Nutrition and COVID-19

The goal of this article is to provide readers with this reviewer’s perspective on the coronavirus disease 2019 (COVID-19) with a focus on what role diet and nutrition may play in its prevention and treatment.COVID-19 is caused by a coronavirus similar with the one that caused severe acute respiratory syndrome (SARS) back in 2003.  According to the World Health Organization (WHO), a total of 8,098 people worldwide became sick with SARS during the 2003 outbreak. Of these, 774 died (1). This first SARS coronavirus is now referred to as SARS-CoV-1. Both SARS coronaviruses appear to have originated in bats found in China.  Fortunately, this SARS-CoV-1 had almost no impact in the US, perhaps because it was far less contagious this new species of coronavirus (SARS-CoV-2) that causes COVID-19. We know SARS-CoV-2 has already infected millions of Americans and as of mid-July more than 170,000 Americans have died with COVID-19. The number of new cases being diagnosed in the US is again surging with 60,000 new cases diagnosed in a single day in July. Dr. Anthony Fauci recently predicted we could see 100,000 new cases of SARS-CoV-2 being diagnosed daily (2).It is beyond the scope of this review to discuss the medical implications of this SARS-CoV-2 pandemic, but for those interested in the pathophysiology, transmission, diagnosis, and medical treatment of COVID-19 patients here is a good recent review. The most salient part of this recent JAMA review article from a nutrition perspective is this statement about comorbidities that are most likely to increase the risk of more serious COVID-19 disease symptoms and increase the risk of dying from a SARS-CoV-2 infection:

“The most common comorbidities in hospitalized patients include hypertension (present in 48%-57% of patients), diabetes (17%-34%), cardiovascular disease (21%-28%), chronic pulmonary disease (4%-10%), chronic kidney disease (3%-13%), malignancy (6%-8%), and chronic liver disease (<5%)” (3).

How Diet May Reduce the Risk of Death from CoVID-19Dr. Fauci's Congressional testimony emphasized that people with these diet and lifestyle-caused illnesses (including being overweight and having hypertension, diabetes, and failing kidneys) greatly increases one’s risk of being hospitalized and dying if infected with SARS-CoV-2 (4). A calorie-dense diet low in fiber and with a lot of beverage calories promotes increased inflammation, insulin resistance, weight gain, and the development of type 2 diabetes (5).A diet high in salt promotes hypertension, especially in overweight people with insulin resistance. Indeed, hypertension develops in more than 90% of Americans by the time they are in their 70s or 80s. A typical modern Western diet and central adiposity is now the #1 cause of fatty liver disease that is also associated with more serious disease in patients with COVID-19. And diabetes and hypertension are the two greatest risk factors leading to renal failure (6).Asthma is also promoted by obesity and a diet high in salt. People with asthma are also at a heightened risk of dying from COVID-19 (7). People with cancer are also at elevated risk of dying with COVID-19. Research suggests that up to 70% of all cancer deaths are associated with a typical modern Western-style diet (8).Most of the deaths caused by a SARS-CoV-2 infection result in markedly increased levels of inflammation and thrombosis (or from blood clots). Weight gain and diets higher in saturated fat have long been known to increase the levels of inflammatory substances in the blood. Elevated inflammatory markers (eg, C-reactive protein, ferritin, tumor necrosis factor-?, IL-1, IL-6) appear to promote the severe acute inflammatory response in the lungs is described as a “cytokine storm” may be more likely in obese people consuming a typical saturated-fat-rich American diet. It has long been known that diets higher in fat elevate clotting factor VII, which promotes blood clot formation. Diets high in saturated fat and low in omega-3 fatty acids elevate blood thromboxane levels that also leads to more blood clots (9).Can Food Supplements Prevent or Treat COVID-19?Nutrition quackery thrives on fear and there is plenty of that regarding COVID-19. Not surprisingly, the list of companies promoting various dietary and herbal remedies for people worried about COVID-19 is growing rapidly. Here is a list of companies making dubious claims that their food supplements and herbal products can boost immunity and help prevent and/or treat COVID-19 (10). There are no controlled clinical trials showing zinc, vitamin D, fish oils, or intravenous vitamin C are of any benefit for preventing or treating COVID-19.Bottom Line: It seems likely that one reason many Americans are at elevated risk form catching SARS-CoV-2 and experiencing more serious disease or dying from COVID-19 is because of the typical modern diet and lifestyle. Adopting a healthier diet lower in saturated fat, salt, and cholesterol and higher in whole fruits, vegetables, and whole grains will not prevent people from catching this new coronavirus. However, people who follow a healthy diet and lifestyle will prevent and even reverse many the co-morbid illnesses that markedly increase the risk of more serious outcomes should they catch this all-too-common new coronavirus. Prevention, at least until there is an effective vaccine, will require social distancing and wearing a mask -- especially in crowded indoor environments for older people with serious co-morbid illness. Those who work with and/or have older relatives at high risk from catching SARS-CoV-2 will want to avoid interacting with high-risk individuals, especially if they have a fever, dry cough, shortness of breath and/or have reason to believe they may have a SARS-CoV-2 infection.By James J. Kenney, PhD, FACN  References:

1. https://www.cdc.gov/sars/about/fs-sars.html
2. https://www.statnews.com/2020/06/30/u-s-could-see-100000-new-covid-19-cases-per-day-fauci-says/
3. https://jamanetwork.com/journals/jama/fullarticle/2768391?guestAccessKey=1700a28b-b0a0-41a9-8e55-5c66b5f4971b&utm_source=For_The_Media&utm_medium=referral&utm_campaign=ftm_links&utm_content=tfl&utm_term=071020
4. https://www.youtube.com/watch?v=Qyjv7vLCc80&feature=youtu.be
5. https://www.sciencedirect.com/science/article/pii/S2212877815001830
6. https://www.joslin.org/patient-care/diabetes-education/diabetes-learning-center/diabetes-high-blood-pressure-and-kidney
7. https://academic.oup.com/nutritionreviews/article/doi/10.1093/nutrit/nuaa005/5804968
8. https://clinmedjournals.org/articles/jnmdc/journal-of-nutritional-medicine-and-diet-care-jnmdc-4-029.php?jid=jnmdc
9. https://books.google.com/books?id=Wa8RAAAAQBAJ&pg=PA607&lpg=PA607&dq=Saturated+fat+increases+thromboxane+and+other+blood+clotting+risk+factors&source=bl&ots=RSImv4rwo4&sig=ACfU3U29Fczr6REB2_sMCGB0AV4ynaCSwQ&hl=en&sa=X&ved=2ahUKEwjZnLHRwcXqAhUMCawKHZtHCe8Q6AEwBHoECAkQAQ#v=onepage&q=Saturated%20fat%20increases%20thromboxane%20and%20other%20blood%20clotting%20risk%20factors&f=false
10. Dubious COVID-19 Treatments and Preventives | Center for Inquiry.