DHEA

Is DHEA safe?

For a healthy adult taking a common supplement dose for a few months, DHEA is usually well tolerated. The catch is that it is not a vitamin or a herb. It is a steroid hormone that the body turns into testosterone and oestrogen, and that is why it is prohibited in sport, controlled in Canada and the UK, and a poor choice for anyone with a hormone-sensitive cancer. It scores 57, close to St John's wort and below saw palmetto.

DHEA levels fall with age, which is how it came to be sold as an anti-ageing pill in the US. The best test of that claim was a 2-year randomised trial published in the New England Journal of Medicine in 2006. Older men and women given DHEA had higher hormone levels but no meaningful change in body composition, physical performance, insulin sensitivity or quality of life. It also found no major adverse effects, which is the reassuring half of the result.

What are the side effects of DHEA?

Most side effects come from its conversion into sex hormones:

• Acne and oily skin, the most common complaint in trials.
• Unwanted hair growth on the face and body in women, and sometimes hair loss.
• Menstrual changes and, in men, breast tenderness from conversion to oestrogen.
• Mood effects. Memorial Sloan Kettering lists mania after high doses.

Supplements are commonly sold as 25, 50 or 100 mg capsules, which is far more than the only FDA-approved form. Intrarosa, a prescription treatment for painful sex after menopause, delivers 6.5 mg of prasterone (the drug name for DHEA) as one vaginal insert daily at bedtime. Its label warns that oestrogen is a metabolite of prasterone and that it has not been studied in women with a history of breast cancer.

Does DHEA increase cancer risk?

There is no proof that it causes cancer, but there are good reasons for caution. Health Canada warns that DHEA could increase the risk of prostate, breast, ovarian and other hormone-sensitive cancers. Memorial Sloan Kettering notes that high blood DHEA levels have been associated with breast and ovarian cancer risk, that supplementation has been followed by prostate cancer flare-ups, and that raised DHEA-S levels have been linked to tamoxifen resistance in breast cancer.

That puts several groups firmly in the "talk to your doctor first" category: anyone with current or past breast, ovarian, uterine or prostate cancer, men with a raised PSA, and women taking tamoxifen or other hormone treatment.

Interactions

• Tamoxifen and hormone therapy for cancer. MSK advises against combining DHEA with tamoxifen.
• Oestrogen, testosterone and other hormone treatments, whose effects DHEA adds to.
• Drugs that change DHEA levels. MSK lists alprazolam, amlodipine, diltiazem and metformin as raising them and dexamethasone, insulin and morphine as lowering them, though the clinical relevance is not known.

Tell your doctor you take it before any hormone blood test, since it changes the levels being measured.

Is DHEA legal, and is it banned in sport?

The rules differ more than for almost any other supplement on this site. In the US, DHEA is sold over the counterOver-the-counterA medicine you can buy without a prescription, in a pharmacy or shop, with directions on the pack for safe use without a doctor.More in the glossary as a dietary supplement. Health Canada classes it as a controlled substanceControlled substanceA medicine or drug that the law restricts because it can be misused or cause dependence. Countries group them into schedules or classes.More in the glossary and has seized unauthorised DHEA products from shops. In the UK, prasterone (DHEA) is a Class C drug under the Misuse of Drugs Act 1971, listed with the anabolic steroids. Schedule 4 Part II of the Misuse of Drugs Regulations 2001 means possession and bringing it into the country in person for your own use are not offences, but producing or supplying it without authority is, so it cannot be sold as a food supplement. Australia's Poisons Standard (October 2026) lists it in Schedule 4, prescription only, with the extra possession and supply controls of Appendix D for anabolic and androgenic steroids.

For athletes the answer is simple. USADA says DHEA is prohibited at all times under the anabolic agents section of the WADA list, and a positive test counts even if it came from an over-the-counter supplement.

How reliable are DHEA products?

Not very, as far as anyone has checked. A 1998 analysis in JAMA, summarised later in the Cleveland Clinic Journal of Medicine, found US products ranging from no DHEA to about 150% of the labelled amount. Little independent testing has been published since. Because the dose matters for a hormone, choose a product with a USP VerifiedThird-party testingTesting of a supplement by an independent lab to check that it contains what the label says and is free of set contaminants.More in the glossary or NSF mark if one is available, and expect variation if not.

Who should not take DHEA

• People with hormone-sensitive cancers or a history of them, and men with prostate problems.
• Pregnant or breastfeeding women.
• People with heart rhythm problems, blood clotting disorders or liver disease, whom Health Canada advises to avoid it.
• Anyone subject to anti-doping testing.
• Women trying to conceive, unless a fertility specialist has prescribed it.

How we scored it

Organ toxicity (70) and dose safety (62) are the better factors: trials up to two years show mostly mild androgenic side effects. Regulatory actions (30) is the weakest, because DHEA is prohibited in sport and controlled or prescription-onlyPrescription-only medicineA medicine that can be supplied only with a prescription from a doctor or another authorised prescriber.More in the glossary in Canada, the UK and Australia. Product quality (55) and interactions (60) reflect variable content and the tamoxifen warning. Ashwagandha, also sold for stress and energy, scores in the same range for different reasons.