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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. Here we recommend some of the best mass gainers UK in 2023.
But first, what exactly are mass gainers?
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. That’s where the best mass gainers UK come in.
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.
For More Power, Combine your Mass Gainer With the Best Pre Workout UK
OUR RECOMMENDATION: Pre Lab Pro
Mass gainers are usually best taken post-workout as they’re crammed with protein, carbs, and fats that will sit too heavy on your stomach if taken before a workout.
So it makes sense that if you want to make the most of your exercise routine – crucial to help you bulk up – you should opt for a separate pre-workout.
We recommend Pre Lab Pro. It contains all the pre-exercise nutrition you need to crush your workout, including two powerful Nitric Oxide boosters to improve oxygen (and fuel) to the muscles, as well as caffeine for a boost of energy.
Pre Lab Pro is also a strong nootropic pre-workout – meaning that taking it will help you feel enthused and committed to your workout.
READ our Full Review on Pre Lab Pro.
Back to the best mass gainers UK…
Types of Mass Gainers
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.
Mmm, tempting. But can you eat all your extra calories in one go? You might be better with a mass gainer
Important Ingredients in the Best Mass Gainers UK
Protein
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 your 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: Oryzatein is the best form of 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.
» See the Best Pre Workout of 2023 «
Carbohydrates
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.
» See the #1 Nootropic Supplement This Year «
Fat
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.
Creatine
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.
We’ve taken all the above into consideration when it comes to our recommendation for the best mass gainers UK.
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.
Best Mass Gainers UK 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 1,150 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 from being a rock-solid high-calorie mass gainer.
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.
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.
Best Mass Gainers UK Under 1,000 Calories
Bulk Mass Gainer
* Formerly known as Bulk Powders Complete Mass
We love Bulk 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 (5g).
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 to do this, and it elevates Mass Gainer above the competition in the sub-1,000 calorie division (Mass Gainer offers 520 cals with 40g protein and 66g of low GI carbs).
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 offers a stellar micronised creatine monohydrate supplement that you can pair with this.
Optimum Nutrition Gold Standard Gainer
The only company to have products make the top 3 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 770 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 109g of carbs from oat flour, potato starch, pea starch and maltodextrin with just 12g of sugar, and MCTs making up the bulk of the 10g 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 is also made to mix in a shaker cup with no blender needed.
» See the Best Pre Workout of 2023 «
