Vitamin D Part 2: Good for more than just your bones?

Can you really sit on your couch, pop vitamin D pills, and shave seconds off your 5k? Touted as a miracle cure-all, vitamin D is claimed to slash cancer and infection risks while boosting mood, cognition, and athletic performance. But does upping your vitamin D really make you healthier and happier? In this episode, we’ll follow the epidemiologic evidence—from clues in petri dishes through randomized trials. Along our journey, we’ll encounter chocolate-fueled Nobel Prizes, rock stars, pasty Brits, and a tangled mess of promiscuous variables.

Statistical topics
• ecological studies
• ecological fallacy
• correlation is not causation
• observational studies
• statistical adjustment
• confounding
• randomized trials
• factorial design
• post-hoc analyses
• subgroup analyses

Methodologic morals
• “Variables with too many entanglements make observational studies a fool’s game.”
• “If your intervention works only when you torture your data, it’s probably a false confession.”

Citations

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