Mass Gainers: Who Needs
Them & How to Use Them
A mass gainer can be a legitimate tool — or an overpriced bag of sugar. Here's how to tell the difference and whether you actually need one.
A mass gainer is a high-calorie protein supplement — typically 600–1,200 kcal per serving — designed to help people struggling to eat enough calories gain weight faster. They're not magic. They're not for most people. And many popular ones are mostly cheap carbohydrates with mediocre protein. Here's how to use them correctly if you genuinely need one.
What is a mass gainer?
Mass gainers are simply a blend of protein (usually whey), carbohydrates (maltodextrin, oats, or sugar), and sometimes fats. The goal: deliver a large caloric dose in a single shake, making it easier to hit a calorie surplus for people with small appetites or high metabolisms.
Typical calories
700–1,200
Per serving (2–4 scoops)
Typical protein
40–60g
Per serving
Carb ratio
2:1 to 5:1
Carbs to protein ratio
Who actually needs a mass gainer?
check_circleHardgainers (ectomorphs)
If you have a naturally fast metabolism and genuinely struggle to eat enough whole food to hit your calorie surplus, a gainer shakes things up without forcing 6 large meals a day.
check_circleVery high TDEE athletes
Endurance athletes, CrossFit competitors, and athletes with >4,000 kcal/day needs often can't eat enough whole food around training schedules.
check_circlePost-illness or injury recovery
During medical recovery where muscle atrophy has occurred and appetite is suppressed, high-calorie shakes fill a genuine gap.
Who does NOT need a mass gainer
closeAverage gym-goers looking to "bulk"
If you can hit a 300–500 kcal surplus with real food, a gainer is just expensive maltodextrin. A banana + oats + whey achieves the same thing at a fraction of the cost.
closePeople already eating 3,000+ kcal/day
Adding a 1,000 kcal gainer on top creates an excessive surplus — most of the extra calories store as fat, not muscle.
closeAnyone who hates counting
A single mass gainer serving can wipe out most of your calorie budget. Without tracking, it's easy to accidentally under-eat whole food and miss micronutrients.
What to look for when buying a gainer
Protein source
Whey, casein, or egg as the primary protein — not amino spiked blends
Carb source
Oats, sweet potato starch, or complex carbs over pure maltodextrin/sugar
Protein per 100g
At least 20g protein per 100g dry weight — many gainers are only 10–15g
Sugar content
Under 20g per serving — some gainers exceed 80g sugar per shake
Fats
Some fat is fine (MCTs are ideal); avoid trans fats
The DIY mass gainer (better & cheaper)
Most commercial gainers charge premium prices for cheap carbohydrates. You can build a better shake for less money:
DIY 1,000 kcal Gainer Shake
How to use a mass gainer correctly
- check_circleTrack it in a calorie app — a 1,000 kcal shake is invisible unless you log it.
- check_circleUse it to supplement food, not replace meals. Micronutrients don't come from carb powder.
- check_circleStart with half a serving if you're new to high-calorie shakes to avoid GI distress.
- check_circlePost-workout or between meals is ideal — not first thing in the morning when food is a better option.
- check_circleIf you're gaining more than 0.5–1kg per week, the surplus is too large — reduce the dose.
The bottom line
Mass gainers are a legitimate tool for genuine hardgainers who can't hit their calorie targets through whole food. For everyone else, they're expensive calories. Build your DIY shake, track your intake, and keep the surplus in the 300–500 kcal range. That's where real muscle — not just weight — gets built.
Find your bulking calorie target
Before buying any gainer, calculate your TDEE and surplus so you know exactly how many extra calories you need.
Open Calorie Calculator arrow_forwardKnow your calories. Build your body.
SlayCal makes hitting your bulking target easy — scan your shakes, log your meals, see your progress daily.