Weight Gainers
Check out our best weight gain supplements. Whether you’re trying to increase strength and size, or struggling to gain weight, the most important thing is creating a calorie surplus — taking on more calories than you burn.
Shop Mass Gainers at Myprotein
A mass gainer is built for one purpose: getting enough calories and macros in when whole food alone isn't cutting it. Whether you're in a structured bulk or simply struggling to hit your daily intake, a weight gainer gives you a concentrated hit of protein and carbohydrates in a single serving — no prep, no guesswork. Protein contributes to the growth and maintenance of muscle mass1, and carbohydrates contribute to the recovery of normal muscle function after highly intensive and/or long-lasting physical exercise leading to muscle fatigue and the depletion of glycogen stores in skeletal muscle2.
Mass gainers aren't just about calories — the macro split matters. A well-formulated weight gainer supplement delivers a meaningful ratio of protein to carbs, so every serving is working hard for your training goals. From post-workout shakes to between-meal top-ups, these are practical tools for anyone who needs to eat more but finds it difficult to do so through food alone.
Who Mass Gainers Are For
Mass gainers are designed for anyone who struggles to consume enough calories and macronutrients to support their training. That includes hard gainers — people with fast metabolisms who find it difficult to put on size regardless of how much they eat — as well as athletes in heavy training blocks who have significantly elevated calorie needs that food alone rarely satisfies.
They're also a practical option for people with busy schedules who don't have the time to cook high-calorie meals multiple times a day. A weight gainer supplement fills the gap between what you're eating and what your body needs, without requiring hours in the kitchen. If you're training hard and the scales aren't moving, a mass gainer is worth considering.
When to Use Mass Gainers
Timing a weight gainer depends on where the biggest gap in your daily intake falls. Many people use them post-workout, when the body needs both protein and carbohydrates — protein contributes to the growth and maintenance of muscle mass1, and carbohydrates contribute to recovery of normal muscle function after highly intensive exercise2. Mixing a serving straight after training is one of the most consistent ways to hit your post-session nutrition targets.
Others find mass gainers most useful as a between-meal shake or a calorie-dense breakfast when appetite is low in the morning. There's no single right answer — the best time is whenever your diet has its biggest shortfall. Consistency matters far more than perfect timing, so find a slot that works for your routine and stick to it.
Mass Gainer Benefits
Concentrated Calorie Intake
The most immediate advantage of a mass gainer is calorie density. A single serving can deliver hundreds of calories from a combination of protein and carbohydrates — something that would take a full meal to replicate. For anyone in a calorie surplus phase, that convenience is hard to overstate.
High Protein Per Serving
Weight gainers are built around a strong protein foundation. Protein contributes to the growth and maintenance of muscle mass1, making it a non-negotiable part of any gaining phase. A product like Impact Whey Mass Gainer delivers 30g of protein per serving, giving you a meaningful dose in every shake.
Significant Carbohydrate Content
Carbohydrates are the primary energy substrate for intense training, and mass gainers are loaded with them. Impact Whey Mass Gainer provides 50g of carbohydrates per serving — a substantial contribution to daily intake, particularly after demanding sessions when glycogen replenishment is a priority. Carbohydrates contribute to the recovery of normal muscle function after highly intensive and/or long-lasting physical exercise leading to muscle fatigue and the depletion of glycogen stores in skeletal muscle2.
Convenience When Appetite Is the Barrier
Eating enough to gain weight isn't always enjoyable — appetite fatigue is real, and forcing down a fifth meal of the day gets old fast. A mass gainer removes that friction. Blend it up, drink it down, and you've added a serious chunk of calories to your day without sitting at a table for another hour.
Popular Picks
Impact Whey Mass Gainer — Built for those who struggle to eat enough, Impact Whey Mass Gainer packs 388 calories, 30g of protein, and 50g of carbs into a single serving.
FAQs
What is a mass gainer?
A mass gainer is a high-calorie supplement combining protein and carbohydrates in a single serving, designed to help people increase their daily calorie and macronutrient intake. Unlike standard protein powders, weight gainers prioritise calorie density — making them a practical choice for anyone who struggles to eat enough through food alone. Protein contributes to the growth and maintenance of muscle mass1, while carbohydrates contribute to recovery of normal muscle function after highly intensive exercise2.
What is the difference between a mass gainer and a protein powder?
A mass gainer is formulated to deliver a high volume of both calories and carbohydrates alongside protein, whereas a standard protein powder focuses primarily on protein with minimal carbohydrates and fat. Weight gainers are built for calorie surplus phases, while protein powders tend to suit those who are already meeting their calorie targets and simply need extra protein.
How many calories are in a mass gainer shake?
Calorie content varies between products, but a well-formulated weight gainer supplement typically delivers several hundred calories per serving from a combination of protein and carbohydrates. Impact Whey Mass Gainer, for example, provides 30g of protein and 50g of carbohydrates per serving — making it one of the more substantial options available for those focused on building size.
When should I take a mass gainer?
The best time to take a mass gainer is whenever your daily calorie intake has its biggest shortfall. Post-workout is a popular choice, as the body needs both protein and carbohydrates after intensive training. Others prefer using a weight gainer as a between-meal top-up or a convenient morning shake when appetite is low. Consistency across the day matters more than hitting a precise window.
How much protein is in a mass gainer?
Protein content differs across products, but a quality mass gainer should provide a meaningful dose per serving. Impact Whey Mass Gainer delivers 30g of protein per serving — a solid contribution to daily intake. Protein contributes to the growth and maintenance of muscle mass1, so getting sufficient protein across the day is an important part of any gaining phase.
Can I use a weight gainer as a meal replacement?
Mass gainers are designed as calorie-dense supplements rather than nutritionally complete meal replacements. They work best as an addition to a balanced diet — filling in the gaps where whole food intake falls short — rather than replacing structured meals. Think of them as a top-up tool rather than a substitute for eating well.
Are mass gainers suitable for beginners?
Mass gainers are appropriate for anyone who genuinely struggles to consume enough calories and macronutrients to support their training, regardless of experience level. Beginners who are training consistently and finding it difficult to gain size through food alone can use a weight gainer supplement in the same way as more experienced athletes — as a practical addition to their daily nutrition.
Who developed the mass gainers at Myprotein?
Myprotein's mass gainers are developed by an in-house team of expert nutritionists who specialise in sports and performance nutrition. Every formulation is built around the macronutrient requirements of people in active gaining phases, with protein and carbohydrate ratios chosen to support serious training demands.
What flavours and formats do mass gainers come in?
Mass gainers at Myprotein are available as powders in a range of flavours, designed to mix into a shake with water or milk. Flavour options vary by product, giving you the flexibility to find something that fits your taste preferences and makes hitting your daily calorie target less of a chore.
How do I choose the right mass gainer?
The right weight gainer depends on how many additional calories you need and what your training looks like. If you want a product with a strong protein base alongside substantial carbohydrates, Impact Whey Mass Gainer — with 30g of protein and 50g of carbohydrates per serving — is a straightforward option. Look at the macro breakdown first, then consider flavour and serving size to find a fit for your routine.
1. Protein contributes to the growth and maintenance of muscle mass.
2. Carbohydrates contribute to the recovery of normal muscle function (contraction) after highly intensive and/or long-lasting physical exercise leading to muscle fatigue and the depletion of glycogen stores in skeletal muscle.