To be very clear, these kinds of polygenic scores are incredibly shit predictors of individual traits... HT @anjiolina.bsky.social #GATTACA

Ou, C., Lou, N. M., Maheshka, C., Shi, M., Takemura, K., Cheung B., & Heine, S. J. (in press). Healthy sleep durations appear to vary across cultures. PNAS. osf.io/preprints/ps...

e) Individuals whose sleep duration was closer to their country’s norms reported better health. These findings suggest that the amount of sleep associated with optimal health varies across countries. There isn’t a global standard for healthy sleep durations.

c) A quadratic relation emerged between sleep duration and health in all countries such that both too much sleep and too little sleep was associated with worse health; d) The turning points of these quadratic curves varied significantly between countries.

b) People from countries with longer sleep durations were not healthier than from countries with shorter durations. We replicated this by analyzing national sleep durations from 14 past studies which also revealed no associations with national health.

In a new paper in press at PNAS, we collected data on sleep duration and health from 5000 participants in 20 countries. There were several notable findings: a) First, average sleep durations varied substantially between countries (range = 1.57 hours).