The Age Related Decline in Testosterone

Starting around age 30 testosterone levels decrease at a rate of about 1% per year. This may not seem like much but when compounded over many years it can have a significant impact. The reason that testosterone declines is multifactorial and the individual rate of decline is influenced by many factors. Like many things, testosterone is heavily influenced by genetic predisposition. This means that all things equal one man may be more likely than another to have low testosterone levels or a faster rate of decline. Unfortunately, there is not much that can be done about that; everyone’s levels will decline with age but some faster than others. Additionally, many lifestyle (chronic stress, disturbed sleep patterns, etc.) and environmental factors (toxin exposure, pollution, etc.) influence testosterone levels, and the more of those working against you the faster your levels will likely decline. Beyond that, if you have a chronic illness like obesity or diabetes or you take certain medications your testosterone level can also decline at a faster rate. Not to mention that with age, the risk of chronic disease or being on a medication that can interfere with hormone levels becomes much more likely. But let’s say for a moment you won the genetic lottery, your lifestyle is pristine, you have no chronic illnesses, and take no medication. Unfortunately, there are still physiologic changes that will occur with age causing some amount of decline in testosterone levels. Testosterone is made by the Leydig cells in the testes and for testosterone to be produced several signaling molecules must be released in the brain. With age, this signaling cascade can become impaired leading to decreased testosterone production. Similarly, the Leydig cells in the testes themselves can become less efficient at generating testosterone leading to less production. These factors, independently or in combination, with time will result in lower testosterone levels. The reproductive system was designed for the perpetuation of life, not for sustained human optimization, and longer lifespans highlight where it falls short. Testosterone replacement therapy is a solution to the age-related decline in testosterone as well as many secondary issues stemming from hormonal imbalances.