There are many myths and misconceptions about creatine’s side effects.

Some are serious (“Creatine causes kidney stones”), while others are more innocuous (“Creatine keeps you awake”).

Such misinformation deters many from taking creatine and leveraging its various benefits. 

In this article, you’ll learn science-based answers to the top 10 questions I get about creatine’s side effects.

1. Will Creatine Make You Fat?

No.

As I explain in my fitness books for men and women, Bigger Leaner Stronger or Thinner Leaner Stronger, eating more calories than you burn is the only way to gain fat. 

That said, your weight may increase while supplementing with creatine for two reasons: initially, it can cause you to retain more water, and in the long run, it can promote muscle growth.

2. Will Creatine Make You Bigger?

Yes.

Research shows that creatine increases the amount of water held in muscle cells, making your muscles appear bigger.

It also positively affects nitrogen balance and the expression of certain genes, which helps you gain size by boosting muscle growth

And if you want a supplement that delivers a clinically effective dose of creatine, try Legion’s creatine monohydrate powder and gummies.

(Or if you aren’t sure if our creatine monohydrate powder and gummies are right for you or if another supplement might better fit your budget, circumstances, and goals, then take the Legion Supplement Finder Quiz! In less than a minute, it’ll tell you exactly what supplements are right for you. Click here to check it out.)

3. Can Creatine Cause Acne?

There’s no evidence that creatine causes acne or makes existing acne worse. 

In fact, some research suggests that topical creatine can improve the skin’s appearance by protecting against oxidative and UV damage. It may also stimulate collagen synthesis, tightening saggy skin and reducing wrinkles. 

4. Can Creatine Cause Hair Loss?

One study by scientists at Stellenbosch University found that creatine raised levels of dihydrotestosterone, or DHT, a hormone that hastens hair loss in susceptible men.

Specifically, they found that the standard protocol of taking 20 grams of creatine daily for a week, followed by 5 grams daily for 2 weeks, increased DHT levels in male rugby players by ~40-to-60%.

That said, the study had several limitations (one being they didn’t actually measure hair loss, just a hormone often associated with it), and scientists haven’t replicated the results since. Thus, there’s scant evidence creatine causes hair loss.

5. Can Creatine Cause Kidney Stones?

There’s no evidence creatine causes kidney stones, even in people with a history of kidney stones.

Similarly, research shows that creatine doesn’t put undue stress on the kidneys or raise creatinine (a substance your body creates when metabolizing creatine that can indicate kidneys issues) to harmful levels.

What studies do show, however, is that creatine doesn’t cause kidney damage of any kind, provided you have healthy kidneys to begin with. 

6. Can Creatine Cause Headaches?

There’s no evidence creatine causes headaches. 

A possible reason some people experience headaches when they supplement with creatine is that they train harder and, thus, sweat more, causing them to dehydrate, which can exacerbate headache symptoms. 

To avoid dehydration, drink to thirst before, during, and after your workout. 

7. Can Creatine Cause High Blood Pressure?

There’s no evidence creatine causes high blood pressure.

Creatine causes your muscle cells to hold more water. In theory, increasing “intracellular water” may cause blood volume to rise, elevating blood pressure. 

However, several studies show that creatine has no significant effect on blood pressure. 

8. Will Creatine Make You Bloated?

During the first 5-to-7 days of supplementing with creatine, taking a higher dose of 20 grams per day can speed up creatine accumulation in your muscles (a strategy referred to as “loading”). 

If you load creatine, your body may retain more water than if you took smaller doses, potentially leading to a temporary feeling of bloating. That said, most of this water will be contained in your muscles, which makes them look bigger (not your belly). 

If you’re worried about this potential bloating effect, skip a loading phase and take 3-to-5 grams daily instead. Research shows this will improve your performance by about the same amount as “loading” 20 grams of creatine per day, but has a lower chance of causing bloating or stomach discomfort. 

9. Will Creatine Keep You Awake?

No. 

Creatine isn’t a stimulant, so it won’t keep you awake if you take it before bedtime.

That said, some animal research suggests taking creatine reduces total and deep sleep duration. 

While reducing sleep duration and quality usually harms mental and physical performance, other studies show that taking creatine makes you mentally and physically sharper, even when sleep deprived.

While speculative, this could mean creatine reduces your need for sleep and offsets any negative effects of insufficient sleep quantity and quality. 

10. Are Creatine Supplements Safe?

Absolutely.

Research shows supplementing with creatine is safe, even when taking large daily doses (30 grams per day) for several years.