Like other steroid hormones, testosterone is derived from cholesterol with the largest amounts produced by the testes in men and lesser in the ovaries of females (ratio 10:1). Only small amounts are secreted by the adrenal glands. When testosterone levels are low, a trigger on the pituitary gland to release two hormones stimulate the testis to produce and regulate its levels in the bloodstream.
Testosterone is found in mammals, reptiles, birds and other vertebrates. Being the principal male sex hormone, its androgenic properties are crucial to the development of male reproductive tissues such as the testis and prostate, and promote secondary male sex characteristics (in both men and women) such as voice deepening and hair growth patterns. As an anabolic steroid, it promotes secondary sexual characteristics such as increased muscle and bone density, thus for prevention of osteoporosis.
Main causes of low testosterone -
Early infancy androgen effects commence in the first weeks of life for male infants, with testosterone levels rising with a decline seen in both sexes in the later decades of adult life. The normal value for total testosterone in males is 270-1000 ng/dl. As men get older, the testosterone-producing Lyedig cells of the testicles decline in function and size, resulting in decreased production, termed "hypogonadism". As much as women hit 'menopause', men reach "andropause" with much decline in this hormone.
+ When the problem is in the organs that produce testosterone (the ovaries or testes, for the most part), it is called a "primary" problem. This failure of the gonads can be due to:
++ Undescended testicles at birth
++ Injury to the scrotum
++ Cancer therapy
++ Genetic birth defect
+ When the problem is related to the pituitary and its ability to regulate testosterone, it is called "secondary hypogonadism." It can be due to:
++ Tumors of the gland itself or because of damage caused by the side effects of treatment of nearby brain tumors
++ Excessive blood loss in the brain
++ Inflammation caused by AIDS, HIV and tuberculosis
++ Illegal use of anabolic steroids as in body building
++ Obesity specifically enhances the conversion of testosterone to estrogen
Other factors affecting testosterone levels -
- Weight loss makes fat men more masculine. Fat cells synthesise the enzyme aromatase which converts testosterone into estradiol, the female sex hormone. A four point increase in body mass index accelerates natural decline in testosterone by 10 years.
- The hormone vitamin D in levels of 400-1000 IU (10-25 mcg) raises testosterone level.
- Magnesium and zinc raise free testosterone according to studies.
- Strong motivation drives the testosterone up.
- Lack of sleep can lower testosterone levels.
- Diets with limiting fat to less than 10% of the total calories can significantly reduce testosterone levels.
- Alcohol drinking can result in lower testosterone secreted from the testicles and thus its circulation in the blood.
- Constant exposure to endocrine disruptors such as environmental contaminants.
Some research found that intense aerobic exercises can lead to lower than average testosterone levels because of a decrease in the pituitary gland's ability to signal the testicles to produce more testosterone. On the other hand, resistance training increases testosterone levels because testosterone has to be released for muscle-building purpose. Thus, combining both help to reverse the decline. Adequate rest is important as over-training can cause the body to reduce testosterone output too.
Time matters...
+ In males, symptoms of decreased testosterone depend upon when the low levels occur.
- If there is inadequate testosterone in the foetus, genital formation may be affected. In extreme cases, the penis and scrotum can be so badly developed that female or ambiguous genitalia appear. Hence, it is the chromosomal composition and not the outward appearance that matters.
- If low testosterone occurs before or during puberty, there may be a lack of sexual maturation. Signs may include failure to develop muscle mass, failure of the voice to deepen, poor hair growth, enlarged breasts and failure of the penis and testes to enlarge.
- In adulthood, low testosterone may lead to decreased intellectual ability and spatial orientation, depression, lethargy, decreased sexual function and desire, infertility, erectile dysfunction and absence of morning erections, hot flushes, hair loss on upper body and osteoporosis.
+ Whilst low testosterone is usually associated with males, low levels may occur in women and cause significant issues. Symptoms may include hot flashes, irritability, loss of sexual desire, sleep disturbances, loss of hairs, reduced muscle mass and bone density.
High testosterone?
Much less likely is the opposite scenario: A T score that tops 1000 ng/dl. Other than steroid abusers, this condition is extremely rare other than caused by glandular cancer.
Detection
A medical test can be conducted to check on the testosterone, albumin and sex hormone binding globulin levels in your blood. As testosterone levels fluctuate significantly in the bloodstream, being highest in the morning, it is advisable to take the test between 7-11 am for best accuracy.
How about estrogen?
Just the reverse - the hormone estrogen is produced in greater amounts by females and less by males. An appropriate amount of estrogen is required in the male in order to ensure well-being, bone density, libido, erectile function, etc.
Exceptionally high levels of estrogens in men lower testosterone, decrease muscle mass, stunt growth in teenagers, enhance feminine characteristics and increase risk to prostate cancer, reduce libido and cause erectile dysfunction.
What foods can boost testosterone levels?
Incorporating more fat in the form of monunsaturates (eg. walnuts, peanuts, almonds), animal meat protein and Omega 3 to reach 35-40% of total calories can be optimal for robust testosterone levels. A diet high in sugar can temporarily lower the testosterone levels too. Other foods to watch -
1. Grapes for more active sperm - resveratrol found on grape skins can raise T levels, improve motility rate and hardier sperms
2. Cabbage to flush out female hormone, oestrogen - for more effective testosterone
3. Honey for better blood circulation - a mineral found in it, boron is linked to high testosterone
4. Venison for muscle growth - lack of protein boosts testosterone-deactivating hormones. This meat is not too rich to cause blood-clogging
5. Egg to boost hormone - its yolk is the precursor for testosterone
Testosterone replacement?
Most urologists accept that a total testosterone level above 12nmol/l does not require testosterone replacement.
1. Amongst the many modes of administering testosterone replacement, the most popular being intramuscular injection such as testosterone undecanoate, as the slow release method into the bloodstream over a 10-12 week period results in more stable levels.
2. Transdermal gel application is recommended for short-acting and bypassing liver metabolism for medical reasons. It is applied daily by men rubbing testosterone gel over their upper arms and abdomen till dry.
Source: Men's Health, Mar 2012 edition
No comments:
Post a Comment
This is a blog created to provide and share information for the benefits of everyone into physical and spiritual health. Some information are extracted from unknown sources or the internet superhighways and edited for public viewing. If you happened to be the source provider and do not like such display, please write in and I will remove the materials as soon as possible. As I reiterate this is a free sharing blog, it is only meaningful if all engaging parties have access to the information presented in the most unbiased manner. Thus, please be more accomodating and participative if you wish. Sure you have more to gain than lose. Happy reading!
Administrator
Leonard