Vitamin D for Prevention of Disease Save

JAMA has published a clinical guideline on the use of vitamin D to prevent disease in children and adults. Guideline committee experts, included adult and pediatric endocrinology, internal medicine, obstetrics/gynecology, nutrition, and epidemiology) advise that healthy nonpregnant persons can usually meet the dietary reference intake (DRI) of vitamin D 600 IU/d for ages 19 to 70 years and 800 IU for ages 70 to 74 years without supplementation, as dietary sources of vitamin D a plentiful.  The showed greater concern for people with low socioeconomic status and children. 

Main Takeaways

• Additional empirical vitamin D (without testing for 25-hydroxyvitamin D (25[OH]D) levels) should be considered for: 
  • Children aged 1 to 18 years, to prevent nutritional rickets and potentially lower risk of respiratory tract infections (RTIs). 
  • Adults aged 75 years or older, to potentially lower risk of mortality. 
  • Pregnant women, to potentially lower risk of preeclampsia, intrauterine mortality, preterm birth, small-for-gestational-age birth, and neonatal mortality. 
  • Adults with prediabetes, to potentially decrease risk of progression to diabetes. 
• Routine screening of serum 25(OH)D levels in healthy children and adults is not recommended 
• Healthy people should consume the DRI (600 IU for ages 1-70 years; 800 IU for ages 70-74 years).

Epidemiologic studies suggest lower vitamin D levels may be associated with increased risk of RTIs, cardiovascular disease, malignancy, and metabolic disorders and increased mortality in the elderly (>75 yrs) 

There is no consensus on a vitamin D value below which people should be offered vitamin D supplementation.In 2021, the US Preventive Services Task Force reported that there was insufficient evidence to recommend routine screening of asymptomatic adults for vitamin D deficiency.

For adults aged 75 years or older, a meta-analysis of 25 RCTs (n = 49 879) suggested an association of decreased all-cause mortality with vitamin D supplementation (average dose, 900 IU/d; RD). Yet, other meta-analyses (16 RCTs) of primarily community-dwelling adults older than 75 years showed no effect on fracture rates.

In a meta-analysis of 10 RCTs in people with prediabetes, vitamin D supplementation in addition to lifestyle interventions suggested a decreased progression to type 2 diabetes, without reductions in all-cause mortality or cardiovascular events.

Benefits and Harms

Vitamin D supplements are inexpensive and generally safe, if taken at the recommended amounts. The global prevalence of hypovitaminosis D is high, especially amongst children. The incidence of nutritional rickets is rising (24 per 100 000 patient-years in North America, Australia, and Europe). Most guidelines focus on vitamin D supplementation for children aged 1 to 18 years because of a clear benefit in prevention of growth impairment and possible prevention of lower risk of respiratory tract infections (RTIs). Similarly, the guideline advises vitamin D to decrease all-cause mortality in adults aged 75 years or older. The guideline panel suggests that empirical vitamin D may be beneficial during pregnancy, and in those with prediabetes (to reduce risk of progression to diabetes).