Vitamin D testing and treatment: a narrative review of current evidence.

Endocr Connect · 2019 · PMC6365669 · PMID 30650061

Europe PMC DOI

hedged sentence

—

closest p

—

boldest claim

The sentences

quite significantno p-value reported

As a frequently quoted rough summary, it can be estimated that per intake of about 2.5 μg (100 IU) of vitamin D per day, the serum 25(OH)D concentrations may increase by about 2.5–5 nmol/L but with quite significant variability of such estimates in the literature ( 88 , 91 ).

also in 5,682 other papers

Quoted from the open-access full text in Europe PMC under the licence the publisher applied. The sentence is reproduced exactly as published; the emphasis is ours.