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Research

Revisiting Vitamin D Guidelines

In June of 2024, the Endocrine Society, influenced by a substantial body of research conducted in recent years, published new clinical practice guidelines for the testing and supplementation of Vitamin D for the prevention of disease. These new recommendations included limiting vitamin D supplementation beyond the daily recommended intake to specific risk groups and advised against routine 25-hydroxyvitamin D [25(OH)D] testing in healthy individuals.

In a new review article in the journal, Endocrine Practice, Michael Holick, PhD, MD, professor of medicine, pharmacology, physiology & biophysics and molecular medicine at Boston University Chobanian & Avedisian School of Medicine, compares and contrasts the 2024 Endocrine Society’s Clinical Guidelines on Vitamin D with those he helped design in 2011.

“The 2011 guidelines provided clinicians with guidance for how to evaluate and treat patients with vitamin D deficiency and prevent recurrence, whereas the 2024 guidelines made recommendations for the general healthy population for skeletal and extra skeletal health benefits of vitamin D. I believe this will cause great confusion for physicians and health care professionals as to how to determine if their patient who is at risk for vitamin D deficiency is vitamin D deficient since screening children and adults for their vitamin D status is not recommended in the new guidelines,” explains Holick.

Among the major differences:

• The 2011 Guidelines provided physicians and health care professionals with guidance for when to evaluate a patient for their vitamin D status while the 2024 Guidelines do not.
• The 2011 Guidelines provided health care professionals with information on how much vitamin D is required to treat and prevent vitamin D deficiency in all age groups. The 2024 Guidelines recommends vitamin D supplementation as proposed by the Institute of Medicine in 2010. However, the 2024 Guidelines only put forward the amount of vitamin D needed for anyone one year and older and provides no information for younger infants.
• While the 2024 Guidelines acknowledge that increased vitamin D supplementation with a daily average intake of 2500 IUs may be of value in reducing risk of poor birth outcomes including preeclampsia, preterm births, small-for-gestational age births, neonatal mortality and cesarean section, it does not recommend monitoring vitamin D status in pregnant women and doesn’t propose increased vitamin D intake above 600 IUs daily that is the dietary reference intakes for all adults.

According to Holick, the 2024 Guidelines ignored association studies and other studies and relied on randomized controlled trials, most of which were not placebo-controlled, for their recommendations. “As a result, they do not provide guidance for the many healthful benefits of vitamin D including: reducing cancer mortality by more than 25%; the incidence of metastatic and fatal cancer by 38%; autoimmune disorders by 39%, including type 1 diabetes by 88%; advancement of prediabetes to type 2 diabetes by 76%, peripheral vascular disease by 88% and lowering risk of respiratory tract infections by 58%. In terms of COVID 19 infection, hospitalizations and mortality was reduced by as much as 74%, 22% and 45% respectively, and accelerating COVID positive patients to COVID negativity by 66%; reducing risk of pre-term birth by 62% and preeclampsia and need for a cesarean section by more than 50%,” he adds.