What Creatine Supplements Can and Can’t Do

SUPPLEMENTS · HEALTHY AGING

Creatine has moved from bodybuilding circles to mainstream supplement shelves, and many people in midlife now wonder whether it belongs in their routine. It is one of the better-studied supplements for adults who lift, but the evidence has clear edges.

This guide explains what creatine supplements are, what the research shows for muscle and strength in middle-aged and older adults, where the evidence on bone and memory stands, how people typically take creatine, and who should talk with a doctor before trying it. It is information to help you decide, not a recommendation to start.

What Creatine Is and Where It Comes From

Mayo Clinic describes creatine as a compound that comes from three amino acids, the building blocks of protein. Your body makes some on its own: according to the NIH Office of Dietary Supplements, the liver and kidneys synthesize about 1 gram a day from the amino acids glycine, arginine and methionine. Cleveland Clinic notes that about half of the body’s supply, 1 to 2 grams a day, comes from food.

Animal foods are the main dietary sources. The Office of Dietary Supplements lists roughly 2 grams per pound of beef, 2.3 grams per pound of pork and 2 grams per pound of salmon. Almost all of the body’s creatine is stored in skeletal and heart muscle, where it raises stores of phosphocreatine, a quick energy reserve used to generate ATP at the start of intense effort. That is why creatine is linked to short, hard work such as lifting, and why the same fact sheet says it seems to be of little value for endurance sports like distance running or swimming.

What Creatine Supplements Do for Muscle and Strength

The best evidence for adults in midlife and beyond comes from trials that pair creatine with resistance training. A 2014 meta-analysis in Medicine & Science in Sports & Exercise, available through McMaster University, combined randomized, placebo-controlled trials in 357 older adults with an average age of about 64. Creatine plus training increased fat-free mass and improved chest press and leg press strength more than training alone, though the authors cautioned that the limited number of studies meant more work was needed.

Later analyses pointed the same way. A 2017 meta-analysis in the Open Access Journal of Sports Medicine included 22 studies and 721 participants with average ages of 57 to 70, and found about 1.37 kilograms more lean tissue with creatine than with placebo, along with small additional gains in chest press and leg press strength. A 2021 meta-analysis in Nutrients of adults with an average age over 50 found a similar lean-mass advantage of 1.32 kilograms. It added an important nuance: when studies that used a high-dose loading phase were set aside, creatine no longer produced a greater strength gain than placebo.

Responses also vary from person to person. The Office of Dietary Supplements notes that individuals respond differently, and that vegetarians, who tend to have lower muscle creatine, might see greater responses.

Training Is the Active Ingredient

Creatine doesn’t build muscle on its own. A 2021 review in the Journal of the International Society of Sports Nutrition reports that most studies failed to show a benefit from creatine alone, taken for 30 days or more, on lean mass, and that creatine without exercise is unlikely to produce substantial gains in strength or physical function. The benefits it describes in older adults come particularly when creatine is combined with exercise.

In other words, the supplement can amplify the response to a good program but can’t replace one. Two or three strength sessions a week with steady progression, along with enough dietary protein, remain the foundation. Our guides to how much protein you need and progressive overload cover both.

Bone and Memory: Interesting but Unproven

Creatine is often promoted for bone health, but the strongest trial so far is sobering. In a two-year randomized controlled trial of 237 postmenopausal women with an average age of 59, published in Medicine & Science in Sports & Exercise in 2023, participants took creatine or a placebo while doing resistance training three days a week and walking six days a week. Creatine had no effect on bone mineral density, although it improved some geometric properties of the upper thigh bone near the hip. Mayo Clinic likewise says research does not show a clear benefit for total bone mineral density. For bone, the training itself does the heavy lifting, as our guide to exercise for bone density explains.

Memory is a newer question. A 2024 meta-analysis of 16 randomized trials with 492 adults aged roughly 21 to 76, published in Frontiers in Nutrition, found a modest benefit for memory, with moderate certainty, but no significant improvement in overall cognitive function or executive function. The authors noted that small sample sizes limit how far the findings can be generalized. Mayo Clinic’s summary is fair: early research is suggestive, and more is needed.

How People Take Creatine

The dosing guidance below describes creatine monohydrate, and it falls into two common approaches. Neither is a prescription; dosing is worth discussing with your doctor or a registered dietitian, especially if you take medications.

Approach	Typical amounts in research	What to know
Loading, then maintenance	20 grams a day in four 5-gram portions for 5 to 7 days, then 3 to 5 grams a day	Fills muscle stores faster; loading often adds 1 to 3 kilograms of body mass, mostly water
Steady daily dose	3 to 5 grams a day	Raises muscle stores more gradually; the 2021 review says loading is not necessary

The loading figures come from the Office of Dietary Supplements, while the 2021 review concludes that lower daily doses of 3 to 5 grams are effective for raising muscle creatine and supporting muscle gains. The International Society of Sports Nutrition’s 2017 position stand adds that people should consume about 3 grams a day of creatine in their diet, particularly as they age. If a dose upsets your stomach, Cleveland Clinic suggests splitting the daily amount into smaller servings. Mayo Clinic notes that taking creatine with caffeine might reduce how well it works, though more research is needed.

Safety, Side Effects and Who Should Ask First

For healthy adults, the safety record is reassuring. The Office of Dietary Supplements says creatine is considered safe for short-term use by healthy adults, that evidence supports safe use for several years, and that studies have found no consistent side effects except weight gain. Mayo Clinic says creatine is likely safe for many people at recommended doses for up to five years. Reported stomach upsets such as nausea and diarrhea are largely anecdotal.

Kidneys are the most common worry. The 2021 review concludes that creatine at recommended doses does not cause kidney damage or dysfunction in healthy people, and Mayo Clinic reports that studies in healthy people haven’t found harm to kidney function. That reassurance does not extend to people with existing kidney problems. Cleveland Clinic says there isn’t enough evidence to know whether creatine is safe if you are pregnant or breastfeeding or have diabetes, kidney disease or liver disease, and it notes that in people with bipolar disorder, creatine may increase the risk of mania. If any of these apply, or you take prescription medications, talk with your doctor first.

Choosing a Creatine Product Wisely

Supplements are not vetted like medicines. The U.S. Food and Drug Administration states that it does not have the authority to approve dietary supplements for safety and effectiveness, and that it is up to manufacturers to make sure their products meet safety standards. Mayo Clinic recommends choosing a product that follows recommended manufacturing practices and uses third-party testing.

The Office of Dietary Supplements’ consumer guide names ConsumerLab.com, NSF International and U.S. Pharmacopeia as organizations whose seals indicate a product does not contain harmful levels of contaminants. It also cautions that these seals do not guarantee a product is safe or effective. A plain creatine monohydrate powder with a third-party seal and no proprietary blend is the simplest choice to evaluate.