Egg Nutrition Center Blog

Are Vitamin D Levels Over-Screened and Supplements Over-Prescribed?


Skeptics advocate for caution until large-scale studies in progress on vitamin D supplementation are completed.

Vitamin D is essential for calcium absorption and bone health, as summarized by the Institute of Medicine (IOM, 2011).  Moreover, vitamin D is currently being evaluated for a wide-range of health benefits. At this time,

“Many primary care clinicians now include blood tests to measure vitamin concentrations as part of routine laboratory work and recommend vitamin D supplements, often at high doses, to their patients for possible prevention of cancer, cardiovascular disase (CVD), diabetes, autoimmune disorders, cognitive decline, and other conditions.” (Manson and Bassuk, 2015)

In response to these trends, Dr. JoAnn Manson, an expert on the Institute of Medicine’s panel on recommended intakes for calcium and vitamin D, along with colleague Dr. Shari Bassuk, expressed their viewpoint cautioning against widespread vitamin D screening and high-level supplementation in the Journal of the American Medical Association (Manson and Bassuk, 2015).

While acknowledging “dissent from some individual experts” and “lack of consensus on the definition of optimal 25(OH)D concentrations…”, these experts noted that

“When there is uncertainty about whether supplementation is warranted, the usual medical principle is to err on the side of caution and to avoid excess.”

What does vitamin D have to do with eggs? As noted in the IOM report:

“There are a few naturally occurring food sources of vitamin D. These include fatty fish, fish liver oil, and egg yolk.”

More specifically, a medium egg contains 10% of the daily value of vitamin D. Note that vitamin D is fat soluble and therefore found in the egg yolk.

Expert viewpoints from Manson and Bassuk support conclusions stated in an Institute of Medicine brief:

“Scientific evidence indicates that calcium and vitamin D play key roles in bone health. The current evidence, however, does not support other benefits for vitamin D or calcium intake. More targeted research should continue. Higher levels have not been shown to confer greater benefits, and in fact, they have been linked to other health problems, challenging the concept that “more is better.”

Until research findings from current supplementation trials are evaluated, these two experts advocate for caution with respect to supplemental vitamin D.


Reference Citations

Institute of Medicine. “Dietary Reference Intakes for Calcium and Vitamin D.” Washington, DC: The National Academies Press. 2011.

Manson, JE and SS Bassuk. “Vitamin D research and clinical practice: At a crossroads.” JAMA 2015;313(13):1311-1312.

Institute of Medicine. “Report Brief: Dietary Reference Intakes for Calcium and Vitamin D” November 2010.


Views expressed by the author may not be those of the Egg Nutrition Center.

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Author: Barbara Lyle, Ph.D.