7-keto-DHEA is a byproduct of dehydroepiandrosterone (DHEA), a chemical that is formed in the body. DHEA is a "parent hormone" produced by the adrenal glands. But the 7-keto form is not converted in the body to steroid hormones like estrogen and androgen. It is often used to speed up the metabolic rate so people have used it to build muscle and reduce the ratio of fat to lean body mass. It improves thyroid gland activity and is said to slow aging, improve memory, and boost immune response.