderate protein intake is safe. However, long-term, excessive protein consumption (typically over 2.0 g/kg of body weight) can put additional strain on the kidneys, especially if you have a pre-existing condition.

No. While all provide protein, their calorie counts and composition differ. Mass gainers are high-calorie, while standard whey or plant-based powders are lower in calories. The key is the overall calorie balance, regardless of the powder type.