Nutrition May 15, 2026 4 min read

Vitamin D: reference range vs. optimal range

Name: Vitamin D: reference range vs. optimal range
Creator: Maksym Bychenko
Published: 2026-05-15

The lab says you’re “in range,” but is that the same as optimal? A look at what the research suggests for everyday health.

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Written by Maksym Bychenko Head of Marketing, Longetic

Reviewed by longevity experts Oleksandra Zubarchuk, M.Sc. in Clinical Engineering

Updated May 15, 2026

This article is for informational purposes only and is not a substitute for professional medical advice. Read our Medical Disclaimer.

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