Two new trials find no link between vitamin D supplements and reduced risk of COVID-19

Two massive medical trials printed by The BMJ at this time present that boosting vitamin D ranges in adults through the SARS-CoV-2 pandemic was not related to safety in opposition to respiratory tract infections or COVID-19.

Vitamin D metabolites have lengthy been acknowledged to help innate immune responses to respiratory viruses and micro organism, and a few research have proven that vitamin D could shield in opposition to respiratory tract infections, notably amongst those that are vitamin D-deficient.

Vitamin D has due to this fact acquired a lot consideration for its potential position in stopping and treating COVID-19, however most research printed to this point are observational and have proven blended outcomes.

The primary trial was carried out within the UK between December 2020 and June 2021 and concerned 6,200 adults (16 years and over) not utilizing vitamin D dietary supplements at enrollment.

Half (3,100 members) have been provided a vitamin D blood take a look at and people discovered to have low vitamin D ranges (2,674; 86%) acquired both 3200 IU/day or 800 IU/day of vitamin D dietary supplements for six months, whereas the opposite half (controls) acquired no take a look at or dietary supplements.

Neither of the vitamin D doses confirmed any impact on identified acute respiratory tract infections or lateral circulation take a look at or RT-PCR-confirmed COVID-19 instances over a six-month follow-up interval. The variety of adversarial occasions was comparable between teams, and no critical adversarial occasion was attributed to review dietary supplements.

The second trial was carried out in Norway between November 2020 and June 2021 utilizing cod liver oil, which incorporates low doses of vitamin D and vitamin A in addition to omega-3 fatty acids.

A complete of 34,741 adults (18-75 years) who weren’t utilizing vitamin D dietary supplements acquired both 5 mL cod liver oil or 5 mL placebo (corn oil) every day for six months. Nearly all of members (86%) who have been examined had enough vitamin D ranges firstly of the examine.

Once more, the researchers discovered no impact of cod liver oil on acute respiratory infections or PCR-confirmed COVID-19, in contrast with placebo. The cod liver oil group had no extra negative effects than the placebo group and solely low-grade negative effects have been reported.

Each trials have notable limitations. For instance, within the UK trial, members randomized to the energetic arms knew they have been taking an energetic drug and virtually half of controls took a vitamin D complement on a minimum of one event through the trial. Within the Norway trial, members have been comparatively younger and wholesome, and most (when examined) had enough vitamin D ranges firstly of the examine.

The findings also needs to be interpreted within the context of a extremely efficient vaccine rolled out throughout each trials.

Nonetheless, each trials had a number of strengths, together with use of RT-PCR swab exams to substantiate infections and excessive ranges of compliance amongst members. The outcomes are additionally in keeping with earlier analysis that discovered no preventive impact of vitamin D on threat of COVID-19.

Collectively, these new outcomes recommend that vitamin D dietary supplements don’t cut back threat of COVID-19 or different acute respiratory infections.

In a linked editorial, Professor Peter Bergman on the Karolinska Institutet in Sweden says vaccination continues to be the simplest method to shield individuals from COVID-19, and vitamin D and cod liver oil supplementation shouldn’t be provided to wholesome individuals with regular vitamin D ranges.

As an alternative, he suggests clinicians might concentrate on threat teams, together with individuals with darkish pores and skin, or pores and skin that’s not often uncovered to the solar, pregnant girls, and aged individuals with power illnesses, who might be examined earlier than supplementation.