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mind & bodyanalysisScienceDaily

Eating less protein could slow aging, review of 350 studies finds

from ScienceDaily

A major review of more than 350 studies suggests that eating less protein could slow aging, improve metabolic health, and potentially extend lifespan, challenging the widespread belief that more protein is always better. Researchers warn that many sedentary adults may be consuming too much protein, while emphasizing that individual needs depend on age and physical activity.

explained

Proteins are essential nutrients for the human body. They are one of the constituents of body tissue and also serve as a fuel source. As fuel, proteins have the same energy density as carbohydrates: 17 kJ (4 kcal) per gram. From a nutritional perspective, the defining characteristic of protein is its amino acid composition. Protein content in foods is commonly measured based on nitrogen content, as nitrogen is a fundamental component of amino acids.

Proteins are polymer chains made of amino acids linked by peptide bonds. During human digestion, proteins are broken down in the stomach into smaller polypeptide chains via hydrochloric acid and protease actions. This is crucial for the absorption of the essential amino acids that cannot be biosynthesized by the body.

From Wikipedia: Protein (nutrient) (CC BY-SA 4.0) ↗ · text CC BY-SA 4.0
how it works

Protein-rich diets switch on growth pathways such as mTOR and IGF-1, which build tissue but are also tied to faster cell ageing in animal studies. Eating less protein dials those pathways down and appears to improve how the body handles sugar and fat.

so what

Protein is hyped in supplements and snacks, so the finding is a useful check. The best amount depends on age and activity, and the review does not say that everyone should cut back.

fun fact

Protein is the only macronutrient made of nitrogen-containing amino acids, nine of which humans must get from food.

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