The longevity space is full of competing claims — Zone 2 vs. HIIT, fasting vs. caloric restriction, carnivore vs. Mediterranean. We score each head-to-head across outcomes that matter: cardiovascular health, metabolic markers, cognitive function, body composition, and longevity evidence.
Each outcome domain is scored 1–10 for each protocol based on the weight of human clinical evidence. A score of 10 represents the strongest available evidence base with large effect sizes. A score of 5 represents a neutral or mixed finding. Scores below 5 indicate evidence of harm or inferior performance on that specific outcome.
The "winner" of each outcome row is the protocol with the higher score. Overall winners are determined by total score across all applicable domains. A "tie" or "both" verdict means the evidence does not support a clinically meaningful difference — choosing based on preference, adherence, or individual response is the appropriate strategy.
All scores are based on RCT evidence where available, with large prospective cohort data used where RCT data is absent or limited. Animal data is not used for scoring. Scores will be updated as major new trials publish. Last comprehensive review: April 2025.
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