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Related Experiment Video

Updated: Jun 4, 2026

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data

Published on: December 9, 2015

High-dose vitamin D: helpful or harmful?

Karen E Hansen¹

¹Rheumatology Division, University of Wisconsin School of Medicine and Public Health, Room 4124 MFCB, 1685 Highland Avenue, Madison, WI 53705-2281, USA. keh@medicine.wisc.edu

Current Rheumatology Reports

|March 4, 2011

Summary

This summary is machine-generated.

Vitamin D insufficiency is common if 30 ng/mL is optimal. However, new research suggests lower levels may be sufficient, questioning the necessity of higher vitamin D levels for bone health.

Related Experiment Videos

Last Updated: Jun 4, 2026

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data

A Method of Trigonometric Modelling of Seasonal Variation Demonstrated with Multiple Sclerosis Relapse Data

Published on: December 9, 2015

Area of Science:

Endocrinology
Nutritional Science
Bone Health

Background:

The definition of optimal serum 25-hydroxyvitamin D [25(OH)D] levels for skeletal health remains debated.
A common threshold for vitamin D sufficiency is 30 ng/mL, suggesting widespread insufficiency.
Recent evidence challenges this threshold, proposing lower levels may be adequate.

Purpose of the Study:

To evaluate the current evidence regarding the optimal serum 25(OH)D levels for skeletal health.
To critically assess the widely accepted threshold of 30 ng/mL for vitamin D sufficiency.
To investigate the impact of high-dose vitamin D supplementation on bone health outcomes.

Main Methods:

Comprehensive analysis of existing research studies on vitamin D levels and bone health.
Review of a randomized, placebo-controlled trial on high-dose vitamin D therapy.
Examination of studies assessing the effects of vitamin D on parathyroid hormone and bone resorption markers.

Main Results:

The Institute of Medicine concluded that 20 ng/mL 25(OH)D is sufficient for nearly all individuals.
High-dose vitamin D supplementation in one trial increased fractures and falls.
High-dose vitamin D did not improve bone resorption markers in individuals with baseline 25(OH)D levels below 32 ng/mL.

Conclusions:

The necessity of serum 25(OH)D levels of 30 ng/mL or greater for all individuals is questionable.
Lower vitamin D levels may be adequate for maintaining bone health in many adults.
Further research is needed to establish personalized optimal vitamin D levels.