Some researchers believe that male hormones vary with the seasons. A 2003 study found that the testosterone levels of men in one Norwegian town bottomed out in summer and reached a high in late fall. A study of Danish men found similar seasonal variations (on a slightly different schedule). If these rhythms are real, they might have to do with sun exposure, summer workouts, or winter weight-gain. But studies done in sunny San Diego and snowy Boston failed to replicate the Scandinavian findings. In a 2012 review, urologists at Baylor College of Medicine in Houston concluded that some “evidence exists to support the notion” of seasonal cycles but cautioned that more research was needed.
Some, semi-common conditions that affect a good portion of society, and more who are non optimal excercisers: methylation problems (active folate, B12, b6 issues pyrroles (zinc, active b6, gla and some magnesium) (see Walsh protocols for a wide range of conditions from variouse malfunction, including sulphication issues, includes methylation) these are issues common in autism spectrum disorders, with Asperger’s being part of the disorder, I suspect trials on University students that be skewed by this), nor-adrenalin, copper vitamin C, iron or zinc and other issues, and people with ATP dysfunction, such as from the virus associated with chronic fatigue. Either a supplement addresses issues, or the underlying physiology might have to run smoothly to maximise it’s affect.