A review has taken up the importance of diet, with a focus on micronutrients, in the prevention and reduction of complications due to Covid-19 in the population and with a special emphasis on elderly individuals. An excursus was devoted to vitamins and minerals and recommended intake doses. (1)
Nutritional problems for the elderly
Many micronutrients help support the integrity of physical barriers (e.g., intestinal), immune cell development and motility, and produce useful substances to stimulate immunomodulation and useful inflammatory processes and to attenuate their intensity and harmful effects. If they are deficient, the innate and adaptive immune system and resistance to infection can be severely compromised. (2)
Older people are subject to a natural reduction in natural defenses due to older age and marked malnutrition, especially of micronutrients, contributing to increased exposure to various diseases. Increased drug intake may lead to reduced appetite or nutrient utilization, exacerbating this phenomenon.
Lack of information
The importance of micronutrients is well documented for the proper functioning of the innate and adaptive immune system, with special emphasis on vitamins and minerals. A major shortcoming in the prevention of Covid-19 has been blamed on the marginal role of the media and medical institutions in the continued promotion of these elements in the fight against the virus.
Since the beginning of the pandemic, however, great emphasis has been placed on the importance of diet in boosting the immune system, such as in the case of marine Omega-3s (normally poorly consumed by the population) and their ability to stimulate immunomodulation and reduce upper respiratory tract disease, of which Covid-19 is a part. (3)
Vitamins and Covid-19
Vitamin D was the one immediately given the most consideration and considered most effective in preventing from Covid and other numerous infectious diseases. In an Italian study, a positive correlation between deficiency of the vitamin and the incidence of the disease had been identified early on, but at the health care level little account was taken of it and its possible benefit was even denied, as it turned out.
Vitamin A is also known as the ‘anti-infective vitamin’ due to its importance in the proper functioning of the immune system and prevention against diseases due to bacteria and protozoa, as well as viruses. The action against Covid-19 is imputed to the ability to reduce inflammatory processes and antioxidant properties, in synergy with immunomodulatory action.
Vitamin C is perhaps best known when it comes to reducing flu symptoms, especially during the winter period. In Covid, it plays an important role in modulating the cytokine storm, believed to be the main culprit of severe complications due to the virus, and promotes the mobilization of immune cells at the sites of infection. In Shanghai, it was even included in the official guidelines in the fight against coronovirus.
Minerals and Covid-19
Selenium helps protect cells from oxidative stress and excessive inflammatory responses. A prolonged deficiency of it can make even a normal flu dangerous, and its proper supplementation has been shown to have an effective protective effect.
Zinc plays a key role in immune system function, among other micronutrients, and has specific antiviral action that can inhibit their replication. It is able to enhance the action of other micronutrients, such as vitamin A, and in turn exerts antioxidant and anti-inflammatory actions that are useful in reducing Covid risk and severity due to infection.
Recommendations
For the purpose of prevention or support in hospital treatment, recommendations are given on the doses of vitamins and minerals to be taken for the general population to ensure a greater likelihood of reducing the risk of infection or resulting complications. Specifically:
Vitamins A and D: 2,000 to 4,000 I.U. daily for prevention purposes. A concentrated dose between 50,000 to 200,000 I.U. and a daily intake of 5,000 to 10,000 I.U. even after leaving the hospital are strongly recommended.
Vitamin C: 1,000 to 3,000 mg in several daily doses, preferably together with quercetin as prevention. This is increased to 15-30 g daily until the first 10 days and followed with a halved dose weekly to reduce complications.
Selenium: 100 to 200 micrograms of selenium daily for prevention. 1 mg daily in the first week and half dose thereafter for protective purposes.
Zinc: 10 to 20 mg of zinc daily for prevention. 100 to 150 mg daily in the first week or 20-50 mg + 7.5 g vitamin C to start and then 20-50 mg daily to end the recovery phase.
Conclusions
Micronutrient supplementation is a safe, effective, and low-cost strategy to boost the immune system and counteract infection and any adverse effects due to Sars-CoV-2. Therefore, the identification of nutritional status in the population, especially the elderly, should be a common practice to be considered in this emergency situation.
Vitamins and minerals are very important in fighting Covid, but they are not the only ones to consider. Other numerous macro- and micronutrients should be a regular part of everyone’s diet, and its composition also influences immune development and protection against the virus. (4)
Dario Dongo and Andrea Adelmo Della Penna
Notes
(1) Gröber et al. (2021) The coronavirus disease (COVID-19) – A supportive approach with selected micronutrients. Int. J. Vitam. Nutr. Res. 0:1-22, https://doi.org/10.1024/0300-9831/a000693
See also Dario Dongo and Andrea Adelmo Della Penna. Over-55, strengthen the immune system with vitamin and mineral supplements. Study. GIFT (Great Italian Food Trade) 23.8.20 https://www.greatitalianfoodtrade.it/salute/over-55-rafforzare-il-sistema-immunitario-con-integratori-di-vitamine-e-minerali-studio
(2) Karadima et al. (2016) Drug-micronutrient interactions: food for thought and thought for action. The EPMA Journal 7:10, https://doi.org/10.1186/s13167-016-0059-1
(3) Dario Dongo and Andrea Adelmo Della Penna. Coronavirus, Omega 3 and the immune system. GIFT(Great Italian Food Trade), 4/13/20, https://www.greatitalianfoodtrade.it/salute/coronavirus-omega-3-e-sistema-immunitario
(4) Dario Dongo (2020) Covid-19, abc. Volume I – People. Available at: https://www.greatitalianfoodtrade.it/covid-19-abc-volume-i-persone_1
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
Graduated in Food Technologies and Biotechnologies, qualified food technologist, he follows the research and development area. With particular regard to European research projects (in Horizon 2020, PRIMA) where the FARE division of WIISE Srl, a benefit company, participates.
