The Claim

Basal metabolic rate has declined over the past century in adult human populations, after adjustment for body mass, age, and sex, as demonstrated across 9,912 individuals in 163 studies, extending beyond the original 30-year analysis window.

Source: Total daily energy expenditure has declined over the last 3 decades due to declining basal expenditure not reduced activity expenditure.

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
44score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Description
1 study reviewed
In plain English

Over the last 100 years, the rate at which the human body burns energy at rest has decreased in adults, even when accounting for differences in body size, age, and sex, based on data from thousands of people across more than 160 studies.

See the scientific wording

A decline in basal metabolic rate over the past century, adjusted for body mass, age, and sex, has been replicated in a separate dataset of 9,912 adults across 163 studies, suggesting this trend extends beyond the 30-year window of the primary analysis.

Why this might work

The body runs cooler than it did a century ago, so it needs less energy to stay warm. This means the cells in organs like the liver and brain burn fewer calories just to keep functioning at rest.

Verified mechanismbased on 1 study

What the research says

1 study
  1. Study: Total daily energy expenditure has declined over the last 3 decades due to declining basal expenditure not reduced activity expenditure.

    Scientists found that, over the last 100 years, people’s bodies have slowly started burning fewer calories while at rest—even when accounting for size, age, and gender. This trend was seen in thousands of people across many studies.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

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Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.