Men's testosterone levels have declined from an average in the 700s (~25 nmol/l) to an average of 420 ng/dl (14.5 nmol/l) over the last 50 years. While around half of this decline can be explained by increasing rates of obesity, it is unclear whether the relationship obesity causes low T on its own or whether there is a confounding variable causing both. Non-obese, exercising males have also been found to have experienced a proportionally equivalent drop in T levels. PFAS contamination has also been theorized to be partially responsible for the drop in testosterone levels, but I do not believe that there have been any large scale non-epidemiological studies sufficient to infer causality (someone fact check this please). I also do not believe that it would be responsible for the majority of the decline.

The global drop in testosterone has had negative downstream affects on fertility, virility and mental stability -- and arguably could be a key contributing factor in the rise of misogynistic so-called "alpha male" thought leaders.

This market resolves yes if there is a convincing large scale study or review published by 2028 that proves a definitive causal link between declining testosterone levels and certain epidemiological factors that, when combined, account for 90% or more of the decline in mens testosterone levels.

This market resolves no otherwise.

I will use my best judgement & knowledge of the situation to resolve appropriately.