What DHEA Is and How It Works

DHEA (dehydroepiandrosterone) is a hormone your body makes naturally in the adrenal glands, the small organs that sit on top of your kidneys. Your body converts DHEA into testosterone and estrogen, the sex hormones that influence muscle, bone, mood, and sexual function. DHEA levels peak in your 20s and decline steadily after that—by age 70, most people have about 80% less than they did at 30.

DHEA supplements are synthetic versions of this hormone, sold over the counter in the United States as a dietary supplement. The idea behind taking DHEA is that restoring levels to what they were when you were younger might reverse some effects of aging or improve athletic performance. The reality is more complicated: the research shows real effects in some situations, no effect in others, and genuine risks that most people do not know about.

Key Takeaways

  • DHEA appears to improve bone density in older women and may help with sexual function in people with low DHEA levels, but the evidence comes mostly from small studies.
  • In healthy younger people, DHEA does not reliably build muscle or improve athletic performance, even though it converts to testosterone.
  • DHEA can raise testosterone and estrogen levels in your blood, which carries real risks: acne, hair loss, mood changes, and in some cases increased cancer risk.
  • DHEA is not tested or approved by the FDA before sale, so purity and dose vary between brands and even between batches of the same brand.
  • People with hormone-sensitive cancers, heart disease, or liver problems should not take DHEA without medical supervision.

What the Research Shows About Bone and Aging

The strongest evidence for DHEA comes from studies in older women with low bone density. A randomized controlled trial published in the New England Journal of Medicine in 1997 found that women over 60 who took 50 mg of DHEA daily for one year gained bone density in the spine and hip, while the placebo group lost it. A smaller study in older men showed similar results. These are human trials, not animal studies or test-tube work, which makes them more meaningful.

However, the studies are small—the largest involved fewer than 300 people—and they measured bone density on X-rays, not whether people actually broke fewer bones. No long-term trial has shown that DHEA prevents fractures. The effect also appears to depend on having low DHEA levels to begin with; in people with normal levels, adding more does not seem to help bone.

Sexual Function and Mood in People With Low DHEA

Several small human trials found that DHEA improved sexual desire and satisfaction in women and men whose DHEA levels were below normal. One study in women with adrenal insufficiency (a condition where the adrenal glands do not work properly) found that 50 mg daily improved sexual function and mood. Another in older men found similar results. These studies involved 20 to 50 people each and lasted weeks to months, not years.

The effect appears real but modest, and again it seems to matter whether your baseline DHEA is low. In healthy people with normal levels, adding DHEA does not reliably improve mood or sexual function in the research. This is an important distinction: DHEA may restore function if you are deficient, but it does not enhance function beyond normal.

Why DHEA Does Not Build Muscle in Healthy People

Many athletes and gym-goers take DHEA hoping it will build muscle the way testosterone does. The logic seems sound—DHEA converts to testosterone—but human trials do not support it. A meta-analysis of randomized controlled trials found that DHEA supplementation did not increase muscle mass or strength in healthy younger people, even at doses of 100 mg daily for months. Some studies showed small gains in lean mass that disappeared when researchers accounted for water retention.

The reason is not fully clear, but one possibility is that in healthy people, the body tightly regulates how much DHEA converts to active testosterone, and taking a supplement does not change that balance much. In older people or those with low baseline DHEA, the conversion may work differently, but the research in that group is sparse.

Real Risks: Hormonal and Cancer-Related

DHEA raises testosterone and estrogen levels in your blood—that is how it works. For some people, that is a problem. Common side effects include acne, facial hair growth in women, male-pattern baldness, mood swings, and sleep disruption. These effects are dose-dependent and usually reversible if you stop taking it, but they can take weeks to fade.

The bigger concern is cancer risk. Because DHEA converts to estrogen, long-term use in women might increase the risk of breast cancer, and in men, the risk of prostate cancer. The evidence is not conclusive—most of it comes from observational studies and animal research, not randomized trials—but it is serious enough that major medical organizations including the American Academy of Family Physicians recommend against DHEA use in people with a personal or family history of hormone-sensitive cancers. People with liver disease, heart disease, or diabetes should also avoid it without medical supervision.

Quality and Dose Variability in Supplements

DHEA is sold as a dietary supplement in the United States, which means it is not reviewed or approved by the FDA before it reaches store shelves. Independent testing by organizations like ConsumerLab has found that DHEA products vary widely in actual dose—some contain 20% less than the label claims, others 20% more. A few have contained unlisted ingredients or contaminants. This matters because the dose determines both the effect and the risk.

If you decide to take DHEA, buying from a brand that has been tested by a third party (ConsumerLab, NSF, or USP certification) reduces but does not eliminate this risk. Even then, you are taking a hormone supplement with real side effects and unknown long-term safety in most populations.

Who Might Benefit and Who Should Avoid It

The clearest case for DHEA is an older person (usually over 60) with documented low DHEA levels and either low bone density or sexual dysfunction. In that situation, a trial under medical supervision makes sense. A doctor can measure your baseline DHEA level, monitor your testosterone and estrogen while you take it, and watch for side effects.

DHEA is not a good choice for healthy younger people hoping to build muscle or improve athletic performance—the research does not support it. It is also not appropriate for anyone with a history of breast cancer, prostate cancer, or other hormone-sensitive cancers; liver disease; or uncontrolled high blood pressure. Pregnant and nursing women should not take it. If you are on hormone therapy or medications that affect hormone levels, talk to your doctor before starting DHEA.

Frequently Asked Questions

Does DHEA actually increase testosterone?

Yes, DHEA raises testosterone levels in your blood because your body converts it. How much depends on the dose, your age, and your baseline hormone levels. In healthy younger people, the increase is usually modest; in older people, it can be more pronounced. The question is whether that increase translates to the effect you want—and for muscle building in healthy people, the research says it usually does not.

Is DHEA safe to take long-term?

Long-term safety is not well established. Most studies last weeks to months, not years. The main concerns are cancer risk in people with hormone-sensitive conditions and ongoing side effects like acne and mood changes. If you are considering long-term use, medical supervision with regular hormone level checks is important.

Can I take DHEA if I am on other medications?

DHEA can interact with medications that affect hormone levels, including some diabetes drugs, blood thinners, and hormone therapies. It can also affect how your liver processes certain medications. Talk to your doctor or pharmacist before starting DHEA if you take any regular medications.

Why is DHEA sold over the counter if it is a hormone?

In the United States, DHEA is classified as a dietary supplement under the 1994 Dietary Supplement Health and Education Act, not as a drug. That means it does not need FDA approval before sale. Many other countries, including Canada and most of Europe, classify DHEA as a drug and require a prescription. The U.S. classification reflects a regulatory choice, not a safety judgment.

What dose of DHEA is used in research studies?

Most studies use 25 to 100 mg daily, with 50 mg being common. Higher doses increase the risk of side effects without necessarily increasing benefit. If you take DHEA, starting at the lower end of this range and monitoring your response makes sense.