Effect of Vitamin D supplementation to reduce respiratory infections in children and adolescents in Vietnam: A randomized controlled trial
Influenza and other Respiratory Virsus https://doi.org/10.1111/irv.12615
Mark Loeb Anh Duc Dang Vu Dinh Thiem Vitheya Thanabalan Biao Wang Nguyen Binh Nguyen Hung Thi Mai Tran Tan Minh Luong … See all authors
- This trial analyzed the reduction from day one of supplementation
- It is obvious from their graphs that there was no benefit until months later
- Previous studies have found that 2-6 months are needed to restore vitamin D levels
Notes on increased benefits
- 14,000 IU will provide a much bigger benefit to the children who weigh less – but body weight was ignored by this study
- A much bigger benefit will result from gut-friendly Vitamin D (more bio-available)
- A loading dose of vitamin D will start the benefits in 4 days instead of 4 months
- Common cold prevented and treated by Vitamin D, Vitamin C, Zinc, and Echinacea – review April 2018
- Reduction in Cold and Flu with Vitamin D
Background: It is uncertain whether vitamin D can reduce respiratory infection.
Objective: To determine whether vitamin D supplementation reduces influenza and other upper viral respiratory tract infections.
Methods: A total of 1300 healthy children and adolescents between the ages of 3 and 17 years were randomized to vitamin D (14 000 U weekly) or placebo for 8 months in Vietnam. The primary outcome was reverse transcriptase (RT)‐PCR–confirmed influenza infection, and the coprimary outcome was multiplex PCR–confirmed non‐influenza respiratory viruses. Participants, caregivers, and those assessing outcomes were blinded to group assignment.
Results: A total of 650 children and adolescents were randomly assigned to vitamin D and 650 to placebo. The mean baseline serum 25‐hydroxyvitamin D levels were 65.7 nmol/L and 65.2 nmol/L in the intervention and placebo groups, respectively, with an increase to 91.8 nmol/L in the vitamin D group and no increase, 64.5 nmol/L, in the placebo group. All 1300 participants randomized contributed to the analysis. We observed RT‐PCR–confirmed influenza A or B occurred in 50 children (7.7%) in the vitamin D group and in 43 (6.6%) in the placebo group (hazard ratio [HR]: 1.18, 95% CI: 0.79‐1.78). RT‐PCR–confirmed non‐influenza respiratory virus infection occurred in 146 (22.5%) in the vitamin D group and in 185 (28.5%) in the placebo group (hazard ratio [HR]: 0.76, 95% CI: 0.61‐0.94). When considering all respiratory viruses, including influenza, the effect of vitamin D in reducing infection was significant, HR: 0.81, 95% CI: 0.66‐0.99.
Conclusion: Vitamin D supplementation did not reduce the incidence of influenza but moderately reduced non‐influenza respiratory viral infection.