By Christian Wernstedt
A recent Canadian study has found certain BMI ranges to be more or less correlated with mortality, and quite counter-intuitively the study found that being overweight to mildly obese is the least risky - even somewhat less risky than having a normal BMI.
- Underweight, BMI less than 18.5; relative risk (RR) = 1.73, a significantly increased risk of death
- Overweight, BMI 25-30; RR = 0.83, a significantly decreased risk of death
- Obesity class I, BMI 30-35; RR = 0.95, neutral
- Obesity class II+ , BMI over 35; RR = 1.36, an increased risk of death
So, what's going on here? Should we interpret this study as a license to be flabby?
However, and this is the kicker, once one has controlled for the metabolic syndrome (or put everyone on a paleo diet for 12 months), a different health equation goes into effect, which kicks these Western BMI studies in their soft underbellies.
Hunter-gatherers' BMIs are typically in the lower range of what's considered normal in Western contexts, and their body fat is roughly 10% for males, and 20% for women.
Conversely, what non paleo people in general should do is to rid themselves of the metabolic syndrome by adopting modern paleo principles including some high intensity exercise, and let their BMIs go wherever they need to go in that process. (Fat loss towards aesthetic satisfaction is usually part of the same package, but may require more tweaking.)