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Best mass gainer: Bulk up faster with the best protein and carbohydrate supplements

Support your workout regime and get ripped with a supplement to help you pack on muscle mass

It’s vital to back up any training regime with equally well-considered work in the kitchen, but it’s not always easy to get all the nutritional support your body needs from your meals. That’s why many people turn to supplements, and when they really need to pack on muscle quickly, they turn to mass gainers.

Mass gainers are high-calorie supplements that contain a large amount of protein and carbs. They’re designed to help you add weight and, more specifically, muscle mass. They’re useful for skinny types who don’t add muscle easily, along with people of all body types who are training very intensely. They can also help anyone who is underweight and struggling to get the nutrition they need from their regular diet.

Below you’ll find our picks of the best mass gainers available right now, but first, let’s dive into the details you need to help you select the right supplement for you.

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Best mass gainer: At a glance


How to buy the best mass gainer for you

How do mass gainers differ from protein powder supplements?

Mass gainers and protein powders both contain generous portions of protein, but mass gainers are much higher in carbohydrates and some fats than protein powders are. This also means they’re much higher in calories per serving. Protein shakes often boast about how little they contain aside from protein, but mass gainers are proud to pack in the carbs as well as huge amounts of protein.

How many calories are in mass gainer supplements?

Mass gainers usually contain 500 or more calories per serving. Some high-calorie products can have 1,500 cals per serving. This will help if you’re training hard with the aim of bulking up, because you’ll need to consume far more than the recommended 2,500 daily calories for men and 2,000 for women, and that can be hard to achieve through food alone.

What protein, carbohydrate and other contents should I look for?

The ratio of carb to protein in a mass gainer is usually 2:1 or 3:1. Per serving, that means about 70g (rising to as much as 250g) of carb and about 40g of protein.

The type of protein contained in mass gainers tends to be a blend of whey and casein protein. Whey is absorbed much faster than casein, so the blend delivers a hit of protein after your workout and then a steady stream throughout the day. Look for mass gainers that contain “isolate” whey, which is purer and absorbed more rapidly than whey concentrate.

Whey is a by-product of cheese production, so it’s not vegan. However, there are plenty of vegan mass gainer and protein powder options, which use high-quality non-dairy protein sources such as soy and pea.

The best mass gainers contain complex carbohydrates rather than just fast-release sugar. Look for products that use carb sources such as oat powder, which offer extra fibre and sustained energy release.

Most mass gainers include other ingredients designed to give your workout the edge. Creatine, for instance, is a natural substance that helps the muscles convert energy, and is especially helpful in high-intensity workouts. Many supplements will also contain vitamins and minerals.

How much do I need to spend on a mass gainer?

Mass gainers cost around £10-£20 per kilo, and you’ll usually get a better deal if you buy in bulk. A serving size tends to be around 150g-250g, but can be as much as 350g depending on the product and your needs, so take that into account when assessing the price. Even a 3kg tub can be used up in a couple of weeks if you take a sizeable serving every day.

READ NEXT: Make the most of your workouts with the best protein powders

The best mass gainers to buy

1. Optimum Nutrition Serious Mass: The best high-calorie mass gainer

Price: £35 (2.73kg) | Buy now from Holland and Barrett

If you’re in serious need of some extra calories to help you bulk up, Optimum Nutrition’s Serious Mass is a good bet, even if you’ll go through a tub in rapid fashion due to the large serving size. It’s hard to argue with the numbers offered by this mass gainer powder, with a truly monstrous 1,250 calories per serving, including 252g of carbs. There are 25 vitamins and minerals thrown into the mix as well, and Serious Mass comes in a good range of flavours that go beyond the standard chocolate, vanilla and strawberry trio to include slightly more exciting options such as chocolate peanut butter.

Key details – Serving size: 334g; Calories per serving: 1,250; Protein per serving: 50g; Carbs per serving: 252g

Buy now from Holland and Barrett


2. BSN True Mass: The best premium mass gainer

Price: £44 (4.8kg) | Buy now from Discount SupplementsBSN’s high-quality protein blend contains both whey and casein to fuel your muscles throughout the day and provides 10g of naturally occurring BCAAs and 20g of essential amino acids. The carb count in a serving is a little less than other gainers, which will appeal to those aiming to build lean mass, and of the 85g of carbs, only 16g comes from sugars. The flavour range offers all the classics – chocolate, strawberry, vanilla and cookies and cream.

Key details – Serving size: 165g; Calories per serving: 700; Protein per serving: 46g; Carbs per serving: 85g

Buy now from Discount Supplements


3. Bulk Powders Complete Lean Mass: The best lean mass gainer

Price: £40 (2.5kg) | Buy now from Amazon

If you want to bulk up but find the incredibly high carb and calorie counts in the other mass gainers on this list alarming, then you might find that this lean mass gainer powder is more up your street. It contains a 1:1 ratio of protein to carbs at 34g apiece, and 338 calories in an 85g serving, so it’s still providing more than you’d get from a standard protein powder, but in a ratio that’s designed to help build lean muscle, rather than pure bulk.

Key details – Serving size: 85g; Calories per serving: 338; Protein per serving: 34g; Carbs per serving: 34g


4. The Protein Works Total Mass Extreme Matrix: The best-tasting mass gainer

Price: £84 (4.24kg) | Buy now from Amazon

Whether you’re using mass gainer shakes to replace meals or having them as extra meals, it’s definitely worth finding one you enjoy the flavour of, given that they’re going to be providing a fair chunk of your daily nutrition.

The Protein Works Total Mass Extreme Matrix comes in an extensive range of flavours, and some of the more novel ones are sure to add a bit of excitement if you’re tired of the standard protein shake trio of chocolate, strawberry and vanilla. The highlights include Cinnamon Cereal Milk, Tiramisu Italiano and White Choc Peanut Sundae. It’s worth noting that not all of the range is on Amazon, so visiting The Protein Works site directly might reveal the flavour that really tickles your taste buds.

When it comes to the nutrition in the shake, you’re getting 52g of protein from a trio of sources: whey concentrate, micellar casein and soy. There’s a huge 163g of carbs in a serving, too, and once again a combination of sources is used, including maltodextrin and oat flour. To beef up the calorie count to nearly 1,000 per serving, The Protein Works has added medium chain triglycerides fatty acids into the mix, and there’s also creatine monohydrate and a blend of vitamins and minerals in there as well.

Key details – Serving size: 265g; Calories per serving: 974; Protein per serving: 52g; Carbs per serving: 163g


5. MyProtein Oats & Whey Protein Bar: The best mass gainer bar

Price: £48 (18 bars) | Buy now from OnBuy

Bars are an alternative to downing a shake or two every day. It’s not possible to match the vast calorie counts you get in some powders, because the bar would have to be comically large, but you still get a whole load of protein, carbs and calories in a serving, and bars are more convenient to carry around and more of a tasty treat than a thick shake.

The MyProtein Oats & Whey bar comes in four different flavours – chocolate chip, chocolate peanut, real raspberry and salted caramel – and packs an awful lot of nutrients into a pocket-sized package. Each bar contains 324 calories, 22g of protein and 38g of carbs, making it a great option for those looking to build mass, as well as endurance athletes trying to refuel after a long session.

Key details – Serving size: 88g; Calories per serving: 324; Protein per serving: 22g; Carbs per serving: 38g

Buy now from OnBuy


6. The Protein Works Vegan Mass Gainer: The best vegan mass gainer

Price: £36 (2kg) | Buy now from The Protein WorksIf you’re looking to pack on mass while sticking to a plant-based diet, look no further than this excellent supplement. The 30g of protein in a serving of this vegan gainer is a blend of soy, rice and pea protein containing all the amino acids you need to repair and build muscle, while the 72g of carbs come from a mix of fast-acting maltodextrin and slow-release oats. The powder is also high in fibre at 12g a serving, which is always a bonus.

Key details – Serving size: 150g; Calories per serving: 525; Protein per serving: 39g; Carbs per serving: 72g

Buy now from The Protein Works


7. Bulk Powders Mass Gainer: The best-value mass gainer

Price: £49 (5kg) | Buy now from Bulk

If you’re going bargain hunting with your gainer then it’s well worth checking out Bulk Powders’ Complete powder, which comes in at under £10 per kilo when you buy a 5kg bag at full price and is almost always discounted to make its price even more enticing.

The powder delivers the goods nutritionally as well, with 538 calories, 66.4g of carbs and 40.3g of protein in each serving. Those numbers are slightly shy of most of the other options on this list, but that’s mostly a reflection of the smaller 135g serving size of Bulk Powders’ gainer. If you want more calories, you can always increase the amount you use in your post-workout shake.

Oats are the main source of carbohydrates in the powder, while the protein is a mix of fast- and slow-release sources to keep your muscle well fuelled throughout the day. The flavour range is fairly standard, with six different options, and you can also get 1kg or 2.5kg sacks if you want to try it out before going all-in on 5kg. The best value is to be found on the largest size, mind.

Key details – Serving size: 135g; Calories per serving: 538; Protein per serving: 40.3g; Carbs per serving: 66.4g

Buy now from Bulk


8. SCI-MX Nutrition Muscle Meal Lean: The best meal replacement shake for making gains

Price: £90 (5.17kg) | Buy now from Amazon

When you’re looking to add mass, every meal is important. If you’re struggling to plan out your meals to deliver all the nutrients you need, then a meal replacement shake can be a very handy option to use instead.

SCI-MX Nutrition’s Muscle Meal Lean isn’t loaded with as many calories and grams of protein as some of the gainers on this list, but it still provides plenty of both and acts as a more balanced replacement for a meal. Indeed, each shake has a solid 422 calories and contains 48g of protein and 46g of carbohydrates.

The shake also contains a range of vitamins and minerals to provide some of what you’d get from eating a regular meal, but do note that the shake shouldn’t be used to replace all your meals. You’d start to get tired of it anyway, since it only comes in three flavours – the classic trio of chocolate, strawberry and vanilla.

Key details – Serving size: 110g; Calories per serving: 422kcal; Protein per serving: 48g; Carbs per serving: 46g