It is important to note that significant amounts of DHEA are made only by humans and primates. Rodents, such as mice or rats, have little circulating DHEA in their blood so any dose given them would be a pharmacological dose.
Unfortunately, most studies involving DHEA have been con- ducted with rodents and many of the "miracle" claims being touted for DHEA have been based upon rodent studies. Much of the extrapolation from
rodent studies to humans may be contradictory and, in fact, some of it has been proven to be false!
The information and recommendations provided within this article have been based upon the latest studies conducted on human subjects.
DHEA is a steroid hormone
produced by the adrenal glands in both men and women. This hormone is considered a key biomarker in determining biological age as it cycles on a life scale in both sexes. It is the only hormone that peaks early in life and starts to fall significantly thereafter.
DHEA is highest during the years of top physical condition, rising rapidly just before puberty, then spiking between ages twenty and twenty-five. It begins declining progressively from that point
forward, reaching a low by the age of sixty and then slowly descends to less than five percent of peak adult levels after age 70.
The clear drop in men past forty is in sharp contrast to testosterone, which declines noticeably in men only after age sixty.
During the peak years between 25 and 30, men are believed to make 1 to 2 mg of DHEA and 10 to 15 mg of DHEAS per day, with women making somewhat lower amounts.
It is believed that approximately half of the androgen and estrogen precursors in the human body come from the adrenal glands' production of DHEA. As a result, the decline in DHEA production by the body reflects itself in the cells.
Based upon the foregoing, it has been suggested that supplementation with DHEA for those individuals 40 and older, bringing their levels back to those of youth, could extend longevity and improve the
quality of life.
This suggestion gains further support in that DHEA, unlike other steroids, does not appear to be regulated by a "feed- back loop". DHEA supplements -except in very high dosages- are not likely to stop the body's own production.
There are many autoimmune conditions of which
systemic lupus erythematosus (SLE) is four times as common in women as in men. Symptoms include painful swollen joints, skin rash, and mouth ulcers.
SLE is more common than previously thought. A study in England found that 200 women out of 100,000 reported symptoms indicative of the illness.
A team of medical researchers from Japan determined that patients with SLE had low DHEA activity.
Physicians at Stanford University Medical Center conducted a study with ten female patients with mild to moderate SLE. The subjects were given 200 mg of DHEA daily for 6 months.
Following DHEA therapy, most of the symptoms were improved. The researchers concluded: DHEA shows promise as a new therapeutic agent for the treatment of mild to moderate SLE.
It is believed that DHEA therapy could benefit other auto-immunity
diseases such as rheumatoid arthritis and multiple sclerosis. However, the studies on lupus have been the only well-controlled ones thus far. Further studies are clearly warranted.
Researchers from the San Diego Medical School evaluated 13 men and 17 women who ranged in age from 40 to 70 years. In a placebo-controlled, cross-over trail,
they provided 50 mg of DHEA nightly for 3 months.
Within two weeks, the DHEA levels in the bloodstreams of those receiving supplements reached those found in young adults. The researchers concluded:
DHEA supplementation resulted in an increase in perceived physical and psychological well-being for both men and women. The subjects reported increased energy, a better mood, and an improved ability to deal with stressful
DHEA has also been found to have a positive effect on memory. When 50 mg of DHEA was administered to subjects an hour before bed, there was a significant increase in recorded REM (dream) sleep for two hours afterward. Dreams are thought to facilitate memory consolidation.
The majority of the research
evaluating the role of DHEA in cancer has been done on rodents. Very little is known about its role in cancer prevention in humans.
As stated earlier in this report, the results of experiments involving rodents can be very different from results of similar studies with human subjects, especially since very little DHEA is found in the bloodstream of rodents.
DHEA levels can predict which women will get breast cancer up to
nine years in advance, and this steroid actually counteracts a well-known cancer-causing substance known as 12-0- tetradecanoyl-phorbol-13-acetate.
Whether long-term DHEA therapy will help prevent cancer in humans is undetermined at this time
As humans age, the tissues develop a resistance to insulin and the
glucose remains in the blood at a higher level. In a recent study 50 mg of DHEA was given daily for three weeks to 11 postmenopausal women. The levels of triglycerides declined and DHEA enhanced tissue insulin sensitivity.
Another study also confirmed significant improvement in insulin sensitivity. The researchers concluded: DHEA replacement may help attenuate age-related increases in insulin resistance.
It appears probable that DHEA has a positive effect in type II adult onset diabetes.
Heart Disease (CVD)
A study involving 49 males younger than age 56 who were survivors of a heart attack were compared to 49 other males of the same age group who had not experienced heart attacks. Those with prior heart attacks had significantly lower levels of DHEA than the
The researches concluded that serum DHEA levels are inversely related to premature myocardial infarction in males and that this association is independent of the effects of several known risk factors for premature myocardial infarction.
Another study correlating DHEA blood levels with the level of premature atherosclerosis in 206 patients under age 50 found that the levels of DHEAS were lower in the men who
had coronary artery disease than the control group. This data lends further support to clinical studies suggesting that DHEA may play an important role in the pathogenesis of coronary disease.
A current study of 1,700 men aged 40 to 70 who had their DHEA levels tested indicated those with the lowest levels were the most likely to have had heart disease, even after controlling for other risk factors such as smoking and diet.
Clinical studies thus far confirm that high DHEA levels are protective of heart disease in men, but not as influential in women. It is probable; however, that supplementation with DHEA can slow the onset of coronary artery disease.
A study was conducted of nine healthy men with an average age of 64 years. Each was given 50 mg of DHEA for 20
weeks at which time it was found that DHEA therapy had significantly elevated natural killer cells that fight infections.
Another clinical study vaccinated a group of elderly volunteers (over 65 years of age) with the influenza vaccine and compared them to another group similarly vaccinated but who had also received 50 mg of DHEA for two consecutive days beginning on the day of the vaccination. The elderly who got the DHEA had a significant improvement in
their ability to develop anti-bodies to the influenza vaccine.
In short term studies on human subjects, DHEA has been found to be beneficial as a supplement in older individuals by improving the immune system.
DHEA may influence women more strongly than men where sexual desire is concerned. DHEA favorable association
with sex drive in women was demonstrated in a Crenshaw Clinic research protocol. Increased levels of DHEA were associated with increased sexual desire.
Only in women, in marked contrast with other mammals, can the ovaries be removed without a predictable reduction of sexual desire. From this, researchers have concluded that human female sexual desire has shifted somewhat from estrogens to androgens like DHEA, and from the ovaries to the adrenals.
In men, the positive effects of DHEA are most apparent in those who have low androgen levels for men, cardiovascular disease and stress are the greatest causes of sexual dysfunction.
DHEA blood levels drop drastically under stress, which is one of the primary reasons that sex drive may decrease with acute or chronic stress, (and why men may lose erections when they worry about performance).
clear from numerous studies that DHEA does boost sex drive, especially in those who have low DHEAS levels.
Aging is associated with a gradual shift from a young state characterized by anabolism, the building-up of muscles and tissues, to an aged state characterized by catabolism, the loss of muscle mass and strength.
DHEA in appropriate replacement doses appears to have remedial effects with respect to its ability to induce an anabolic growth factor, increase muscle strength and lean body mass in aging men and women, with no significant side effects.
Ninety-six patients with coronary artery disease had their DHEA levels measured prior to starting a controlled exercise program. After 12 weeks, there was no change in the levels of DHEA leading
researchers to conclude that exercise training alone has no significant impact on DHEA.
In an earlier study conducted at the University of Rochester in New York, eight healthy young men were given 1,600 mg of DHEA for 4 weeks. The researchers found that DHEA had little influence on energy or protein metabolism.
DHEA in appropriate doses does appear to increase muscle strength and lean body mass in older men and women.
However, it has little or no anabolic affect on younger men with normal DHEA blood serum levels and high dosage use by bodybuilders should be discouraged.
In surgical menopause with the removal of the uterus and ovaries, osteoporosis can occur within two years. After four years, over 60% of women demonstrate osteoporosis because of estrogen
Research conducted in Japan on 120 postmenopausal women 51 to 99 years old found that women with higher DHEA levels were more likely to have stronger bones.
Results of such studies demonstrate that DHEA is converted to estrone in osteoblasts, and this is important in maintaining bone mineral density after menopause.
DHEA therapy has the potential to influence stronger bone
formation, especially in postmenopausal women.
The reports in the medical literature evaluating the relationship of DHEA to weight loss have not been inconsistent.
Studies conducted in 1988 and 1991 under Dr. Nestler at the Medical College of Virginia in Richmond "suggest that DHEA may possess hypolipidemic
and, possibly, anti-obesity properties"
Similar independent studies conducted by Dr. Usiskin and Dr. Welle in 1990 concluded that short-term administration of DHEA, in high doses, did not have much of an influence on weight.
Recent epidemiological studies conducted this year also do not support the theory, based upon rodent studies that high DHEA levels protect against obesity.
appears unlikely that DHEA, regardless of dosage, will facilitate weight loss, however, DHEA may potentially be combined with other weight loss nutrients and herbs to have a synergistic effect. More research needs to be conducted.