What are the possible side effects of creatine?

If you're looking to improve your physical performance, creatine might be a useful addition to your routine. This naturally occurring compound has been widely studied for its ability to support strength gains, muscle growth, and high-intensity exercise performance.

While it can be effective, it’s also important to understand how it works, what dosage is appropriate, and what potential side effects you might encounter.

What is creatine?

Creatine is produced by the liver, kidneys, and pancreas and plays an essential role in producing energy in your body. It's stored in skeletal muscles, where it helps generate quick bursts of energy—ideal for sprinting or lifting heavy weights.

While your body manufactures creatine naturally, you can also get small amounts through food, particularly red meat, poultry, and seafood. However, creatine supplements can raise muscle creatine levels beyond what dietary sources provide, which is why many athletes and bodybuilders turn to them for performance benefits.

Vegetarians and vegans may have lower creatine levels since they avoid animal products. Supplementing with creatine can help restore these levels to support both energy production and muscle strength—something to consider if you're following a plant-based diet.

Creatine monohydrate is the most thoroughly studied type of creatine. Several small studies suggest it's both effective and generally safe, though larger, long-term studies are still needed.

Is creatine bad for you?

In general, no—particularly when it's taken in the recommended amounts. Research supports the idea that creatine is safe for healthy individuals and may even offer additional benefits for certain medical conditions.

Still, it's best to follow guidance from a healthcare professional to make sure it's right for you.

How much creatine should I take?

To get the most benefit with minimal side effects, finding the right dosage is key. Many people start with a loading phase—around 20 to 25 grams per day, split into four 5-gram doses over five to seven days. This is designed to quickly saturate your muscles with creatine.

After that, you can move into a maintenance phase, typically taking 3 to 5 grams per day. Research suggests this is enough to keep muscle creatine levels topped up. Larger athletes may need slightly more—up to 10 grams per day.

If the loading phase bothers your digestion, you can skip it and go straight to the maintenance dose. It'll just take a little longer to reach peak creatine levels in your muscles.

More creatine doesn’t mean more performance. Once your muscles are full, your body simply excretes the excess—so taking more than necessary is wasteful.

Possible side effects of creatine

Creatine is safe for most people when taken appropriately, but some may experience side effects, especially if they stray from recommended doses.

Common side effects include:

  • Weight gain: Creatine can cause muscles to hold water, which may lead to a slight increase in weight. This isn’t fat, but water retention that often makes muscles look fuller.
  • Stomach upset: High doses may irritate your digestive system, leading to gas or diarrhea. Spreading out your doses across the day might help.

Other reported concerns tend to be linked more to dehydration than to creatine itself:

  • Muscle cramps: Some people experience cramps, though some research suggests creatine might actually reduce cramping in situations like dehydration or heat exposure.
  • Dehydration: It’s a common myth that creatine causes dehydration. There’s no strong evidence for this, but staying hydrated during intense training is still essential.
  • Dry mouth: This can occur during workouts due to sweating—even if not directly caused by creatine. Keep water close and sip regularly.
  • Dizziness: Not directly caused by creatine, but it could signal you're not drinking enough water during tough sessions.
  • Hair loss: While often speculated, there’s currently no solid medical evidence linking creatine and hair loss.
  • Liver and kidney damage: In healthy individuals, normal doses of creatine haven’t been shown to cause harm to the liver or kidneys.

Everyone’s response to creatine can vary. While it's considered safe and well-researched, small side effects may still crop up—and stopping or adjusting your dosage often resolves them.

The final say

Creatine is one of the most studied supplements out there, and a number of small studies support its benefits for exercise performance and muscle growth.

Some users may experience mild side effects like digestive discomfort or water retention, but these are usually manageable with smart dosing.

If you have any existing health issues or questions, it’s a good idea to check in with a healthcare provider before starting creatine or any new supplement.

Disclaimer

The advice in this article is for information only and shouldn’t replace medical care. Please speak to your GP or healthcare professional before trying any supplements, treatments, or remedies. Food supplements should not be used as a substitute for a varied diet and healthy lifestyle.

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