Fit Body ScienceEvidence-based fitness analysis

In Chinese adults aged 18–64, consuming less than 0.87 grams of animal protein per kilogram of body weight per day is associated with higher bone mineral density, while consuming more than this amount is associated with lower bone mineral density.

See the scientific wording

In Chinese adults aged 18–64, dietary animal protein intake has a curvilinear association with bone mineral density at the lumbar spine, total hip, and whole body, with a positive association below 0.87 g/kg/day and a negative association above this threshold.

Supporting1 study

Correlational — new studies may shift this

Observational

One moderate-quality study links this claim to the outcome, but causation is not established.

What the research says

1 study reviewed

Supporting (1)

Moderate

Contradicting (0)

None

No contradicting studies found yet

That doesn't mean it's settled — it just means no study has tested the opposite.

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Why this might work

When people eat moderate amounts of animal protein, gut bacteria produce compounds that make the body's internal environment slightly more acidic, which helps the intestines absorb more calcium from food. This extra calcium strengthens bones. But when people eat too much animal protein, the gut bacteria produce too many acidic compounds, which forces the body to pull calcium out of bones to balance the acid levels, weakening them over time.

Supported mechanismbased on 1 study

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting study

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