Once touted as a way to maintain perpetual youth, DHEA supplements were ripped from the market in 1985 by the FDA due to multiple false claims about the hormone and the fact that many DHEA supplements didn't contain any DHEA. As health standards increased, DHEA was released back on the market in 1994, and the market has been growing ever since due to the belief that it helps with various conditions, from obesity to type II diabetes.
This hormone is in its best form when made by the body. DHEA is considered a parent hormone, in that it changes form in the body to become androstenedione. From there, androstenedione breaks down into individual male and female hormones. DHEA is made by the adrenal glands, which sit just above the kidneys, in both men and women. Men get an extra boost, as the testicles also make DHEA. The hormone's levels in the body tend to decline during the aging process and drop even lower in certain populations with diseases such as depression. You can maintain healthy levels of DHEA with proper nutrition, stress management and exercise.
Extracts of wild yam, specifically wild Mexican yam, can contain DHEA, but the DHEA only shows up once it is processed in a lab. Eating wild yam will not naturally boost the levels of DHEA in the body. Any supplement that calls their wild yam product "natural" is not being completely honest. The extracts from the yam have to be treated to be converted into DHEA. The best wild yam supplements for DHEA are not ones that merely contain wild yam extracts; they have to have been converted to DHEA.
Soy has a similar story to wild yam in that eating soy alone will not increase levels of DHEA in the hen synthesized in a lab, soy will turn into DHEA 7-keto, which is a form that does not break down into estrogen if unused. This indicates that the soy form of DHEA is better for men to use, as an overabundance of estrogen in the male body can lead to increased fatigue and breast development, according to MayoClinic.com.
Most human studies have people supplementing for three months. A few studies have tested the efficacy of supplementation for up to a year, but MayoClinic.com states that no long-term studies have been done to determine side effects. Since DHEA is a hormone, it is best used for short periods of time, as long-term supplementation may be linked to hormonal-type cancers, from breast to prostate cancer.
The National Institutes of Health reports that currently there is evidence to support supplementation with DHEA for schizophrenia, improving the skin appearance of elderly men and women, helping with erectile dysfunction, improving symptoms of certain autoimmune diseases and increasing bone density. The jury is still out on helping with other diseases and age-related issues.