Modest effects of dietary supplements during the COVID-19 pandemic: insights from 445 850 users of the COVID-19 Symptom Study app
BMJ nutrition, prevention & health 2021, 4 (1): 149-157
Panayiotis Louca, Benjamin Murray, Kerstin Klaser, Mark S Graham, Mohsen Mazidi, Emily R Leeming, Ellen Thompson, Ruth Bowyer, David A Drew, Long H Nguyen, Jordi Merino, Maria Gomez, Olatz Mompeo, Ricardo Costeira, Carole H Sudre, Rachel Gibson, Claire J Steves, Jonathan Wolf, Paul W Franks, Sebastien Ourselin, Andrew T Chan, Sarah E Berry, Ana M Valdes, Philip C Calder, Tim D Spector, Cristina Menni
Note that US, which takes larger doses of vitamin D, had a 25% reduction in COVID-19
Suspect that those taking 4,000 IU daily had a 70% reduced risk of COVID-19
Note: this survey defined supplementation as " >3 times a week for at least 3 months"
The very popular and effective Vitamin D dosing schedules of
once a week,
once a month
would not have been detected by this survey
- As of Nov 25, 2022, the VitaminDWiki COVID page had: 19 trial results, 37 meta-analyses and reviews, Mortality studies see related: Governments, HealthProblems, Hospitals, Dark Skins, 26 risk factors are ALL associated with low Vit D, Recent Virus pages Fight COVID-19 with 50K Vit D weekly Vaccines Take lots of Vitamin D at first signs of COVID 116 COVID Clinical Trials using Vitamin D (08/2022)
5 most-recently changed Virus entries
Global (mainly UK) data from abstract in tabular form
|omega-3 fatty acids||12%|
Objectives: Dietary supplements may ameliorate SARS-CoV-2 infection, although scientific evidence to support such a role is lacking. We investigated whether users of the COVID-19 Symptom Study app who regularly took dietary supplements were less likely to test positive for SARS-CoV-2 infection.
Design: App-based community survey.
Setting: 445 850 subscribers of an app that was launched to enable self-reported information related to SARS-CoV-2 infection for use in the general population in the UK (n=372 720), the USA (n=45 757) and Sweden (n=27 373).
Main exposure: Self-reported regular dietary supplement usage (constant use during previous 3 months) in the first waves of the pandemic up to 31 July 2020.
Main outcome measures: SARS-CoV-2 infection confirmed by viral RNA reverse transcriptase PCR test or serology test before 31 July 2020.
Results: In 372 720 UK participants (175 652 supplement users and 197 068 non-users), those taking probiotics, omega-3 fatty acids, multivitamins or vitamin D had a lower risk of SARS-CoV-2 infection by 14% (95% CI (8% to 19%)), 12% (95% CI (8% to 16%)), 13% (95% CI (10% to 16%)) and 9% (95% CI (6% to 12%)), respectively, after adjusting for potential confounders. No effect was observed for those taking vitamin C, zinc or garlic supplements. On stratification by sex, age and body mass index (BMI), the protective associations in individuals taking probiotics, omega-3 fatty acids, multivitamins and vitamin D were observed in females across all ages and BMI groups, but were not seen in men. The same overall pattern of association was observed in both the US and Swedish cohorts.
Conclusion: In women, we observed a modest but significant association between use of probiotics, omega-3 fatty acid, multivitamin or vitamin D supplements and lower risk of testing positive for SARS-CoV-2. We found no clear benefits for men nor any effect of vitamin C, garlic or zinc. Randomised controlled trials are required to confirm these observational findings before any therapeutic recommendations can be made.