Hunter-gatherers as models in public health.
Level 5 - mechanism / opinion, no new human data
Narrative review and observational synthesis without systematic review methodology
PubMed 30511505 · doi:10.1111/obr.12785
What was done
The authors reviewed recent literature and fossil/archaeological discoveries on health, physical activity, energetics, and diet across hunter-gatherers and other small-scale societies (subsistence farmers, horticulturalists, and pastoralists). The review incorporated supplementary observational data from the Hadza hunter-gatherer population in northern Tanzania.
What was found
Small-scale populations demonstrate longevity approaching that of industrialized populations, with rare metabolic and cardiovascular disease. Obesity prevalence is <5%, and mean body fat percentage is 24% to 28% in women and 9% to 18% in men. Moderate-to-vigorous physical activity exceeds 100 min/day, yet total daily energy expenditures are similar to industrialized populations. Diets are less energy dense and richer in fiber and micronutrients, but are not invariably low-carbohydrate.
Why it matters
These observations challenge assumptions that high physical activity linearly increases total daily energy expenditure, supporting models of constrained metabolic expenditure. They also indicate ancestral human diets were diverse rather than uniformly low in carbohydrates.
Limits
As a narrative review, the paper does not specify systematic search parameters, meta-analytic pooling, or total sample sizes. Comparisons between small-scale societies and industrialized populations are observational and subject to confounding, and the abstract lacks statistical precision estimates.
Cited by
- supports Hunter-gatherer populations typically walked approximately 7 to 10 miles (about 14,000 steps) per day.