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Protein

Also: dietary protein
Last scientific update: jun 2026

Protein is a building block made of amino acids that your body needs for muscles, bones, hormones and repair. As you age you need relatively more protein to preserve muscle mass.

Protein at a glance

WorksYes, for preserving muscleStrong
How much1.2 to 1.6 g per kg in older adults
SafeYes, also for healthy kidneysStrong
SourceMeat, dairy, legumes, fish

Enough protein is essential to preserve muscle mass as you age, and it is safe for healthy kidneys.

24 studies4 answersupdated jun 2026
Evidence per claim
Enough protein helps preserve muscle mass, especially in older adults
View evidence →
Strong
Too little protein raises the risk of fractures
View evidence →
Moderate
Does not harm healthy kidneys
View evidence →
Strong
May support immunity later in life
View evidence →
Preliminary
Practical use

For whom

Older adults, people who train, and those recovering from illness or surgery.

Not for whom

With advanced kidney disease only after consulting a doctor.

Usual dose

For older adults about 1.2 to 1.6 grams per kilo per day, spread across meals.

Key caveats

Works best together with strength training. Combine animal and plant sources.

What we know, and don't

Known

Enough protein plus training preserves muscle mass
Spread intake across the day
Safe with healthy kidneys

Not yet

The exact optimum per person
Whether very high intake adds more
The animal versus plant difference long term
Common misconceptions
"Protein harms your kidneys."
Not shown. Not in healthy kidneys at normal amounts.Strong evidence
"More protein automatically means more muscle."
Incomplete. Only together with strength training.Moderate evidence
"Protein is mainly for bodybuilders."
False. Older adults actually need relatively more.Moderate evidence
How Protein connects
Conditions
Related
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Data sources

Wikidata Q21296145 · MeSH D004045

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