You’ve been hitting the gym consistently, lifting heavy, and following a program featuring progressive overload. But after a few months, you notice that your T-shirts aren’t filling out how you’d like, and you’re struggling to build muscle. Breaking down your muscles in the gym is only part of the equation — you need to build them back up by eating enough calories and protein.
Sometimes, getting everything you need through your diet alone is challenging, and supplements can come in handy. Are you looking to build muscle and bulk up overall? Or are you trying to build lean muscle mass while maintaining your body weight or cutting some body fat? The answer will lead you to the right supplement.
Here, we’ll dive into two powerful supplements to support your muscle-building journey: mass gainer and whey protein. You’ll learn the differences, similarities, and the pros and cons of both. You’ll finally be able to choose the right one to your repertoire to help you get the type of gains you’re working for. Mass gainer versus whey protein — let’s get into it.
Editor’s Note: The content on BarBend is meant to be informative in nature, but it should not be taken as medical advice. When starting a new training regimen and/or diet, it is always a good idea to consult with a trusted medical professional. We are not a medical resource. The opinions and articles on this site are not intended for use as diagnosis, prevention, and/or treatment of health problems. They are not substitutes for consulting a qualified medical professional.
- Key Differences
- Key Similarities
- What Is Mass Gainer?
- The Benefits of Mass Gainer
- The Cons of the Mass Gainer
- How to Use Mass Gainer
- What Is Whey Protein?
- The Benefits of Whey Protein
- The Cons of Whey Protein
- How to Use Whey Protein
- Frequently Asked Questions
Mass gainer and whey protein are both dietary supplements that can help you gain muscle when paired with resistance training. Here’s where they differ.
- Calorie Content: Mass gainer is high in calories, ranging from 700 to over 1000 per serving. Whey protein is much lower, ranging from 120 to 150 calories per serving.
- Macronutrient Content: Mass gainer contains protein, a high amount of carbohydrates, and some fat. Whey protein offers concentrated protein with minimal carbs and fat.
- Weight Gain Vs. Muscle Gain: The high caloric content of mass gainer makes it useful to gain weight. The lower caloric but high protein content of whey protein makes it helpful in gaining muscle while maintaining or losing body fat.
- Meal Replacement Vs. Protein Supplement: Mass gainer contains a high amount of calories, carbs, and fat, so you could use it with a meal replacement or as an additional meal. Whey protein is a protein supplement and does not constitute a complete meal.
Choosing the right supplement for your specific goal is important — but here is where they overlap.
- Helps Build Muscle: Mass gainer and whey protein can both be part of your nutritional strategy for building muscle when combined with resistance training. They both contain the protein and amino acids you need for muscle protein synthesis.
- May Help Increase Strength: Both supplements may help you increase strength over time when you put in quality work at the gym.
- Aids Muscle Recovery: You can have mass gainer or whey protein in a post-workout shake to boost your muscle recovery.
- Convenient Nutrient Boost: If you struggle to get enough protein from your diet to support your workouts, both mass gainer and whey protein are convenient ways to get extra nutrients in supplement form.
Mass gainers, sometimes called weight gainers, are powdered dietary supplements high in calories, protein, carbohydrates, and fat. Their purpose is to help you gain weight by taking a convenient supplement. When you’re trying to pack on mass, it may be challenging to reach your caloric intake needs through food alone due to finances, time, or your biological makeup.
They may also contain other ingredients like creatine that can aid muscle building when combined with resistance training.
Mass gainer supplements purport to do what they say in the name: help you gain mass. This can benefit people struggling to gain weight and bodybuilders in a bulking phase. Mass gainer may also boost your performance — it can help you build muscle and give you more energy for your workouts.
May Help “Hard Gainers”
Weight gain and weight loss may seem simple, but it’s not always straightforward. Theoretically, eating more calories than you expend will cause weight gain, and eating fewer calories than you burn will cause weight loss. However, many people’s bodies don’t react accordingly due to hormonal or metabolic differences.
The term “hard gainers” refers to people who have difficulty gaining weight. Their bodies seem to sit at a lower weight naturally. They may have faster metabolisms. If they are athletes or otherwise highly active, hard gainers may burn so much energy every day that they struggle to keep weight on no matter how much they eat.
[Read More: The Definitive Guide to Bodybuilding Meal Prep]
Regardless of the why, mass gainer supplements may benefit people who want to gain weight and have difficulty doing so through their diet alone. Some mass gainer brands contain up to 1,250 calories in a single serving, and it’s quick to throw into a shake and consume.
Convenient for Bulking
Some bodybuilders going through a bulking phase may benefit from taking a mass gainer. If you’re aiming for a high-calorie intake, buying and eating enough food can get time-consuming and expensive. Eating high volumes of food can also cause digestive or emotional discomfort. A high-calorie scoop of mass gainer can help you get closer to your goal.
Other bodybuilders may not opt for a mass gainer supplement if they gain weight easily and are only looking to pack on lean muscle.
May Help Build Muscle
You must exercise regularly and eat enough calories and protein to build muscle. Building muscle isn’t the primary aim of mass gainer, but it can help you get closer to your protein intake goals.
When you lift weights, muscle protein breakdown occurs. After lifting weights, consuming dietary protein through food or supplements assists muscle protein synthesis. Protein helps repair your muscle tissue, leading to skeletal muscle growth and recovery. (1)(2)
Some mass gainer supplements contain creatine, which can further help. Creatine is an amino acid that can lead to better muscular contractions during short-duration, highly intense activities like weightlifting. As a dietary supplement, creatine has over 50 years of research showing that it may help increase lean muscle mass when paired with weightlifting. (3)
Mass gainers may also contain beta-hydroxy beta-methylbutyrate (HMB). HMB comes from leucine. Leucine is a precursor for muscle protein synthesis. Research on HMB supplements suggests they may help increase muscle mass and strength when paired with resistance training. (4)
May Increase Energy Levels
Mass gainer is typically high in carbohydrates. After consuming carbs, your body stores them as glucose, which it can use for energy. Extra glucose gets stored as glycogen, which your body can use for high-intensity training like weightlifting or sprint workouts. Consuming enough carbs can help keep your glycogen stores full, energizing you for your workouts. (5)
Mass gainer supplements often contain maltodextrin, a simple carb with a high glycemic index. Maltodextrin may increase your energy levels and help with weight gain due to its ability to spike your blood sugar. (6)
Taking a mass gainer is a convenient way to gain weight, but you can’t control what kind of weight you gain. You may gain muscle if you’re training, but you may gain unwanted fat along with it. It may also trigger gastrointestinal issues and be high in sugar and other additives.
May Cause Unwanted Fat Gain
Consuming excess calories to help you gain muscle mass may come with some unwanted fat as a byproduct. However, this may not bother you if you are trying to bulk up overall or gain weight for medical reasons.
May Cause Gastrointestinal Issues
Most dietary supplements come along with potential side effects. Mass gainers may cause gastrointestinal distress. Symptoms may include bloating, gas, stomach pain, nausea, diarrhea, or constipation.
If you know you are sensitive to lactose, you can opt for a lactose-free mass gainer supplement.
May Be High in Sugar and Additives
Mass gainers contain additives, including sugar. If you are mindful of your sugar intake for metabolic reasons, be sure to take note of the sugar content.
Dietary supplements, including mass gainers, don’t need to be approved by the U.S. Food and Drug Administration (FDA) to be sold. They may contain chemicals, additives, banned ingredients, and extra undisclosed ingredients. (7)
It’s best to consult with a medical professional before adding a new supplement to your diet. Check if it will interact with any conditions you have or medications you take.
Once you are cleared, start slowly. Begin with the recommended serving size on the label or less.
Mix one serving with water, milk, or other ingredients you’d like to add. Shake or blend it up and enjoy.
Track your overall caloric intake with your mass gainer, and weigh yourself weekly. It’s helpful to weigh yourself wearing the same clothing at the same time of day. Track your weight over a few weeks and notice if you can gain weight. It could take some time to see progress.
Whey protein is a dietary supplement gymgoers may use to help them build muscle. Whey is a substance that comes from milk during the manufacturing of cheese. After removing the water and some lactose from whey, mainly protein remains. It then becomes whey protein powder. (8) Whey is high in protein but low in calories, fat, and carbohydrates.
There are three main types of whey protein. Whey protein concentrate is the most popular and affordable. Whey isolate has most of its lactose, carbs, and fat removed. Whey protein hydrolysate is pure protein — it’s pre-digested and already broken down into amino acids. It contains almost no lactose. (8)
Whey protein is considered a high-quality, complete protein source. A complete protein source contains all nine of your essential amino acids and the 11 non-essential amino acids. “High quality” refers to its ability to be quickly digested and absorbed. (8)
Whey protein supplements are a convenient way to increase your daily protein intake without adding extra calories, carbs, and fat. Incorporating whey protein into a resistance training program may help you build muscle, lose fat, and recover from workouts. It may also lower your blood pressure.
May Help Build Muscle
When paired with a resistance training program, research has consistently shown that supplementing with whey protein can help increase muscle protein synthesis in people of all ages and genders. (9)
While how much protein you get is crucial to building muscle, research shows that the quality of your protein content matters regarding supplements. Whey protein is considered one of the highest-quality sources. It contains all amino acids necessary for muscle protein synthesis and is readily available for muscle gain. (9)
[Read More: The Complete Guide to Pre-Workout Supplements]
Whey is also high in leucine, a precursor for muscle protein synthesis. You still need all 22 amino acids present for hypertrophy to occur, but having more leucine may help. (10)
May Support Fat Loss
Mass gainer helps you gain weight, but whey protein can help you lose body fat while building or maintaining muscle.
Protein is known to be the most satiating macronutrient, and high-protein diets can help you feel fuller for longer. If you’re decreasing your calories or portions to lose body fat, consuming whey protein can help you stay on track. High-protein diets also increase thermogenesis — they need more energy to digest. This can slightly increase your total daily energy expenditure (TDEE). (11)
Consuming whey protein during fat loss helps you maintain muscle mass. You can theoretically lose weight by consuming fewer calories than your body needs. But having enough protein can ensure that you lose body fat while maintaining muscle. (11)(12)
[Read More: How to Burn Fat for Weight Loss and More Definition]
May Improve Muscle Recovery
After training hard, consuming whey protein can improve your muscle recovery. Protein, in general, is needed to repair muscle tissue and cell damage while stimulating hormonal and metabolic activity, leading to muscle growth. (13)
Whey protein has anti-inflammatory and antioxidant properties that can further boost your recovery. It’s high in the amino acid cysteine. Your body converts cysteine to glutathione, which helps repair cell damage after a workout. (14)
May Lower Blood Pressure
If you have high blood pressure (hypertension), research shows that whey protein may help to lower it and boost your cardiac health. This may be due to whey protein coming from milk. Some peptides in milk protein called lactokinins can help to lower blood pressure. (16)(17)
Another theory is that whey protein helps to create nitric oxide in your body. Whey protein contains all the essential amino acids, including L-arginine, a precursor for nitric oxide. Nitric oxide increases vasodilation, the widening and relaxing of your blood vessels. More vasodilation allows for better blood flow and lower blood pressure. (18)
Although whey protein is high-quality, it has some drawbacks for people with particular food preferences and sensitivities. It’s not a dairy-free product. Whey may cause stomach discomfort, and it’s lower in other nutrients.
Whey comes from cow’s milk, so it’s not a product that vegans can use. As an alternative, soy protein powder is plant-based and may have similar benefits to whey.
May Cause Gastrointestinal Distress
Whey protein may have some unpleasant gastrointestinal side effects. It’s known to cause gas, bloating, and stomach discomfort. If you are sensitive to lactose, that could be the trigger.
Other forms of whey protein have less lactose than whey protein concentrate like whey protein isolate and whey protein hydrolysate, but they’re not entirely lactose-free.
Lower in Other Nutrients
Mass gainer is high in carbohydrates, fats, and (potentially) other nutrients. One of the benefits of whey protein is that it is pure protein — but if you want your supplement to have other nutrients, this could be a drawback for you.
Consult with a doctor or healthcare provider before trying a new supplement.
If you’re good to go, follow the serving size on the label, which is generally one scoop. Mix one scoop of whey protein with water, milk, or another liquid and shake or blend. Add other ingredients like ice cubes or frozen fruit to make a thicker protein shake.
Research suggests that having a 20 to 25-gram serving of whey protein after resistance training may help increase muscle protein synthesis. (19)
Cut or Bulk Up?
While getting the bulk of your calories and nutrients from whole foods is best, adding a supplement can help support a fitness goal. Mass gainer and whey protein both contain protein and can help you build muscle and recover from training.
Mass gainer is high in calories, carbs, and fat. It’s useful for people who want to gain weight in addition to muscle. Whey protein is mainly protein and low in carbs, fat, and calories. It’s a better choice if you’re looking to build lean muscle while maintaining your weight or losing body fat.
While these supplements can help you in the kitchen, a significant part of building muscle is lifting weights — so shake up your drink, but don’t skip leg day.
Here are the answers to some common questions on whey protein versus mass gainer.
Should I take whey protein and mass gainer?
If you’re trying to gain weight and build muscle, it may be beneficial to take both. Mass gainer already contains protein, but adding whey can help you boost your daily protein intake.
What is the difference between whey protein and mass gainer?
Whey protein is high in protein and low in calories, carbs, and fat. It’s a good supplement to help you build muscle while maintaining weight or losing body fat. Mass gainer can have over 1000 calories per serving and is high in carbs and fat. It’s better for people struggling to keep weight on or bulking when you want to add a lot of mass.
Which is better for pregnant people, whey protein or mass gainer?
If you’re pregnant, it’s best to consult a doctor before adding any supplement. Mass gainer may be beneficial if a pregnant person needs or wants to gain weight. Whey protein is better if they are just trying to increase their protein intake.
- Carbone JW, Pasiakos SM. Dietary Protein and Muscle Mass: Translating Science to Application and Health Benefit. Nutrients. 2019 May 22;11(5):1136.
- Camera DM. Evaluating the Effects of Increased Protein Intake on Muscle Strength, Hypertrophy and Power Adaptations with Concurrent Training: A Narrative Review. Sports Med. 2022 Mar;52(3):441-461.
- Wu SH, Chen KL, Hsu C, Chen HC, Chen JY, Yu SY, Shiu YJ. Creatine Supplementation for Muscle Growth: A Scoping Review of Randomized Clinical Trials from 2012 to 2021. Nutrients. 2022 Mar 16;14(6):1255.
- Portal S, Eliakim A, Nemet D, Halevy O, Zadik Z. Effect of HMB supplementation on body composition, fitness, hormonal profile and muscle damage indices. J Pediatr Endocrinol Metab. 2010 Jul;23(7):641-50.
- Kerksick CM, Arent S, Schoenfeld BJ, Stout JR, Campbell B, Wilborn CD, Taylor L, Kalman D, Smith-Ryan AE, Kreider RB, Willoughby D, Arciero PJ, VanDusseldorp TA, Ormsbee MJ, Wildman R, Greenwood M, Ziegenfuss TN, Aragon AA, Antonio J. International society of sports nutrition position stand: nutrient timing. J Int Soc Sports Nutr. 2017 Aug 29;14:33.
- Hofman DL, van Buul VJ, Brouns FJ. Nutrition, Health, and Regulatory Aspects of Digestible Maltodextrins. Crit Rev Food Sci Nutr. 2016 Sep 9;56(12):2091-100.
- Ronis MJJ, Pedersen KB, Watt J. Adverse Effects of Nutraceuticals and Dietary Supplements. Annu Rev Pharmacol Toxicol. 2018 Jan 6;58:583-601.
- Hoffman JR, Falvo MJ. Protein – Which is Best? J Sports Sci Med. 2004 Sep 1;3(3):118-30.
- Hulmi, J.J., Lockwood, C.M. & Stout, J.R. Effect of protein/essential amino acids and resistance training on skeletal muscle hypertrophy: A case for whey protein. Nutr Metab (Lond) 7, 51 (2010).
- Wolfe RR. Branched-chain amino acids and muscle protein synthesis in humans: myth or reality? J Int Soc Sports Nutr. 2017 Aug 22;14:30.
- Paddon-Jones D, Westman E, Mattes RD, Wolfe RR, Astrup A, Westerterp-Plantenga M. Protein, weight management, and satiety. Am J Clin Nutr. 2008 May;87(5):1558S-1561S.
- Frestedt JL, Zenk JL, Kuskowski MA, Ward LS, Bastian ED. A whey-protein supplement increases fat loss and spares lean muscle in obese subjects: a randomized human clinical study. Nutr Metab (Lond). 2008 Mar 27;5:8.
- Urso ML. Anti-inflammatory interventions and skeletal muscle injury: benefit or detriment? J Appl Physiol (1985). 2013 Sep;115(6):920-8.
- Marshall K. Therapeutic applications of whey protein. Altern Med Rev. 2004 Jun;9(2):136-56.
- Urso ML. Anti-inflammatory interventions and skeletal muscle injury: benefit or detriment? J Appl Physiol (1985). 2013 Sep;115(6):920-8.
- Pal S, Ellis V. The chronic effects of whey proteins on blood pressure, vascular function, and inflammatory markers in overweight individuals. Obesity (Silver Spring). 2010 Jul;18(7):1354-9.
- Yamamoto N, Takano T. Antihypertensive peptides derived from milk proteins. Nahrung. 1999 Jun;43(3):159-64.
- Houston M, Hays L. Acute effects of an oral nitric oxide supplement on blood pressure, endothelial function, and vascular compliance in hypertensive patients. J Clin Hypertens (Greenwich). 2014 Jul;16(7):524-9.
- West DWD, Abou Sawan S, Mazzulla M, Williamson E, Moore DR. Whey Protein Supplementation Enhances Whole Body Protein Metabolism and Performance Recovery after Resistance Exercise: A Double-Blind Crossover Study. Nutrients. 2017 Jul 11;9(7):735.
Featured Image: Room 76 / Shutterstock