Studies analyze diet quality before infection, and use different definitions of diet quality.
Recent:Barh Hao Koyama Wang.
Submit updates/corrections .
Apr 25 |
Diet for COVID-19: real-time meta analysis of 28 studies | |
| Statistically significant lower risk is seen for ICU admission, hospitalization, progression, recovery, cases, and viral clearance. 24 studies from 23 independent teams in 10 countries show statistically significant improvements. Meta ana.. | ||
Feb 20 |
et al., Nutrition Journal, doi:10.1186/s12937-024-00927-3 | Association of dietary inflammatory index and the SARS-CoV-2 infection incidence, severity and mortality of COVID-19: a systematic review and dose-response meta-analysis |
| Systematic review and dose-response meta-analysis of 5 studies with 197,929 participants showing higher SARS-CoV-2 infection risk and COVID-19 severity with higher Dietary Inflammatory Index (DII) scores. The odds of COVID-19 increased 31.. | ||
Jan 31 |
et al., medRxiv, doi:10.1101/2024.01.30.24302040 | Healthy lifestyle for the prevention of post-COVID-19 multisystem sequelae, hospitalization, and death: a prospective cohort study |
| Prospective study of 68,896 UK Biobank participants with COVID-19 showing adherence to a healthy lifestyle prior to infection, characterized by 10 factors including adequate physical activity and sleep, not smoking, and a healthy BMI, was.. | ||
Jan 30 |
et al., medRxiv, doi:10.1101/2024.01.29.24301882 | Possible roles of phytochemicals with bioactive properties in the prevention of and recovery from COVID-19 |
| Survey of 1,583 participants globally showing higher daily intake of vegetables, herbs/spices, and fermented foods/beverages among those who did not contract COVID-19 compared to those who tested positive or suspected they had it. Shorter.. | ||
Nov 30 2023 |
et al., NCT04751669 | Efficacy of Micronutrient Dietary Supplementation in Reducing Hospital Admissions for COVID-19: A Double-blind, Placebo-controlled, Randomized Clinical Trial |
| Estimated 300 patient diet early treatment RCT with results expected soon (estimated completion over 4 months ago). | ||
Nov 9 2023 |
et al., Diseases, doi:10.3390/diseases11040165 | Association of COVID-19 Infection with Sociodemographic, Anthropometric and Lifestyle Factors: A Cross-Sectional Study in an Older Adults’ Population Aged over 65 Years Old |
| 55% fewer cases (p=0.0009). Retrospective 5,197 Greek adults over 65. After adjustment for confounders, COVID-19 infection was independently associated with poor sleep, low physical activity, low Mediterranean diet adherence, living in urban areas, smoking, obesity,.. | ||
Nov 7 2023 |
et al., Nutrients, doi:10.3390/nu16071037 | The Association between Lifestyle Factors and COVID-19: Findings from Qatar Biobank |
| 7% fewer cases (p=0.02). Retrospective 10,000 adults in Qatar, showing higher risk of COVID-19 cases with a modern diet characterized by foods high in refined carbohydrates and saturated fat (e.g. fast food, soft drinks, and dessert). Authors do not analyze COVID.. | ||
Oct 27 2023 |
et al., Clinical Nutrition Research, doi:10.7762/cnr.2023.12.4.283 | Relationship Between Dairy Intake and Hospitalization Risk and Disease Severity in Patients With COVID-19 |
| Retrospective 141 COVID-19 patients showing that higher dairy intake was associated with lower risk of hospitalization. The risk of hospitalization was 31% lower in the highest tertile of dairy intake compared to the lowest, after adjustm.. | ||
Oct 2 2023 |
et al., BMC Nutrition, doi:10.1186/s40795-023-00727-8 | Beneficial role of healthy eating Index-2015 score & physical activity on COVID-19 outcomes |
| Retrospective 68 COVID-19 patients showing higher healthy eating index scores associated with lower risk of moderate vs. mild COVID-19. | ||
Aug 14 2023 |
et al., Jornal de Pediatria, doi:10.1016/j.jped.2023.07.006 | Lifestyle and quality of life in children and adolescents during the covid-19 social distancing period |
| Cross-sectional analysis of 2,574 families in Brazil, showing that pandemic social distancing caused negative changes in exercise, diet, and sleep for children. | ||
Aug 3 2023 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2023.1241016 | Association of dietary intake of polyphenols, lignans, and phytosterols with immune-stimulating microbiota and COVID-19 risk in a group of Polish men and women |
| 70% fewer cases (p=0.09). Dietary analysis of 95 adults in Poland, showing lower risk of COVID-19 with higher intake of polyphenols, lignans, and phytosterols. Results were statistically significant for total phytosterols, secoisolariciresinol, β-sitosterol, matai.. | ||
Jul 31 2023 |
et al., Infection and Drug Resistance, doi:10.2147/idr.s409615 | Improving Nutritional Status Was Associated with Decreasing Disease Severity and Shortening of Negative Conversion Time of PCR Test in Non-ICU Patients with COVID-19 |
| 45% lower severe cases (p=0.06) and 32% improved viral clearance (p=0.03). Retrospective 148 hospitalized COVID-19 patients in China, showing lower severity and faster viral clearance with improved nutrition. | ||
Jul 6 2023 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2023.1174113 | Association between dietary antioxidant quality score and severity of coronavirus infection: a case–control study |
| 88% lower severe cases (p<0.0001). Case control study of 295 COVID-19 patients in Iran, showing lower risk of severe cases with higher dietary antioxidant quality scores, and with higher intake of vitamin D. | ||
Jun 7 2023 |
et al., Journal of Pediatric Nursing, doi:10.1016/j.pedn.2023.06.003 | COVID-19 effects on diet, sleep, and physical activity among mid- to late-adolescents residing in the deep south in the United States |
| Prospective study tracking sleep, diet, and physical activity for adolescents in the USA before and during the COVID-19 pandemic, showing negative health effects of the pandemic / restrictions. | ||
Apr 13 2023 |
et al., Indian Journal of Medical Research, doi:10.4103/ijmr.ijmr_1701_22 | Indian food habit & food ingredients may have a role in lowering the severity & high death rate from COVID-19 in Indians |
| Nutrigenomics study of blood transcriptomes from Indian and western COVID-19 patients, showing Indian dietary habits and food ingredients including higher zinc, iron, curcumin, fiber, catechins, and EGCG may be associated with reduced sev.. | ||
Apr 12 2023 |
et al., Scandinavian Journal of Public Health, doi:10.1177/14034948231163960 | Poor health status before the COVID-19 pandemic is associated with unfavourable changes in health-related lifestyle |
| Analysis of 3,834 adults in Finland, showing that people with poor health status were more likely to have unfavorable lifestyle changes during the pandemic, including decreased vegetable consumption, decreased leisure-time physical activi.. | ||
Mar 31 2023 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2023.1075061 | The association between inflammatory and immune system biomarkers and the dietary inflammatory index in patients with COVID-19 |
| 99% lower ICU admission (p<0.0001). Retrospective 500 COVID-19 patients, showing dietary inflammatory index (DII) and energy-adjusted dietary inflammatory index (E-DII) associated with COVID-19 severity. | ||
Mar 3 2023 |
et al., Clinical Nutrition Open Science, doi:10.1016/j.nutos.2023.02.001 | The association of dietary approach to stop hypertension (DASH) diet with hospitalization risk in patients with COVID-19 |
| 81% lower hospitalization (p=0.002). Case control study with 53 inpatients and 88 outpatients in Iran, showing lower risk of hospitalization with increased adherence to the DASH (Dietary Approach to Stop Hypertension) diet. Increased intake of fruits, vegetables and low-fat .. | ||
Feb 18 2023 |
et al., International Journal of Preventive Medicine, doi:10.4103/ijpvm.ijpvm_129_21 | The Association between Dietary Inflammatory Index with Risk of Coronavirus Infection and Severity: A Case-Control Study |
| Case control study in Iran with 100 COVID-19 cases and 100 healthy controls, showing no significant association between DII score and cases or symptoms. Results are only provided for DII as a continuous variable. COVID‐19 patients had a h.. | ||
Feb 6 2023 |
et al., JAMA Internal Medicine, doi:10.1001/jamainternmed.2022.6555 | Adherence to Healthy Lifestyle Prior to Infection and Risk of Post–COVID-19 Condition |
| 9% lower PASC (p=0.43). Prospective analysis of 32,249 women from the Nurses’ Health Study II in the USA, showing lower risk of PASC with a healthy lifestyle, and in a dose-dependent manner. Participants with 5 or 6 healthy lifestyle factors had significantly lo.. | ||
Jan 26 2023 |
et al., Medicina, doi:10.3390/medicina59020227 | Adherence to the Mediterranean Diet Association with Serum Inflammatory Factors Stress Oxidative and Appetite in COVID-19 Patients |
| 25% lower progression (p<0.0001). Retrospective 600 COVID-19 patients in Iran with moderate/severe CT scans, showing lower prevalence of dyspnea, fever, taste/smell abnormalities, and cough with high adherence to the Mediterranean diet in unadjusted results. | ||
Dec 28 2022 |
et al., Annals of Agricultural and Environmental Medicine, doi:10.26444/aaem/156939 | Diet and selected elements of lifestyle in the Polish population before and during the COVID-19 pandemic – a population study |
| Retrospective 964 people in Poland showing unfavourable changes in diet during the COVID-19 pandemic, with increased intake of total lipids, saturated fatty acids, and sucrose. | ||
Dec 14 2022 |
et al., SSRN Electronic Journal, doi:10.2139/ssrn.4300209 | Associations between the Dietary Inflammatory Index and COVID-19 Outcomes in the UK Biobank Cohort |
| 24% lower mortality (p=0.13), 28% lower severe cases (p=0.0003), and 15% fewer cases (p<0.0001). UK Biobank retrospective 196,154 participants with 11,288 COVID-19 cases, showing lower COVID-19 mortality, severity, and incidence for lower dietary inflammatory scores. | ||
Nov 11 2022 |
et al., Journal of Medical Virology, doi:10.1002/jmv.28298 | The effect of adherence to high-quality dietary pattern on COVID-19 outcomes: A systematic review and meta-analysis |
| 62% lower hospitalization (p=0.004) and 28% fewer cases (p<0.0001). Meta analysis of 5 diet and COVID-19 studies, showing lower risk of COVID-19 cases and hospitalization with higher quality diets. | ||
Oct 25 2022 |
et al., European Journal of Public Health, doi:10.1093/eurpub/ckac130.235 | Dietary factors and risk of SARS-CoV-2 infection in the Moli-sani Study Cohort |
| Retrospective 1,096 participants showing high consumption of vegetables or fruits and nuts associated with lower risk of COVID-19 cases. | ||
Oct 24 2022 |
et al., American Journal of Lifestyle Medicine, doi:10.1177/15598276221135541 | The Association between Lifestyle Risk Factors and COVID-19 Hospitalization in a Healthcare Institution |
| 75% lower hospitalization (p=0.0003). Retrospective 546 COVID+ patients in the USA, showing lower risk of hospitalization with higher consumption of vegetables. | ||
Oct 6 2022 |
et al., BMJ Military Health, doi:10.1136/military-2022-002173 | Adherence to Healthy Eating Index-2015 and severity of disease in hospitalised military patients with COVID-19: a cross sectional study |
| Retrospective 295 hospitalized COVID-19 patients in Iran, showing significantly lower HEI-2015 diet scores for patients admitted to the ICU. Adjusted results are only provided for HEI-2015 score as a continuous variable. | ||
Sep 29 2022 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2022.934568 | Association of fruits, vegetables, and fiber intake with COVID-19 severity and symptoms in hospitalized patients: A cross-sectional study |
| 67% lower severe cases (p=0.003). Retrospective 250 hospitalized patients in Iran, showing higher consumption of fruits, vegetables, and fiber associated with lower COVID-19 severity. | ||
Sep 6 2022 |
et al., Nutrition and Health, doi:10.1177/02601060221124068 | Association of food habit with the COVID-19 severity and hospitalization: A cross-sectional study among the recovered individuals in Bangladesh |
| Retrospective 1,025 COVID-19 patients in Bangladesh finding reduced risk of COVID-19 severity and hospitalization with high consumption of fruit, vegetables, and fish; moderate consumption of garlic, onion, and turmeric; and tea and honey. | ||
Aug 19 2022 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2022.929384 | Major dietary patterns in relation to disease severity, symptoms, and inflammatory markers in patients recovered from COVID-19 |
| 69% lower severe cases (p=0.004), 56% lower hospitalization (p=0.07), and 68% improved recovery (p=0.003). Retrospective 250 recovered COVID-19 patients, showing lower risk of severe cases and shorter recovery and hospitalization times with a healthy diet. Notably, all individual symptoms show lower incidence with a healthy diet with the excep.. | ||
Aug 16 2022 |
et al., European Journal of Nutrition, doi:10.1007/s00394-022-02982-0 | Impact of ultra-processed food intake on the risk of COVID-19: a prospective cohort study |
| 16% fewer cases (p<0.0001). Prospective study of 41,012 UK Biobank participants, showing higher risk of COVID-19 cases with ultra-processed food consumption. | ||
Aug 9 2022 |
et al., The American Journal of Clinical Nutrition, doi:10.1093/ajcn/nqac219 | Long-term diet and risk of SARS -CoV-2 infection and Coronavirus Disease 2019 (COVID-19) severity |
| 19% fewer cases (p=0.008). Analysis of 42,935 participants showing lower risk of COVID-19 with healthier diets. Risk of severe cases was also lower with healthier diets, while not reaching statistical significance. Severity results are only provided with diet indic.. | ||
Jul 19 2022 |
et al., Frontiers in Medicine, doi:10.3389/fmed.2022.911273 | Higher Adherence to the Mediterranean Dietary Pattern Is Inversely Associated With Severity of COVID-19 and Related Symptoms: A Cross-Sectional Study |
| 77% lower severe cases (p=0.0002). Retrospective 250 COVID-19 patients in Iran, showing lower risk of severe disease with greater adherence to a Mediterranean diet. | ||
May 27 2022 |
et al., Nutrients, doi:10.3390/nu14112254 | Suboptimal Consumption of Relevant Immune System Micronutrients Is Associated with a Worse Impact of COVID-19 in Spanish Populations |
| Ecological study in Spain, showing diets lower in vitamin D, A, B9, and zinc in regions with the highest COVID-19 incidence and mortality. Vitamin D intake was associated with lower prevalence, incidence, and a combined incidence+mortalit.. | ||
May 18 2022 |
et al., Nutrients, doi:10.3390/nu14102105 | Nutritional Risk Assessment Scores Effectively Predict Mortality in Critically Ill Patients with Severe COVID-19 |
| Retrospective 90 severe COVID-19 ARDS patients in Romania, showing nutritional risk assessment scores PNI, CONUT, NUTRIC, and mNUTRIC to be independent predictors of mortality. | ||
May 11 2022 |
et al., European Journal of Preventive Cardiology, doi:10.1093/eurjpc/zwac056.304 | Cardiovascular risk factor insights into the Tesco 1.0 Dataset |
| Tesco grocery purchase retrospective, showing COVID-19 mortality correlated with myocardial infarction mortality risk factors. Salt, percentage of fat and oils, and total weight increased risk, while fiber was protective. | ||
May 2 2022 |
et al., American Journal of Lifestyle Medicine, doi:10.1177/15598276221097621 | The Role of Nutrition in COVID-19: Taking a Lesson from the 1918 H1N1 Pandemic |
| Review of evidence suggesting that a healthy diet reduces risk for COVID-19. | ||
Apr 29 2022 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2022.837458 | COVID-19 Illness Severity in the Elderly in Relation to Vegetarian and Non-vegetarian Diets: A Single-Center Experience |
| 72% lower severe cases (p=0.23) and 11% fewer moderate/severe cases (p=0.66). Retrospective 509 COVID-19 patients in Taiwan, showing higher risk of critical COVID-19 cases with non-vegetarian diets. | ||
Mar 29 2022 |
et al., International Journal of Clinical Practice, doi:10.1155/2022/5452488 | The Association between Energy-Adjusted Dietary Inflammatory Index, Body Composition, and Anthropometric Indices in COVID-19-Infected Patients: A Case-Control Study in Shiraz, Iran |
| 65% fewer cases (p<0.0001). Retrospective 133 COVID-19 patients and 322 controls, showing higher risk of COVID-19 for diets that have a higher inflammatory index (E-DII). | ||
Jan 29 2022 |
et al., Mediterranean Journal of Nutrition and Metabolism, doi:10.3233/MNM-211521 | The difference in the dietary inflammatory index, functional food, and antioxidants intake between COVID -19 patients and healthy persons |
| Retrospective dietary survey analysis of 500 COVID-19 patients and 500 healthy matched controls in Iran, showing dietary inflammatory index associated with increased risk of COVID-19. IR.ARUMS.REC.1400.008. | ||
Jan 24 2022 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2021.805533 | Components of the Mediterranean Diet and Risk of COVID-19 |
| 78% lower severe cases (p=0.15), 15% fewer symptomatic cases (p=0.31), and 20% fewer cases (p=0.14). Retrospective 5,194 participants in Spain with 382 COVID-19 cases, showing lower risk of COVID-19 with high adherence to a Mediterranean diet, with statistical significance only when excluding healthcare professionals. | ||
Jan 14 2022 |
et al., Nutrients, doi:10.3390/nu14020350 | Associations of Nutritional Behavior and Gut Microbiota with the Risk of COVID-19 in Healthy Young Adults in Poland |
| 82% fewer cases (p=0.005). Retrospective 95 people in Poland, showing significantly lower risk of COVID-19 with higher consumption of fruits, vegetables, and nuts. Diets with higher consumption of fruits, vegetables, and nuts had a significantly lower dietary infla.. | ||
Dec 30 2021 |
et al., Scientific Reports, doi:10.1038/s41598-021-04350-0 | Flight attendant occupational nutrition and lifestyle factors associated with COVID-19 incidence |
| 66% fewer cases (p=0.009). Retrospective 84 flight attendants, 52 reporting COVID-19 status and diet quality, showing higher risk of COVID-19 with lower self-reported diet quality. | ||
Dec 31 2021 |
et al., Clinical Nutrition ESPEN, doi:10.1016/j.clnesp.2021.09.606 | Influence of mediterranean diet on survival from covid-19 disease |
| 53% lower mortality (p=0.05). Retrospective 89 COVID-19 patients in Spain, showing lower mortality with adherence to the Mediterranean diet. | ||
Nov 30 2021 |
et al., BMC Medicine, doi:10.1186/s12916-021-02168-1 | Nutritional risk factors for SARS-CoV-2 infection: a prospective study within the NutriNet-Santé cohort |
| Analysis of 7,766 adults in France, showing higher intakes of vitamin C, folate, vitamin K, dietary fibre, and fruit and vegetables associated with lower seropositivity. | ||
Sep 18 2021 |
et al., Nutrients, doi:10.3390/nu13093258 | Single and Combinative Impacts of Healthy Eating Behavior and Physical Activity on COVID-19-like Symptoms among Outpatients: A Multi-Hospital and Health Center Survey |
| 15% fewer symptomatic cases (p=0.006). Analysis of 3,947 participants in Vietnam, showing significantly lower risk of COVID-19-like symptoms with physical activity and with a healthy diet. The combination of being physically active and eating healthy reduced risk further compa.. | ||
Aug 31 2021 |
et al., Brain, Behavior, and Immunity, doi:10.1016/j.bbi.2021.04.022 | Lifestyle risk factors and infectious disease mortality, including COVID-19, among middle aged and older adults: Evidence from a community-based cohort study in the United Kingdom |
| 3% higher mortality (p=0.85). Retrospective 468,569 adults in the UK, showing significantly lower COVID-19 mortality with physical activity. | ||
Aug 23 2021 |
et al., British Journal of Nutrition, doi:10.1017/S0007114521003214 | The relationship between Dietary Inflammatory Index and disease severity and inflammatory status: a case–control study of COVID-19 patients |
| 92% fewer cases (p<0.0001). Retrospective 60 COVID-19 hospitalized patients and 60 controls in Iran, showing pro-inflammatory diets associated with COVID-19 cases and severity. IR.KUMS.REC.1399·444, IR.TBZMED.REC.1399·225. | ||
Jul 30 2021 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2021.707359 | Inverse Association Between the Mediterranean Diet and COVID-19 Risk in Lebanon: A Case-Control Study |
| Retrospective 399 people in Lebanon, showing a significant inverse association between the MedDiet score, corresponding to the level of adherence to the Mediterranean diet, and the risk of COVID-19. | ||
Jul 9 2021 |
et al., Food Science & Nutrition, doi:10.1002/fsn3.2458 | Nutritional and lifestyle changes required for minimizing the recovery period in home quarantined COVID-19 patients of Punjab, Pakistan |
| Survey of 80 recovered COVID-19 patients in Pakistan, showing faster recovery with improved nutrition. | ||
Jun 25 2021 |
et al., Gut, doi:10.1136/gutjnl-2021-325353 (date from preprint) | Diet quality and risk and severity of COVID-19: a prospective cohort study |
| 41% lower severe cases (p<0.0001) and 18% fewer cases (p<0.0001). Retrospective 592,571 participants in the UK and USA with 31,815 COVID-19 cases, showing lower risk or COVID-19 cases and severity for higher healthful plant-based diet scores. Notably, the assocation was less evident with higher levels o.. | ||
Jun 7 2021 |
et al., BMJ Nutrition, Prevention & Health, doi:10.1136/bmjnph-2021-000272 | Plant-based diets, pescatarian diets and COVID-19 severity: a population-based case–control study in six countries |
| 72% fewer moderate/severe cases (p=0.02) and 19% fewer cases (p=0.24). Retrospective healthcare workers in six countries with exposure to COVID-19 patients, showing lower risk of moderate/severe COVID-19 with plant-based diets. | ||
May 19 2021 |
et al., Nutrients, doi:10.3390/nu13051721 | Mediterranean Diet and SARS-COV-2 Infection: Is There Any Association? A Proof-of-Concept Study |
| Retrospective 1,206 healthcare professionals in Italy, showing the risk of COVID-19 infection inversely associated with adherence to the Mediterranean diet. | ||
Apr 20 2021 |
et al., eLife, doi:10.7554/eLife.66537 | Insights from a Pan India Sero-Epidemiological survey (Phenome-India Cohort) for SARS-CoV2 |
| 40% lower seropositivity (p<0.0001). Retrospective 10,427 volunteers in India, 1,058 anti-nucleocapsid antibody positive, showing lower risk of seropositivity with a vegetarian diet. | ||
Mar 5 2021 |
et al., Frontiers in Nutrition, doi:10.3389/fnut.2021.591964 | Negative Association Between Mediterranean Diet Adherence and COVID-19 Cases and Related Deaths in Spain and 23 OECD Countries: An Ecological Study |
| Analysis of 17 regions in Spain, showing an inverse association between adherence to the Mediterranean diet and COVID-19 cases and mortality. | ||
Feb 15 2021 |
et al., American Journal of Blood Research, 11:1 | Seroprevalence of IgG against SARS-CoV-2 and its determinants among healthcare workers of a COVID-19 dedicated hospital of India |
| 20% lower IgG positivity (p=0.32). Retrospective 689 healthcare workers in India, showing non-statistically significant lower risk of IgG positivity with a vegetarian diet in unadjusted results. | ||
Sep 8 2020 |
et al., Nutrients, doi:10.3390/nu12092738 | Current State of Evidence: Influence of Nutritional and Nutrigenetic Factors on Immunity in the COVID-19 Pandemic Framework |
| Ecological study of European countries analyzing 10 vitamins and minerals endorsed by the European Food Safety Authority as having sufficient evidence for a causal relationship between intake and optimal immune system function: vitamins D.. | ||
Please send us corrections, updates, or comments.
c19early involves the extraction of 100,000+ datapoints from
thousands of papers. Community updates
help ensure high accuracy.
Treatments and other interventions are complementary.
All practical, effective, and safe
means should be used based on risk/benefit analysis.
No treatment or intervention is 100% available and effective for all current
and future variants.
We do not provide medical advice. Before taking any medication,
consult a qualified physician who can provide personalized advice and details
of risks and benefits based on your medical history and situation. FLCCC and WCH
provide treatment protocols.
Thanks for your feedback! Please search before submitting papers and note
that studies are listed under the date they were first available, which may be
the date of an earlier preprint.