Why Low Testosterone Levels May Be More Common
The following features of modern life may be contributing to declining testosterone levels in men:
- an increase in sedentary lifestyles
- an increase in obesity rates
- an increase in prevalence of impaired sleep
- increased exposure to hormone disrupting chemicals
On Estrogen Levels in Men
Men need to have estrogen in order to be healthy. It’s produced in small amounts by the adrenal glands and the testes. If more is needed to maintain the correct level, testosterone can be converted to estrogen by the enzyme aromatase. This gives your body the best ability to maintain strict control over sex hormone levels.
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On Age-Related Changes
Production of testosterone and sensitivity to it increase during puberty. Men remain sensitive to testosterone throughout their lives, although the amount produced can vary. For example, testosterone levels in adolescent males can fluctuate significantly and should not automatically be a cause for concern.
Your body keeps your testosterone level within a certain range. The amount of your level can fluctuate over time, and the levels for individual men can be different (but still fall within the “normal range”).
When your total testosterone level is tested, the lab report will indicate the normal range they use for reference, which could look like the one below [*]:
| Males, 0-5 months: | 75-400 ng/dL |
| 6 months-9 years: | <7-20 ng/dL |
| 10-11 years: | <7-130 ng/dL |
| 12-13 years: | <7-800 ng/dL |
| 14 years: | <7-1,200 ng/dL |
| 15-16 years: | 100-1,200 ng/dL |
| 17-18 years: | 300-1,200 ng/dL |
| > or =19 years: | 240-950 ng/dL |
Two 25 year old men could have different results; Man A could have a level of 256 and Man B could have a level of 895 but they would both fall within the normal range. If Man A did the test again, he might get a result of 275 – a variation from the first result, but still within the normal range.
Men experience a slow decline in testosterone of about 1% per year from the age of 30, but among men of a given age, testosterone levels can vary a lot. Some men will experience symptoms of low testosterone; many/most do not.
More:
- Understanding aging and testosterone
- Andropause – Causes, Symptoms, Treatment, Diagnosis
- Too Much Testosterone May Be Unhealthy for Older Men – MedicineNet
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