Monkeys that eat fewer calories over many years stay more active as they age, while monkeys that eat normally become much less active over time.
See the scientific wording
Long-term calorie restriction prevents the age-related decline in physical activity in rhesus monkeys, as demonstrated by stable accelerometer-measured activity levels over 18 years compared to a 30–40% decline in control animals.
Correlational — new studies may shift this
Randomized trialsOne low-scoring study links this claim to the outcome, but causation is not established.
What the research says
1 study reviewedSupporting (1)
Cohort StudyAnimal2013
Monkeys that ate fewer calories stayed just as active as they got older, while monkeys eating normally became much less active. So, eating less helped them keep moving longer.
Contradicting (0)
No contradicting studies found yet
That doesn't mean it's settled — it just means no study has tested the opposite.
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Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study
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Monkeys that eat fewer calories over many years stay more active as they age, while monkeys that eat normally become much less active over time.
Evidence from Studies
Supporting (1)
Community contributions welcome
Monkeys that ate fewer calories stayed just as active as they got older, while monkeys eating normally became much less active. So, eating less helped them keep moving longer.
1 study stuck in processing — a maintainer can requeue it.
Contradicting (0)
Community contributions welcome
1 study has been processing far longer than a normal run. The pipeline may be stuck — a maintainer can requeue it, and the results will appear here once it finishes.
Score Breakdown
No multi-axis breakdown available yet. The overall Pro / Against score above is the best signal.
- No clinical evidence is available; the score reflects mechanistic plausibility only.
What Would Prove This
Per GRADE and EBM methodology, here is what ideal scientific evidence would look like to definitively prove or disprove this claim, ordered from strongest to weakest.
Systematic Review of Long-Term Calorie Restriction Effects on Physical Activity in Non-Human Primates
Population: Rhesus monkeys; Intervention: Long-term calorie restriction (≥15% reduction from ad libitum intake); Comparator: Ad libitum-fed controls; Outcome: Accelerometer-measured physical activity over ≥15 years; Duration: 18+ years.
Randomized Controlled Trial of Calorie Restriction vs Ad Libitum Feeding on Physical Activity in Aging Rhesus Monkeys
Population: Healthy adult rhesus monkeys; Intervention: Calorie restriction (25–30% reduction); Comparator: Ad libitum feeding; Outcome: Daily accelerometer counts; Duration: 18 years; Design: Randomized, blinded outcome assessors.
Prospective Cohort Study of Calorie Intake and Physical Activity Trajectories in Aging Rhesus Monkeys
Population: Cohort of rhesus monkeys followed from adulthood to old age; Intervention: Natural variation in calorie intake; Comparator: High vs low intake groups; Outcome: Annual accelerometer measurements; Duration: 18+ years; Design: Observational, no randomization.
Longitudinal Study of Accelerometer-Derived Activity in Calorie-Restricted vs Control Rhesus Monkeys Over 18 Years
Population: Rhesus monkeys; Intervention: Calorie restriction (exact % unspecified); Comparator: Control group fed ad libitum; Outcome: Annual accelerometer counts; Duration: 18 years; Design: Non-randomized, longitudinal observation.
Expert Consensus on the Role of Calorie Restriction in Preserving Physical Activity in Aging Non-Human Primates
Delphi panel or expert review by primatologists and gerontologists synthesizing long-term primate studies to form a consensus on calorie restriction effects.