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Current ref range is based on samples from the early 2000s
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Just because the higher end might has been over 1000 doesn’t mean it’s safe for everybody
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It’s discussed highly controversially if T levels in fact have declined or not
‚Several European studies have reported declines in sperm counts over the last 50 years (e.g., [2,3], which indirectly imply changes in testosterone levels, but the reports have lacked consistency, with other studies from the same countries reporting no changes [4] or increases in sperm counts [5]. Studies in the United States have been slightly more consistent, reporting either no changes [6] or increasing sperm counts [7] which in turn imply no changes or increasing levels of serum testosterone levels in American men. This inference, however, is contradicted by a study in American men reporting a decrease in men’s testosterone levels of 1.2% per year [8].
One inference from the increase in FWH ratios is that testosterone levels have increased in American men over the last 120 years. These findings are in agreement with those studies reporting on increased sperm counts [5,7] and are not necessarily in conflict with a previous study that directly measured testosterone levels in males beginning at 45 years of age [8]. While the data from that study support the conclusion that testosterone levels have declined, that conclusion needs to be tempered with the fact that the men in that study were mainly beyond typical reproductive age, and may in fact have not experienced such declines from their peak reproductive years by the time they were tested.‘