Research

Hormonal

A low-protein/high-carbohydrate (LPHC) diet or specific restriction of methionine and branched-chain amino acids (BCAAs) extends longevity and improves metabolic health in model organisms and middle-aged humans by suppressing mTORC1 and GH/IGF-1 signaling while promoting autophagy and FGF21 production.

Focus on the source and balance of protein rather than just total grams. Prioritize plant-based proteins and consider reducing methionine-rich animal proteins (like red meat) if you are middle-aged, as this may support longevity pathways. However, ensure adequate protein intake in older age to prevent frailty.

GoodSupportsHIGH confidence
Recent studies show that a reduced protein intake or low-protein/high-carbohydrate diet plays a critical role in longevity/metabolic health. Additionally, specific amino acids (AAs), including methionine or branched-chain AAs (BCAAs), are associated with the regulation of lifespan/ageing and metabolism through multiple mechanisms. Therefore, methionine or BCAAs restriction may lead to the benefits on longevity/metabolic health.
Munehiro Kitada et al. · EBioMedicine · 2019

Why this rating

Strong evidence from multiple animal models and epidemiological human studies, though direct long-term human lifespan data is lacking.

Source

The impact of dietary protein intake on longevity and metabolic health

Munehiro Kitada et al. · EBioMedicine · 2019

DOI 10.1016/j.ebiom.2019.04.005

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DOI resolved against Crossref · corpus check 2026-06-10

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