Dietary strategies aimed at supporting immunity to fight COVID-19 are continually being considered. Unfortunately, as in the case of drugs, studies in humans have not confirmed any specific food components to be effective in the case of COVID-19. We know that the immune system is the key to reducing the severity of COVID-19, and perhaps by providing food that supports the immune system we can support preventive measures.
Numerous clinical studies have shown that nutraceuticals can beneficially stimulate the immune response in patients with various diseases, such as cancer or AIDS, and in healthy people at risk of viral infections. Natural compounds are commonly recognized as valuable agents in the fight against viruses due to their structural diversity and safety.
Many products consumed by people and used in traditional medicine have been shown to contain substances with anti-inflammatory, antibacterial, and antiviral properties, e.g., vitamin C in the fruit or juice of raspberries or elderberries, hesperidin in St. John’s wort, kaempferol and methylglyoxal in honey, allicin in garlic and onion, gingerols in ginger, curcumin in turmeric, and piperine in black pepper.
Following are a few food sources that have been shown to support the Immune System:
Elderberry
The elderberry (Sambucus nigra) may be useful against COVID-19 due to its capacity to stimulate the immune system and inhibit the replication of viruses. It could be especially helpful during the initial stage of coronavirus infection or for preventing infection. By inhibiting replication of the virus, elderberries significantly increase the production of pro-inflammatory cytokines. A review by the Natural Standard Research Collaboration concluded that there is evidence in support of the use of elderberries to treat the flu, which may or may not be of significance for the prevention of COVID-19. The typical dose of 2:1 elderberry extract is 10–60 mL a day for adults and 5–30 mL a day for children.
Selenium
Selenium plays an important role in protecting the respiratory system, especially against viral infections. Deficiencies of selenium in the diet can affect the immune response. Using selenium in combination with CoQ10 decreases the non-specific inflammatory response from cardiovascular causes.
The role of selenium in normal immune system function is linked to its antioxidant properties. In addition, the beneficial effect of appropriate selenium doses on the immune system is important in patients infected with SARS-Cov-2. Selenium administration is recommended at doses from 100 to 200 mcg a day.
Vitamin D
Vitamin D is a significant factor in protection against infectious respiratory diseases and plays an important role in the prevention of COVID-19. Research has shown the infection rate to be higher in countries with higher latitudes and/or lower levels of vitamin D. In another study, from Los Angeles, vitamin D deficiency was identified as a risk factor for positive COVID-19 tests.
Severe vitamin D deficiency is often observed in patients in critical condition and seems to be linked to a poor prognosis. It is associated with exacerbation of pneumonia, leading to acute respiratory distress syndrome. For prevention, long-term intake of vitamin D at dosages of ≤ 5000 mg D3/day is recommended. Vitamin D stimulates and modulates the immune response and protects the upper and lower respiratory tract from viral infection.
Vitamin C
Vitamin C takes part in physiological processes associated with immunity and in the blood clotting process, which is of importance in the course of COVID-19. In order for the body to defend itself against viruses, it must have an adequate level of vitamin C. Clinical trials have shown that vitamin C reduces the frequency, duration, and severity of the common cold and the incidence of pneumonia. Typical daily doses of vitamin C range from 500 to 3000 mg, and even higher doses are used in periods of acute infection.
Many studies have confirmed the beneficial effects of high doses of vitamin C to treat lung damage, alleviate severe sepsis, and reduce the durations of stays in intensive care units.
These are just a few of the less popular supplements you need to take to support your immune system. The primary source for getting these vitamins is your diet. According to well-known recommendations, half of one’s daily diet should consist of vegetables and fruit. We should consume at least five portions of fruit and vegetables every day, predominantly vegetables (3–4 portions of vegetables and 1–2 portions of fruit). Ideally, they should be of different colors and raw or minimally processed.
A healthy, well-balanced diet has a beneficial effect on most chronic health conditions. A diet with high antioxidant and anti-inflammatory potential may mitigate the severity of many health issues.
