Skip to Content

Does Mass Gainer Make You Sleepy? (Why It Makes You Sleepy)

I may receive a commission for purchases made through product links on this page, but I always stand by my opinions and endorsements!

So, you’ve decided it’s time to wave goodbye to your thin frame with the help of mass gainer.

Smart choice – many people out there have seen a dramatic transformation with the help of this supplement.

But one thing you’re worried about is whether mass gainer can make you sleepy.

Well, fear not.

We’ve got you covered.

In this article, we cover why mass gainer makes you sleepy, whether all mass gainers make you sleepy, and so much more!


Let’s get started.

Here’s why mass gainer can make you sleepy:

Mass gainer can make you feel sleepy due to the high amount of carbs and artificial sweeteners. These cause a spike then a fall in your blood sugar levels, which can make you feel low on energy.

Man yawning

3 Reasons Why Mass Gainer Makes You Sleepy

Mass Gainer Can Make Your Workouts More Intense

Mass gainer contains a variety of ingredients that can make your workouts more intense.

For example, creatine boosts ATP levels, which is what your muscle cells use for energy.

So in theory, the more ATP your muscles have, the more reps you can churn out.

By doing more reps, your muscles will be more fatigued which can make you feel tired.

Also, you’ll burn more calories by doing more reps.

And the more calories you burn, the more calories you’ll need to eat to be in a calorie surplus.

So if you’re not eating enough food, you may feel low on energy during the day.

Mass Gainer Is High In Carbs

Most mass gainers are high in carbs, as they’re your muscles preferred energy source and they help replenish your glycogen stores.

When you consume carbs, your blood sugar levels rise sharply as the carbs are broken down to sugar.

But high blood sugar levels are toxic to your body.

So your body responds by releasing insulin which tells your cells to take in the sugar.

As a result, your blood sugar levels sharply drop.

This sudden spike and drop in blood sugar often leads to an energy crash, which can cause tiredness.

Mass Gainer Is High In Artificial Sweeteners

What do the following popular mass gainers have in common?

  • BSN True-Mass
  • MuscleTech Mass Tech
  • Optimum Nutrition Serious Mass

Answer: They’re full of artificial sweeteners.

Now, the thing about artificial sweeteners is that they can spike your insulin levels.

For example, a study compared insulin levels of those who consumed a common artificial sweetener, aspartame, with a meal, with those who consumed a natural sweetener with a meal.

The results showed that those in the aspartame group had a significant increase in insulin levels compared to those in the natural sweetener group.

What’s this got to do with feeling sleepy? I hear you ask.

Well, by spiking your insulin levels, you’ll have an even bigger drop in blood sugar levels.

Which as covered earlier, can make you feel low on energy.

(This also explains why pre workout makes you crash.)

Can Too Much Mass Gainer Make You Feel Sleepy?

Generally speaking, the more mass gainer you take, the more likely you are to feel sleepy.


Well, you’ll be consuming more carbs and more artificial sweeteners.

As a result, you’ll have a bigger blood sugar spike followed by a bigger blood sugar crash.

This big change in blood sugar levels is more likely to leave you feeling drained.

Do All Mass Gainers Make You Feel Sleepy?

It’s very unlikely that all mass gainers will make you sleepy.

One reason is that we’re biologically unique, and so we’ll all react differently to different mass gainers.

For example, Mass Gainer A may make you feel tired, but do nothing to me.

Whereas Mass Gainer B may make me feel tired, but do nothing to you.

Also, there are some great mass gainers out there that are free of artificial sweeteners.

One of my favorites is called Naked Mass, which contains only 3(!) ingredients.

You can see the latest price and read more reviews of Naked Mass on Amazon.

Does Mass Gainer Make You Tired The Next Day?

It’s possible that mass gainer will make you feel tired the next day.

One reason is that if it helps you burn more calories in the gym, thanks to the creatine, then you may wake up in a calorie deficit with low blood sugar levels…

…which can make you feel grouchy.

Also, if you’ve pushed yourself harder in the gym as a result of taking mass gainer, then your muscles may be more tired the next day.

Should You Worry If You Feel Sleepy After Taking Mass Gainer?

Absolutely not!

Worrying is a negative emotion which will make you feel even more tired.

The reason you shouldn’t worry is that you know why you’re feeling tired.

Yes, feeling tired all the time can be a sign of something more serious…

But since you know why you’re feeling tired, there’s nothing to worry about!

Should You Take Mass Gainer At Night?

So, if my mass gainer is making me sleepy, should I take it at night? I hear you ask.

Well, I’d be inclined to say yes.

Taking it at night is sensible as it’ll help replenish your glycogen stores, provide your muscles with a some high-quality protein, and may even help you sleep!