Thanks to Emerald Snow for this commentary.
The one thing that united all the talks in this session: human
variation makes everything more complicated! This session opened up
with a talk by Grazyna Jasienska on breast cancer prevention. She
reviewed the literature showing increased risk of breast cancer when
women have high circulating sex hormones throughout their lifetime.
Physical activity is one way to ameliorate this phenomenon, and the
American Cancer Society recommends physical activity for prevention.
Jasienska argued that there are too many variables at play (timing of
life history events, birth weight, etc.) to have one recommendation
for amount of and frequency of physical activity to be beneficial for
Katie Hinde showed us how it might not be appropriate to
think of one gold standard for human milk and human milk substitutes.
As there is much variation in human milk composition (due to factors
associated with maternal environment, baby’s sex, and more), research
that aims to provide better milk substitutes or evaluate milk may
benefit from keeping these factors in mind.
Kathryn Clancy gave an insightful talk highlighting variation in human female reproductive physiology and how clinicians may use this to “define normalcy” and
provide more healthy family planning, especially for young people.
Alejandra Nunez de la Mora also showed us that in looking at developmental plasticity and resulting outcomes, we have to look at many different variables, at different points in time, to really make helpful conclusions to apply in public health.
We are then lead into the realm of men’s health, with Richard Bribiescas giving us some of the pros and cons of testosterone supplements for healthy men. He
highlights the trade-offs of higher testosterone levels from an evolutionary perspective and urges us to question the high use of this hormone for non-medical purposes (~40-50% in a US sample).