Decision Letter: Effects of Lifelong Testosterone Exposure on Health and Disease Using Mendelian Randomization
July 2020
TLDR Increased free testosterone can lead to stronger bones and less body fat but also higher risks of prostate cancer, hair loss, spine issues, and high blood pressure.
In 2020, a Mendelian randomization study was conducted on 161,268 males from the UK Biobank study to investigate the effects of lifelong increased free testosterone. The study found that increased free testosterone had beneficial effects on increased bone mineral density and decreased body fat. However, it also had adverse effects, including decreased HDL, increased risks of prostate cancer, androgenic alopecia, spinal stenosis, and hypertension. No benefit was observed for type 2 diabetes, cardiovascular or cognitive outcomes. The study concluded that the benefits of long-term increased testosterone should be considered against its adverse effects, notably increased prostate cancer and hypertension. The researchers suggested that well-powered randomized trials are needed to conclusively address the risks and benefits of testosterone treatment on these outcomes.