Creatine myths: hair loss, kidneys, and water weight

Where the worries come from

Creatine monohydrate is one of the most studied supplements, yet a few concerns keep circulating. In 2021, eleven researchers published a review that took on twelve of the most common questions, from hair loss to kidney safety. This article draws heavily on that review and on a 2025 trial that looked at hair directly.

One caution up front: the review's authors disclose that the society that published it receives support from companies that make or sell creatine, and two of them serve on the scientific advisory board of a creatine manufacturer. The 2025 hair trial also lists that society's chief executive as a coauthor. That does not make the findings wrong, but it is worth knowing who produced the evidence.

Hair loss: one study, never repeated

The hair-loss idea traces to one 2009 study. Researchers found that dihydrotestosterone (DHT), a hormone linked to male-pattern hair loss, rose in rugby players taking creatine. They did not measure hair, and the result has not been repeated. The 2021 review notes that the creatine group started with lower DHT than the placebo group and that the ratio of DHT to testosterone stayed within normal clinical limits.

The 2025 trial was the first to measure hair directly. After 12 weeks at 5 g a day, men taking creatine showed no change in DHT or in hair density, follicle count or thickness compared with placebo. It was short, small and limited to men, so it does not settle every case, but it is the most direct evidence available.

Kidneys, and the blood test that can mislead

The kidney concern began with a 1998 case report about a person who already had kidney disease and was taking cyclosporine, a drug that affects the kidneys. According to the 2021 review, more than 20 years of research since then has found no harm to kidney function in healthy people at recommended doses.

There is a real lab-test wrinkle. Creatine, like a high-meat diet, can raise creatinine in the blood. Doctors use creatinine to estimate kidney function, so a higher number can make kidneys look worse on paper when they are not. If you take creatine, mention it before routine bloodwork.

The safety research is in healthy people. If you have kidney disease or reduced kidney function, talk with your clinician before using creatine.

Water weight

Early short-term studies found that people gained some weight when they started creatine, mostly water held inside muscle cells rather than bloating under the skin. Longer training studies did not find an increase in total body water relative to muscle.

Loading, about 20–25 g a day for five to seven days, raises muscle stores fastest and is when a quick gain on the scale is most likely. The review notes that 3–5 g a day reaches similar levels over about four weeks and is a better fit for anyone who wants to avoid a sudden jump.

Steroid, dehydration, cramps

Creatine is not an anabolic steroid. It has a different chemical structure and is regulated as a dietary supplement, not a controlled substance.

Reports that creatine causes dehydration or cramps come mainly from surveys. The 2021 review points to controlled data that do not support them, including a study of 72 college football players in which creatine users had fewer cramps and heat-related illnesses than non-users.

Who should check first

Most of this research involves healthy adults. If you have kidney disease, are pregnant or breastfeeding, are under 18, or take prescription medicines, ask a qualified clinician before starting creatine.

This article explains research findings; it does not diagnose, treat, or prescribe.

How we describe our own product

DECLARED Creatine Monohydrate provides 5 g of creatine monohydrate per serving, with no other ingredients. It is unflavored.

We do not describe it as Creapure or any other branded raw material, because we do not have documentation for that claim.