Goodrick · Gerontology 1982 · controlled animal feeding study · n=52

Effects of intermittent feeding upon growth and life span in rats.

Cited 159 times in the scientific literature.

Level 5 - mechanism / opinion, no new human data

Animal research (rodent longevity trial)

PubMed 7117847 · doi:10.1159/000212538 · record verified 2026-08-30

What was done

Male Wistar rats were maintained from weaning until death under either ad libitum feeding (AL, n = 28) or every-other-day feeding (EOD, n = 24). The investigators measured lifespan, Gompertzian mortality rates, body weight, and growth parameters.

What was found

The mean lifespan of the EOD group was 83% longer than that of the AL group, with Gompertzian analysis suggesting a retarded rate of aging. The EOD group exhibited reduced body weight and growth rates, but their growth duration was 75% longer than that of the AL group. Significant positive relationships were found between lifespan and growth rate parameters in the AL group, but no significant relationships emerged between lifespan and body weight parameters in the EOD group.

Why it matters

This study provides experimental animal evidence that alternate-day fasting substantially extends lifespan and prolongs the developmental growth phase.

Limits

The study was conducted in a small sample of male laboratory rats (total n = 52), limiting direct translation to females or humans. Absolute lifespan values, exact variance estimates, and specific p-values are not reported in the abstract.

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