While the Pontzer et al (2012) result is interesting, I don’t read too much into it. For women, the difference in PAL is small (and strictly, not significant). The difference is larger for men (Hadza about 25% higher), but there are only 31 men in the sample. Probably more importantly, these populations will differ in many ways, which may affect their BMRs. It certainly doesn’t shift my view from the meta-analysis I linked, and indeed the paper itself says, “It is important to note that this was not an intervention study; we examined habitual TEE, PAL, and body composition in hunter-gatherers and Westerners, but did not examine the effects of imposing increased physical activity on Westerners. Physical activity has important, positive effects on health, and increased physical activity has been shown to play an important role in weight loss and weight-maintenance programs.”
FWIW, I do agree with the conclusion (contrary to what I once believed) that “differences in obesity prevalence between populations result primarily from differences in energy intake rather than expenditure”. The important evidence for me here is that changes in population level obesity over time fail to match changes in physical activity. It doesn’t follow that you personally cannot outrun your fork, and the ACX survey results suggest that at least some people can (as I intend to say on the open thread), although I don’t necessarily recommend trying it.
Thanks. I think I’ve fixed the links now.
While the Pontzer et al (2012) result is interesting, I don’t read too much into it. For women, the difference in PAL is small (and strictly, not significant). The difference is larger for men (Hadza about 25% higher), but there are only 31 men in the sample. Probably more importantly, these populations will differ in many ways, which may affect their BMRs. It certainly doesn’t shift my view from the meta-analysis I linked, and indeed the paper itself says, “It is important to note that this was not an intervention study; we examined habitual TEE, PAL, and body composition in hunter-gatherers and Westerners, but did not examine the effects of imposing increased physical activity on Westerners. Physical activity has important, positive effects on health, and increased physical activity has been shown to play an important role in weight loss and weight-maintenance programs.”
FWIW, I do agree with the conclusion (contrary to what I once believed) that “differences in obesity prevalence between populations result primarily from differences in energy intake rather than expenditure”. The important evidence for me here is that changes in population level obesity over time fail to match changes in physical activity. It doesn’t follow that you personally cannot outrun your fork, and the ACX survey results suggest that at least some people can (as I intend to say on the open thread), although I don’t necessarily recommend trying it.