Bonus: Vitamin D Part 1 with commentary

About this episode

The episode revisits a deep dive into vitamin D and the origins of the deficiency epidemic, exploring statistical issues and medical guidelines.

While we’re on a short break between seasons, we’re revisiting some of our favorite episodes from Season 1. This week, we’re re-releasing our deep dive into vitamin D and the origins of the so-called deficiency epidemic, with added commentary. Is America really facing an epidemic of vitamin D deficiency? While this claim is widely believed, the story behind it is packed with twists, turns, and some pesky statistical cockroaches. In this episode, we’ll dive into a study on Hawaiian surfers, expose how shifting goalposts can create an epidemic, tackle dueling medical guidelines, and flex our statistical sleuthing skills. By the end, you might wonder if the real deficiency lies in the data. Statistical topics conflicts of interest cut points and thresholds dichotomization incentives in science measurement and classification normal distribution researcher biases standard deviation statistical sleuthing Methodologic morals “Arbitrary thresholds make for arbitrary diseases.” “Statistical errors are like cockroaches: Where there’s one, there’s many.” Note that all blood vitamin D levels discussed in the podcast are 25-hydroxyvitamin D levels given in units of ng/ml. To convert from…

People in this episode

Hosts: Regina Nuzzo, Kristin Sainani

Topics covered

• vitamin D
• deficiency epidemic
• statistical analysis
• medical guidelines
• research biases
• measurement and classification

Keywords

• vitamin D deficiency
• statistical cockroaches
• Hawaiian surfers study
• cut points
• dichotomization
• researcher biases
• normal distribution

Mentioned in this episode

Organizations: Huberman Lab Podcast

Books & works: A Case of Nutritional Osteomalacia in Young Adult

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