Research

Hormonal

Intermittent fasting (IF) and prolonged fasting (PF) are safe and effective interventions that mimic the health benefits of chronic dietary restriction, including reduced inflammation and improved insulin sensitivity, without the severe side effects of continuous caloric restriction.

If you are not diabetic or on insulin, try alternate-day fasting (eating normally one day, restricting to ~500-600 calories the next) or periodic prolonged fasting (water-only for 2+ days, once a month). These methods reduce inflammation and improve insulin sensitivity without the constant hunger of daily dieting. If you have diabetes, consult your doctor before attempting any fasting regimen due to hypoglycemia risks.

ModerateSupportsMEDIUM confidence
PF and IF have few adverse effects... Preliminary studies suggest that PF may also decrease adverse effects of chemotherapy in humans... The health effects of IF in humans have been investigated more extensively... 3 weeks of alternate-day fasting reduces body weight, body fat, and plasma insulin concentrations... while a diet of 500–600 calories on 2 of 7 days per week induces loss of abdominal fat, improves insulin sensitivity, and reduces blood pressure.
Valter D. Longo et al. · Aging Cell · 2015

Why this rating

The paper cites preliminary human clinical studies (e.g., Heilbronn et al., 2005; Harvie et al., 2010) but notes that long-term healthspan effects are not fully known and larger trials are needed.

Source

Interventions to Slow Aging in Humans: Are We Ready?

Valter D. Longo et al. · Aging Cell · 2015

DOI 10.1111/acel.12338

narrative_reviewCited 596×
Read the paper
DOI resolved against Crossref · corpus check 2026-06-10

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