Nutrition versus coronavirus
At its heart, eating against coronavirus is simply eating to support your immune system. This post is based on a 35-page review of emerging research titled Evidence Supporting a Phased Immuno-physiological Approach to COVID-19 From Prevention Through Recovery. The paper explains evidence-based tactics towards [1] individuals infected with SARS-CoV-2 (the virus that causes COVID-19), and [2] those of us trying to avoid becoming a vector for the virus. This post focuses on the latter (prevention), since treatment is beyond the scope of a blog post. If you are already sick from the virus, consult an appropriate healthcare professional.
Standard disclaimer: this post is not a substitute for nutrition advice from a registered dietitian who can formulate a plan based on your own lifecycle stage, gender, genetic makeup, and disease history.
Let food be thy medicine and medicine be thy food.”
― Hippocrates
Let food be thy medicine and medicine be thy food—until a vaccine is found, and then you should get vaccinated.”
― Expat in Montreal
Nutrient density for immune support
Specifically, we’d like to promote efficient activation of the innate, or “non-specific”, immune system, which can become compromised by SARS-CoV-2.
A nutrient dense diet accentuating unrefined, plant-based foods is the foundation for good health in normal times. Such a habit is especially useful in working towards a state in the body where [1] the body is not deficient in nutrients necessary for an adequate and rapid immune system response, and [2] inflammation is reasonably low before the onset of a serious challenge to the immune system. In a healthy individual these are important, but for one dealing with conditions such as hypertension, cardiovascular disease, diabetes, or asthma, this type of eating could be the difference between life and death when confronted with COVID-19.
A beautiful papaya salad with skewered fresh tempeh [left]. Get it at the Malaysian / Singaporean restaurant Satay Brothers in Montreal’s Saint-Henri. A variety of vegetables from the farmer’s market [right]. Abundant nutrients are needed in eating against coronavirus.
Eating against coronavirus: Macronutrients
In terms of macronutrients, putting thought into your carbohydrate sources is a good place to start. Reviewing your knowledge of the glycemic index (GI) helps, but as put by Harvard Medical School, glycemic load (GL) “gives you a more accurate picture of a food’s real-life impact on your blood sugar”. If you want to go nuts with GI & GL, download this table for data on over 750 different types of foods. In eating against coronavirus, choosing foods with a lower glycemic load is preferred.
Cutting down on foods rich in refined carbs can often automatically help you eat fewer poor quality fats. Yet beyond simply detouring away from less desirable food choices, we also would do well to actively seek out high-quality fats not present in most foods, like those found in mackerel, salmon, lake trout, sardines, and herring. Beyond consuming whole foods, fish oil is the most generous source of the crucial fatty acids EPA & DHA. These two fatty acids result in metabolic products called specialized pro-resolving lipid mediators (SPMs) that might be useful against the onset of a virus like SARS-CoV-2.
The fiber provided by minimally refined plant foods (vegetables, fruits, whole grains) not only helps keep baseline inflammation low, it also promotes immune function at the level of gut and lung mucosal membranes. Minimally processed plant foods are also rich in polyphenols and other antioxidants that will decrease oxidative stress. For some, increasing intake of whole grains will mean setting aside their mental conditioning with scientifically flimsy propaganda such as “grains cause inflammation”.
Eating against coronavirus: Micronutrients
As for micronutrients, only a handful require greater attention than usual.
Vitamin D
While vitamin D is found in some foods, sunlight is the source of the vitamin people tend to know about. What most people don’t know is that relying on sunlight for the vitamin can lead to a false sense of security. Vitamin D insufficiency is not uncommon in North America, especially above the southernmost states.
Vitamin A
A minority of North Americans may not have adequate vitamin A intake. Obtaining dietary vitamin A from carotenoid-containing vegetables is standard nutritional advice, but it should be mentioned that not every individual is able to efficiently convert provitamin A carotenoids (like beta-carotene) into the form of the vitamin needed by the body. Thus, alternative sources of the vitamin include dairy foods, fish, fortified cereals, and dietary supplements.
Zinc
If you don’t consume much red meat or poultry (for example, if you are vegetarian), then it helps to eat the following when trying to meet your zinc requirement: nuts, seeds, legumes, whole grains, dairy, dark chocolate (80–100% cocoa), and some shellfish (crab and especially oysters).
Bioactive compounds
If you like garlic, try mincing some raw garlic and sprinkling it on a meal (one that is compatible with garlic, obviously). Careful, it’s strong stuff to the mouth and stomach—but also powerful against viruses in the laboratory. This is at least in part due to garlic’s glutathione (GSH) content, a sulfur-containing compound. Cruciferous vegetables (most popularly: broccoli, brussels sprouts, cabbage, cauliflower, and kale) are a fine source for sulfur / GSH. Eating curries also favors glutathione intake due to ingredients like turmeric and cardamom. Turmeric, for example, supplies curcumin, which serves both antioxidant and antiinflammatory purposes inside the body.
While rich animal food sources of cysteine are poultry, eggs, and beef, dietary cysteine can also be obtained from whole grains. If doubting your cysteine intake, taking supplemental N-Acetyl Cysteine (NAC) provides cysteine that can easily become part of GSH in your body.