Creatine
Creatine is a compound your liver and kidneys make from three amino acids, and muscles use it to refill their energy during short, hard efforts. Meat and fish add some, and supplements add more.
95 %of the body's creatine sits in muscle
~1 g made by the body each day
From food · about 1 g more a day with meat and fish, none on a vegan diet
- Made from 3 amino acids arginine, glycine, methionine
- Most studied form Monohydrate about 88% creatine
- Amount studied 3 - 5 g a day, after an optional loading week
- Helps most with Short bursts sprints, jumps, lifting
Sources: NIH Office of Dietary Supplements, physiology textbooks. Amounts are those used in studies, not a personal recommendation.
Where Creatine Comes From
Creatine is stored in muscle, so the foods that contain it are the muscle of animals. The Caltide food library does not measure it yet, so there is no ranking here.
- Red meatbeef and pork are the richest everyday sources
- Fishsuch as herring, salmon and tuna
- Poultrychicken and turkey
- Milkonly small amounts
- Plant foodsessentially none, so vegans get creatine only from what the body makes, or from supplements
Cooking at high heat turns part of the creatine in meat into creatinine, so well-done meat carries less than rare.
How Creatine Works in Muscle
Every muscle contraction spends ATP, the cell's energy currency, but a muscle holds only enough ATP for a couple of seconds of all-out work. Creatine is the backup. Stored as phosphocreatine, it hands its phosphate group back to the spent ATP and recharges it almost instantly.
That reserve covers roughly the first 10 seconds of maximal effort, the length of a sprint or a heavy set. After that, muscles switch to slower ways of making energy from carbohydrate and fat. This is why creatine helps a lifter or a sprinter and does little for a marathon runner.
How the Body Makes and Uses Creatine Each Day
The liver and kidneys build creatine from three amino acids: arginine, glycine and methionine. A 70 kg man carries about 120 g in all. Each day about 1 to 2% of it breaks down into creatinine and leaves in urine, and what the body makes plus what food adds replaces it.
What Creatine Supplements Add
Supplements raise the creatine stored in muscle in most people, and that is where the gains in strength and repeated sprint power come from. People who start low, such as vegetarians and vegans, tend to see the largest rise. Some people barely respond, usually those whose stores were already full.
Creatine is often paired with beta-alanine, but the two work differently. Creatine recharges energy in efforts of a few seconds; beta-alanine buffers the acid that builds up in efforts of one to four minutes.
Creatine and Kidney Blood Tests
Doctors estimate kidney function from creatinine in the blood, the same waste product creatine turns into. Someone taking creatine, or eating a lot of meat, can show a higher creatinine and a lower estimated kidney function while their kidneys work normally. Mention the supplement before a blood test so the result is read correctly.
Common Creatine Mistakes
Thinking it is a steroid. Creatine is a compound found in meat and made by the body. It is not a hormone, and sports bodies allow it.
Reading the scale as fat. The early weight gain is water drawn into muscle cells along with the creatine.
Paying more for a newer form. Plain monohydrate is the form behind almost all the research.
Caltide does not total creatine yet, because the food data it uses does not measure it.
Creatine Supplements
Supplements are the second source of creatine, and the only practical way to take in more than food gives: studies use 3 to 5 g a day, while a diet with meat and fish supplies about 1 g.
| Form | Creatine in 100 mg | What the evidence says |
|---|---|---|
| Creatine monohydrate | ~88mg | The form in almost all studies of strength and sprint performance |
| Creatine hydrochloride (HCl) | ~78mg | Dissolves more easily; not shown to work better than monohydrate |
| Buffered creatine | - | Sold as gentler on the stomach; in a head-to-head trial it was no better |
| Creatine ethyl ester | - | Much of it turns into creatinine before muscles can use it; did worse than monohydrate in a trial |
Creatine Doses Used in Studies
Two patterns appear in the research. A loading week of about 20 g a day in four doses for 5 to 7 days, then 3 to 5 g a day; or 3 to 5 g a day from the start, which fills the muscles over about a month. Both end at the same place.
Creatine Safety
- Commonweight gain from water; stomach upset with large single doses
- Ask a doctor firstwith kidney disease, in pregnancy, and under 18
Sources: NIH Office of Dietary Supplements, physiology textbooks. Not medical advice.
Related Nutrients
Creatine Sources and References
The figures and claims on this page are checked against these sources.
Questions About Creatine
It refills the energy that muscles burn in short, hard efforts. Muscles store creatine as phosphocreatine, which hands its phosphate back to ADP to remake ATP within seconds during a sprint or a heavy lift.
Yes, from meat and fish. People who eat them get roughly 1 g a day from food, and the body makes about another 1 g. Plant foods contain essentially none, so vegans rely on what the body makes.
Many studies start with about 20 g a day, split into four doses, for 5 to 7 days, then 3 to 5 g a day. Taking 3 to 5 g a day from the start fills the muscles too, just more slowly, over about a month.
Usually a little, in the first weeks. Creatine pulls water into muscle cells, so the scale goes up before any extra muscle is built. It is water held inside the muscle, not fat.
Studies in healthy adults at the usual amounts have not found kidney harm. People with kidney disease, or who take medicines that affect the kidneys, should ask a doctor before taking it.
There is no good evidence that it is. Creatine monohydrate is the form used in almost all the research, and newer forms such as creatine HCl, buffered creatine and creatine ethyl ester have not been shown to work better.
Yes. Creatine breaks down into creatinine, the marker labs use to estimate kidney function, so a supplement can raise the result without any kidney damage. Tell your doctor you take it before a blood test.
Not much. The benefit shows up in repeated short bursts of high-intensity work, such as sprints, jumps and lifting. Studies of long, steady exercise like distance running show little or no effect.
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