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If you’re keen to hit your muscle building goals this year, or have taken whey or other muscle-building supplements in the past, then chances are you’ve also considered taking a mass gainer… but what exactly are they?
Mass gainers are supplements designed to increase your daily calorie intake. They provide a source of lean protein, most commonly whey, as well as carbs and fats, with the aim of building muscle mass.
Most whey protein (concentrate and isolate) contains between 80-90% protein by weight, and with mass gainers this is much less, usually hitting a ratio of 2:1 carbs to protein. This makes them pretty cheap to make and appealing for large supplement manufacturers who already sell whey protein.
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How do Mass Gainers Work?
If you’re a beginner, you need to consume the pretty widely accepted 300-500 extra calories a day in order to build muscle mass, or 20% more than what your body requires to maintain your current weight while undertaking your usual level of activity. Consuming more than your ‘maintenance’ calories is known as a being in a calorific surplus.
Consume less calories than your body needs and you’ll lose weight. Consume more than your body needs and you’ll gain weight. This simple maths will dominate your weight-loss or weight gain success or failure… more or less anyway.
When it comes to gaining muscle, beginners generally require more of a surplus than those who’ve put on 10-15 lbs of muscle already. This kind of high-volume diet can be a real challenge for anyone new to building mass, even if they’ve been lifting and dieting for years without seeing huge gains.
Mass gainers provide a solution to this struggle. Whether it’s a shake post workout or a meal replacement throughout the day, they can be a key to hitting your macro goals.
There are two types of mass gainers. The most common are those designed for post-workout consumption. They usually contain high amounts of quick absorbing carbs to protein and minimal fat. This is ideal, as your body prioritises carbs consumed directly after a workout into repairing muscle, with the emphasis on muscle building and less storing those carbs as fat.
The other kind of mass gainer is more of a meal replacement. Still high in protein and carbs, they will also add more fats to the mix that are vital for processes involved in muscle building like anabolic hormone production. Consuming these at other points in the day, usually in conjunction with that all important post-workout shake, ensures the fats and carbs are timed to optimise muscle building and minimise fat.
Important Ingredients in a Mass Gainer
Whey: This one’s a no brainer, and if you know what you’re looking for when it comes to your ‘normal’ protein shakes then you’ll know what to look for in a mass gainer too. An 80% protein content for a whey concentrate, and 90+% for isolate. This is your quick absorbing, water soluble form of protein that’s shuttled to you muscles and promotes lean mass.
Casein: Casein, or milk protein, is a common ingredient in mass gainers. It’s a longer chained molecule compared to whey and it’s much slower absorbing. You’ll often see both whey and casein used together as this provides a quick rush of protein post-workout followed by the sustained casein release throughout the day (or night).
Egg protein: Eggs never let you down when it comes to protein. Often, whole egg powder or egg albumen (egg white) is included in mass gainers, and while the egg albumen is lean (around 95% protein), whole egg powder — fats included — has been linked with stimulated muscle protein synthesis.
Rice Protein: With an absorption rate comparable with whey protein, rice protein is also a complete protein — meaning it contains all nine essential amino acids. It’s a strong vegan alternative to whey and other milk/ dairy derived proteins.
Pea Protein: The other big player in the plant-based protein market, and often used together with rice protein, pea protein absorbs slower than whey or rice protein, making it a great casein alternative.
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The reason we’re all here, right?
The carbs, often provided as a blend or a matrix, are what makes the mass gainers different to your run-of-the-mill protein shakes. The carbs provide the fuel your body needs in excess to build significant muscle. However, something you’ll want to look out for in mass gainer is their sugar content. Minimal refined sugar in your diet is fine, but in cheaper mass gainers, manufacturers will often add refined sugars to elevate the calorie count and avoid spending on high quality carbs or bulking out the serving sizes.
Maltodextrin: A complex carb that’s soluble in water and very fast absorbing. Coming in at over 100 on the Glycaemic Index, this will give you a spike and crash in blood sugar if you consume more than a tiny amount. So be on the lookout for over-sweet, over-maltodextrined mass gainers.
Dextrose: A common ingredient with a more recognisable name… glucose. It goes without saying that this is high GI and it will spike blood sugar and insulin. The list of long-term health risks of regular high glucose consumption would be too long to include here.
Check your sugars on the nutritional information table and opt for as low as possible.
Oat flour: A solid, healthy choice for carbs in any mass gainer. Even processed into powder, oats aren’t high GI and also contain beta-glucans that are linked with lowered risk of heart disease and diabetes, among a host of other benefits.
Quinoa flour: One of the oldest grains in the world but relatively new to emerge on the mass gainer scene, quinoa flour has a GI of 53, meaning it won’t cause a big spike in blood sugar. With a high fibre content, a spread of vitamins and minerals, as well as being a complete source of protein, it’s a high-quality choice for sure.
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When it comes to fat, most mass gainers tailored for post-workout will be pretty lean, maybe 3-7 grams of fat per serving, and that usually comes from the extraneous ingredients from milk protein, whey or egg.
Medium-chain Triglycerides: When fat is added, this is the most common one you’ll see and it’s also a frequent supplement for athletes. MCTs are man-made saturated fats produced from coconut and palm kern oil, and dairy fat. They’ve been linked to reduced fat and total cholesterol (good and bad) and may improve athletic performance.
It’s not unusual for mass gainers to include up to 5g of creatine in each serving, which is the recommended amount per day and a useful addition. Not only does this mean you won’t have to supplement with additional creatine, consuming it with carbs boosts its absorption and helps shuttle the creatine around your fatigued muscles.
Who Are Mass Gainers For?
If you’re looking to put on size in the gym, maybe for your first time, mass gainers can help you hit those big calorie goals. Because when it comes to mass, the calorie surplus is the route to success, and eating that much healthy food can be difficult. If this sounds familiar, then mass gainers are worth having a look at.
Along with a healthy diet of whole foods, a mass gainer can help push you over into that 20% calorie surplus and take the pressure off getting another meal down.
If you’re an ectomorph body type, or someone who’s really found it difficult to build muscle mass, then exploring mass gainers is definitely worth a shot.
Top 5 Mass Gainers Over 1,000 Calories
Ranking written by Ben Burrell-Squires
PhD Advanced Mass
Kicking off our round up of the best mass gainers over 1,000 calories is PhD Advanced Mass. It tips the scales at just over 1,140 calories and every single one of them has been carefully considered.
There are 3 carbohydrate sources here, from the high-GI, fast acting maltodextrin, to the middling waxy maize starch and finally slow-releasing oat flour. The result is consistent energy delivery for hours after consumption.
The mix of protein sources offers the same consistent release over many hours post workout. We have whey concentrate, whey isolate, micellar casein and whole egg powder.
Completing the formula is a healthy dose of medium chain triglycerides, 5g of creatine monohydrate, a raft of amino acids and BCAAs and flaxseed for alpha-linolenic acid, an essential fatty acid. Oh, and there’s zinc and magnesium too, for good measure.
The result is an almost flawless concoction with only minor flaws and questionable mixability. But that doesn’t stop it being a rock solid high calorie mass gainer.
BUY: Pick it up yourself from the official PhD website.
Optimum Nutrition Serious Mass
If you want to gain serious mass, then you need to take Optimum Nutrition Serious Mass. At 1,250 calories per serving, it’s one of the heaviest hitters we have ever reviewed.
Common problems with high-calorie mass gainers include their high sugar content, poor mixability and the fact that they can leave you bloated and, in extreme cases, nauseous.
Optimum Nutrition half avoid all of these problems. Around 20% of the carbs are sugar, but all the rest come from maltodextrin which is cheap and high-GI. It’s hard to mix but you get there eventually. And it’s not too hard to digest, in fact many users report it’s quite pleasant.
You get 50g of protein from whey concentrate, calcium caseinate, egg whites and sweet dairy whey. It contains creatine and glutamine, but in low doses, plus a stack of BCAAs and other vitamins and minerals. It’s not perfect, but it does the job well.
BUY: Pick it up from the Optimum Nutrition website.
MusclePharm Combat XL Mass Gainer
If you thought we were peaking at 1,250 calories with the last entry then think again, we’ve barely started yet! How about 1,270 calories? That’s what you get from MusclePharm Combat XL Mass Gainer. This includes 50g of protein and over 250g of carbs.
The combination of proteins is great here. We have whey concentrate, hydrolyzed whey, milk protein concentrate and micellar casein providing both fast and slow absorbing protein. The carb weight is mostly made up of maltodextrin, which is not ideal, but MusclePharm do include other powdered carbs including chia, flaxseed, quinoa and brown rice.
MCTs are all present and correct and there is a couple of vitamins and minerals thrown in too. The main draw here though is the sheer number of calories per serving, and one of the best protein blends we have come across in a high-calorie mass gainer.
BSN True Mass 1200
A truly epic mass gainer from a UK company, True Mass 1,200 over delivers slightly on its promise by offering 1,248 calories per serving. This is made up of 54g of protein, 18g of fat (of which 4.9g saturates) and 220g of carbs (of which just 19g is sugars and 15g is dietary fibre).
The engineering that has gone into this formula is pretty impressive. Let’s start with the protein stack. There are 7 different sources of protein in here, including whey concentrate and isolate, calcium caseinate and egg whites. This means you get a full range of quick and slow absorbing proteins to keep your muscles ticking over all day.
Next, the carbs. We have maltodextrin, oat flour and polydextrose in the mix. Like the protein combo, this mix has been designed to give you a rapid energy and metabolic boost and provide plenty of fuel for hours ahead. MCTs are here, but no creatine, which would have been a nice addition. Otherwise it’s damn near perfect.
BUY: Try it yourself from Amazon.
MuscleTech Mass Tech Extreme 2000
Rounding out the top 5 mass gainers over 1,000 calories is this absolute monster from MuscleTech. Mixing the insane serving size of 6 heaped scoops with water will provide 2,060 calories! You could do half portions and still be above the 1,000-calorie mark!
In fact, you might want to consider doing this because trying to get an entire serving down is something only the most extreme gainers will be able to handle. We just love how insane this product is though. The formula is solid – there’s 4 different whey protein sources here and a full serving mixed with water provides 60g of them combined.
Elsewhere we have a mind-boggling 450g of carbs with just 20g of sugar (though it does contain glucose polymers) and a good deal of the carbs are from oat bran. There’s just 5g of fat per serving and some of this is in the form of MCTs.
10g of creatine, 6g of l-leucine, 10g of l-glutamine and a raft of vitamins and minerals complete the formula.
BUY: We dare you to grab some from Amazon.
Top 5 Mass Gainers Under 1,000 Calories
Myprotein Extreme Gainer Blend
We reviewed this product back in February, and you can read the full review here if you like. What we found was that Myprotein Extreme Gainer Blend is an excellent all-round gainer.
It contains multiple protein sources for a total of 35g per dose, plus low-GI carbohydrate sources and medium chain triglycerides to boost the calorie count from fats. As an added bonus, there’s 5g of high-quality creatine monohydrate in there too.
It’s really hard to fault Myprotein because they offer straight down the line quality that’s really affordable. Extreme Gainer Blend hits the spot for taste and mixability as well.
It clocks in at just over 500 calories per serving, so it’s one of the leanest formulas out there. This, plus the price and accessibility of it, make it an ideal choice for anyone from beginner to pro who is looking to boost their calorie intake and pack on mass.
BUY: Grab your bag from the Myprotein website.
Bulk Powders Complete Mass
We love Bulk Powders here at Supplement Reviews UK. They are one of the dominant forces in the UK market, for good reason. This formula contains quick and slow release proteins, low-GI carbs like oats and a fantastic addition in the form of leucine.
Leucine is a BCAA that supports protein synthesis, so when you combine this with enough carbs to raise your insulin level you get the maximum benefit of every protein source in the formula. It’s a smart decision from Bulk Powders to do this, and it elevates Complete Mass above the competition in the sub-1,000 calorie division.
Elsewhere you’ve got an incredibly low sugar content, very little fat, and a price tag that you simply cannot argue with. On the downside, the taste isn’t as good as other products and it can be hard to mix too. It also doesn’t contain any creatine, but Bulk Powders offer a stellar micronised creatine monohydrate supplement that you can pair with this.
BUY: You can buy Complete Mass from Bulk Powders.
Hench Nutrition Hi-Calorie Mass Gainer
With a name like this, how is this one ever NOT going to make our list?! Although the label on the tub says this provides 1,000 calories, that’s only when mixed with milk. Mixing one serving with water will give you 630 calories, which is still far from being the leanest product on our list.
There is just 35g of protein to be had from one serving, which may not be enough for some, but it’s from high quality sources like whey concentrate, milk concentrate and micellar casein. Also, soy isolate features, presumably to beef up the protein total.
The carb total is 102g per serving and this comes from maltodextrin, oats and waxy maize starch – a superior carb form that is becoming popular among carb-loading supplements for its slow-release, low-GI profile.
We have around 7.5g of fat per serving, so it’s nice and lean, and Hench specify that 4g of this comes from MCTs. The big selling point here is the price – at the time of writing you can pick up 4kg of this stuff for around £36. Given the quality of the formula, that’s insane value.
Optimum Nutrition Gold Standard Gainer
The only company to have products make the top 5 in both over and under-1,000 calorie divisions, Optimum Nutrition clearly know what they’re doing when it comes to fueling massive gains. This product replaces their popular Pro Gainer formula and offers a very respectable 763 calories per serving.
This is made up of a stonking 55g of protein from whey isolate, whey concentrate, milk concentrate and hydrolyzed whey isolate, all good quality sources. We have 105g of carbs from oat flour, potato starch, pea starch and maltodextrin with just 10g of sugar, and MCTs making up the bulk of the 12g of fat per serving.
The quality of the carbs is what sets this apart. Starchy carbohydrates are a great source of slow-releasing energy and extremely nutritious – containing a lot of vitamins and minerals. It falls down slightly on taste and mixability, but the nutrient profile is the star of the show here.
The Protein Works Vegan Mass Gainer
Back when we reviewed the best protein products to buy in 2019, we gave The Protein Works top marks for their Vegan Protein blend, and they have smashed it out of the park again with Vegan Mass Gainer, weighing in at a healthy 540 calories per serving.
The Protein Works have taken elements of what made Vegan Protein so successful by incorporating 3 out of the 5 sources into Vegan Mass Gainer. The 39g of protein comes from soy, brown rice and pea which gives a full amino acid profile.
There is almost a 2:1 carb-to-protein ratio here as the carbs weigh in at 90g (12g sugar, 7g dietary fibre) consisting of maltodextrin and oats for a nice sustained release profile. To be expected, there’s barely any fat at all and no mention of MCTs, but TPW have included flaxseed powder for the beneficial alpha-linolenic acid it contains.
BUY: Give it a go from The Protein Works website.