New Guidelines Redefine Normal Vitamin D Levels—Who Really Needs Supplements?

Vitamin D supplements continue to be popular, with more people seeking tests to determine their levels. However, experts still debate the optimal amount of vitamin D for good health. New guidelines from the U.S. Endocrine Society have adjusted the recommended threshold for normal vitamin D levels in the blood.

The 2024 U.S. Endocrine Society guidelines lowered the normal vitamin D level from 75 nmol/L to 50 nmol/L. This change reflects ongoing uncertainty about the ideal dose and blood concentration for preventing disease. For most healthy adults, routine supplementation is no longer advised unless a deficiency is suspected.

An article by endocrinologist Vallo Volke in Eesti Arst (2024) supports this approach, stating that adults under 75 do not need regular vitamin D intake or blood tests. The Estonian Health Insurance Fund also discourages including vitamin D tests in standard blood work. However, doctors can still order the test if they believe it is necessary. Supplements are still recommended for specific groups: children, adolescents, pregnant women, and people aged 75 and older. For those over 75, supplementation is advised, but routine testing is not required.

The updated guidelines shift away from widespread vitamin D testing and supplementation for healthy adults. Doctors now have clearer recommendations on when to prescribe supplements or order tests. The focus remains on targeted use for at-risk groups rather than general screening.