Theodore E. Woodward award. The evolution of obesity: insights from the mid-Miocene.
Level 5 - mechanism / opinion, no new human data
Narrative review and evolutionary hypothesis with no original empirical human data.
What was done
The authors reviewed evolutionary, genetic, and metabolic hypotheses regarding two ancestral primate loss-of-function mutations: the loss of vitamin C synthesis (L-gulono-lactone oxidase mutation in the late Eocene) and uricase silencing (mid-Miocene). They synthesized these genetic events with mechanisms of oxidative stress and fructose metabolism to evaluate Neel's thrifty gene hypothesis.
What was found
The abstract reports no empirical data or quantitative measurements. It describes a theoretical model wherein ancestral mutations causing vitamin C deficiency and elevated uric acid promoted oxidative stress, enhancing fructose-induced fat accumulation as a survival adaptation during Miocene cooling periods. The authors propose that the modern shift toward high intake of added fructose sugars alongside reduced natural fruit consumption interacts with these conserved genetic changes to drive obesity.
Why it matters
The paper provides an evolutionary framework linking specific ancestral pseudogenization events to modern metabolic disease, contextualizing dietary fructose exposure within human evolutionary history.
Limits
This is a theoretical narrative review without new experimental, clinical, or epidemiological data. The abstract provides no quantitative findings or systematic search criteria, and the evolutionary claims rely on mechanistic hypothesis-building rather than direct testing.
Cited by
- supports Humans and great apes share an evolutionary mutation that disabled the uricase gene, allowing fructose to be stored more efficiently as fat.