For years, the recommendation has been to get a testosterone value early in the morning because levels start to drop after 10 or 11 a.m. But the data behind that recommendation were drawn from healthy young men. Two recent studies showed little change in blood testosterone levels in men 40 and older over the course of the day. One reported no change in average testosterone until after 2 p.m. Between 2 and 6 p.m., it went down by 13%, a modest amount, and probably not enough to influence diagnosis. Most guidelines still say it’s important to do the test in the morning, but for men 40 and above, it probably doesn’t matter much, as long as they get their blood drawn before 5 or 6 p.m.
Before taking any supplements, at either end of the spectrum, you need to check whether it’s low testosterone that is actually causing the problem. Taking something that you don’t need could potentially cause irreversible issues. For that reason, steroid hormones like DHEA should never be prescribed without having blood tests first. Roked also recommends regular blood monitoring to make sure you’re taking the correct dosage.
Free testosterone (T) is transported into the cytoplasm of target tissue cells, where it can bind to the androgen receptor, or can be reduced to 5α-dihydrotestosterone (DHT) by the cytoplasmic enzyme 5α-reductase. DHT binds to the same androgen receptor even more strongly than testosterone, so that its androgenic potency is about 5 times that of T. The T-receptor or DHT-receptor complex undergoes a structural change that allows it to move into the cell nucleus and bind directly to specific nucleotide sequences of the chromosomal DNA. The areas of binding are called hormone response elements (HREs), and influence transcriptional activity of certain genes, producing the androgen effects.
Testosterone is significantly correlated with aggression and competitive behaviour and is directly facilitated by the latter. There are two theories on the role of testosterone in aggression and competition. The first one is the challenge hypothesis which states that testosterone would increase during puberty thus facilitating reproductive and competitive behaviour which would include aggression. Thus it is the challenge of competition among males of the species that facilitates aggression and violence. Studies conducted have found direct correlation between testosterone and dominance especially among the most violent criminals in prison who had the highest testosterone levels. The same research also found fathers (those outside competitive environments) had the lowest testosterone levels compared to other males.
Let’s do a quick review of what I shared in the introduction to this series. August of last year was a tough month for me, primarily because of a huge and grueling project we were in the midst of here on the site. I was stressed out and my sleeping, healthy eating habits, and workout regimen all suffered. At the end of the month I got my testosterone levels tested and found that my total T was 383 ng/dL and my free T was 7.2 pg/mL – close to the average for an 85-100-year-old man.
Some of these signs and symptoms can be caused by various underlying factors, including medication side effects, obstructive sleep apnea, thyroid problems, diabetes and depression. It's also possible that these conditions may be the cause of low testosterone levels, and treatment of these problems may cause testosterone levels to rise. A blood test is the only way to diagnose a low testosterone level.