Overview
What is COVID-19?
What are the main signs and symptoms of COVID-19?
How is COVID-19 diagnosed?
What are some of the main medical treatments for COVID-19?
Have any supplements been studied for COVID-19?
How could diet affect COVID-19?
Are there any other treatments for COVID-19?
What causes COVID-19?
Examine Database: COVID-19
Research FeedRead all studies
Vitamin D supplementation during COVID-19 treatment among individuals with a deficiency
In this meta-analysis of 9 randomized controlled trials including 870 participants with a vitamin D deficiency, vitamin D supplementation during COVID-19 treatment reduced mortality compared to a placebo, although the strength of the evidence was limited.
Low vitamin K levels associated with worse COVID-19 outcomes
High-dose vitamin D during hospitalization for COVID-19
Can a multistrain probiotic supplement affect COVID-19 recovery?
Echinacea syrup for COVID-19?
Frequently asked questions
What is long COVID?
What about zinc supplementation and COVID-19?
Which micronutrients can be used to prevent and treat SARS-CoV-2?
How does good hygiene reduce the risk of disease?
References
Examine Database References
- COVID-19 Severity - Shaun Sabico, Mushira A Enani, Eman Sheshah, Naji J Aljohani, Dara A Aldisi, Naif H Alotaibi, Naemah Alshingetti, Suliman Y Alomar, Abdullah M Alnaami, Osama E Amer, Syed D Hussain, Nasser M Al-DaghriEffects of a 2-Week 5000 IU versus 1000 IU Vitamin D3 Supplementation on Recovery of Symptoms in Patients with Mild to Moderate Covid-19: A Randomized Clinical TrialNutrients.(2021 Jun 24)
- COVID-19 Severity - Marta Entrenas Castillo, Luis Manuel Entrenas Costa, José Manuel Vaquero Barrios, Juan Francisco Alcalá Díaz, José López Miranda, Roger Bouillon, José Manuel Quesada Gomez"Effect of calcifediol treatment and best available therapy versus best available therapy on intensive care unit admission and mortality among patients hospitalized for COVID-19: A pilot randomized clinical study"J Steroid Biochem Mol Biol.(2020 Oct)
- COVID-19 Severity - Igor H Murai, Alan L Fernandes, Lucas P Sales, Ana J Pinto, Karla F Goessler, Camila S C Duran, Carla B R Silva, André S Franco, Marina B Macedo, Henrique H H Dalmolin, Janaina Baggio, Guilherme G M Balbi, Bruna Z Reis, Leila Antonangelo, Valeria F Caparbo, Bruno Gualano, Rosa M R PereiraEffect of a Single High Dose of Vitamin D3 on Hospital Length of Stay in Patients With Moderate to Severe COVID-19: A Randomized Clinical TrialJAMA.(2021 Mar 16)
- Need for mechanical ventilation - Yang Y, Sun W, Yang F, Zhang G, Li X, Sun S, Xing YTherapeutic effects of vitamin D supplementation on COVID-19 aggravation: a systematic review and meta-analysis of randomized controlled trials.Front Pharmacol.(2024)
- Need for mechanical ventilation - Zhu L, Zhang Y, Li X, Zou X, Bing P, Qi M, He BVitamin D supplementation for managing COVID-19 in patients with vitamin D deficiency: a systematic review and meta-analysis of randomised controlled trials.BMJ Open.(2025 Mar 26)
- Length of hospitalization - Ghoreshi ZA, Charostad J, Arefinia N, Nakhaie M, Rezaei Zadeh Rukerd M, Salajegheh FEffect of vitamin D supplementation on clinical outcomes in adult patients with COVID-19: A GRADE-assessed systematic review and meta-analysis of randomized controlled trials.Pharmacol Res Perspect.(2024 Sep 3)
- Length of hospitalization - Sartini M, Del Puente F, Carbone A, Schinca E, Ottria G, Dupont C, Piccinini C, Oliva M, Cristina MLThe Effect of Vitamin D Supplementation Post COVID-19 Infection and Related Outcomes: A Systematic Review and Meta-Analysis.Nutrients.(2024 Nov 5)
- COVID-19 Severity - Suma Thomas, Divyang Patel, Barbara Bittel, Kathy Wolski, Qiuqing Wang, Anirudh Kumar, Zachary J Il'Giovine, Reena Mehra, Carla McWilliams, Steve E Nissen, Milind Y DesaiEffect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulatory Patients With SARS-CoV-2 Infection: The COVID A to Z Randomized Clinical TrialJAMA Netw Open.(2021 Feb 1)
- COVID-19 Severity - Saeidreza JamaliMoghadamSiahkali, Besharat Zarezade, Sogol Koolaji, SeyedAhmad SeyedAlinaghi, Abolfazl Zendehdel, Mohammad Tabarestani, Ehsan Sekhavati Moghadam, Ladan Abbasian, Seyed Ali Dehghan Manshadi, Mohamadreza Salehi, Malihe Hasannezhad, Sara Ghaderkhani, Mohsen Meidani, Faeze Salahshour, Fatemeh Jafari, Navid Manafi, Fereshteh GhiasvandSafety and effectiveness of high-dose vitamin C in patients with COVID-19: a randomized open-label clinical trialEur J Med Res.(2021 Feb 11)
- COVID-19 Severity - Hamed Valizadeh, Samaneh Abdolmohammadi-Vahid, Svetlana Danshina, Mehmet Ziya Gencer, Ali Ammari, Armin Sadeghi, Leila Roshangar, Saeed Aslani, Abdolreza Esmaeilzadeh, Mahnaz Ghaebi, Sepehr Valizadeh, Majid AhmadiNano-curcumin therapy, a promising method in modulating inflammatory cytokines in COVID-19 patientsInt Immunopharmacol.(2020 Dec)
- COVID-19 Severity - Papadaki A, Coy EM, Anastasilakis DA, Peradze N, Mantzoros CSThe role of plant-based dietary patterns in reducing COVID-19 risk and/or severity in adults: A systematic review and meta-analysis of observational studies.Clin Nutr.(2024 Jul)