[Fishman343]

Nutritionally I see what you mean and definitely agree, people are taller than they used to be and until recently have lived longer. But all of the benefits a nutritionally diverse and rich diet brings are easily undone (and more) by also consuming enough sugar to become obese. This is why the current generation of obese kids at school have a lower life expectancy than their parents despite better healthcare and nutrition in their early years.

This is why I think that jumping on the "BPA must be the problem!" answer to low count question is a bit ridiculous, especially when people are becoming more unhealthy by the day. People who eat more processed sugary foods and drinks that come in BPA containing packaging are also more likely to be obese and unhealthy too.

Lacking physical work also does not account for all of the weight gain we are seeing at the moment - obesity rates remained stable in the '60s and '70s when we lived similarly lazy lives. (1)

1. http://www.nejm.org/doi/full/10.1056/NEJMsr043743#t=article