New Study Suggests Revising Testosterone Guidelines
Researchers suggest revising the guidelines used to evaluate low testosterone (low-T) to assure proper care. Testosterone deficiency or male hypogonadism is linked to low libido, infertility problems, diabetes and osteoporosis. Also, muscle mass decreases significantly if testosterone levels drop too low.
Testosterone is found in the body in two forms; protein binding which is 98% of total testosterone with the remaining 2% free or non-protein bound. Current guidelines measure total testosterone levels, however researchers from the University of Manchester, UK and the University of Leuven, Belgium suggest that measuring the levels of free testosterone may be more important.
It is the non-binding free testosterone that enters the cells and is responsible for the benefits received of increased testosterone activity. And as men get older total testosterone levels decrease while the binding protein increases. Therefore the levels of free testosterone decrease more than total testosterone.
According to the study, men with low free testosterone levels showed symptoms associated with low-T even though their total testosterone levels were normal. However, men with normal free testosterone did not show symptoms of low-T with lower total testosterone readings. The findings suggest men may fail to get proper treatment based on how tests are administered, which often excludes testing for non-binding free testosterone levels.
This may explain the rash of class action lawsuits recently by patients who believed their treatment for low-T caused cardiac arrest, stroke or other heart-related issues and side effects.
The doctors in the study propose measuring free testosterone in conjunction with total testosterone to ensure proper treatment.