The Turin Academy of Medicine points to the key role of vitamin D in preventing coronavirus and more serious complications. Without losing sight of proper nutrition, vitamin C and exercise.
It should be clarified preliminarily that to date there is no scientific evidence of effective therapies to address SARS-Cov-2 infections. Social precautions (no gatherings, minimum interpersonal distance, use of masks) and hygiene (thorough and frequent hand washing, sanitization of surfaces) remain the only effective means of preventing transmission and mitigating infection.
Coronavirus, oxidative stress and prevention
Reducing oxidative stress-that is, the condition of imbalance between oxidant and antioxidant factors in the body’s cells-is crucial to reducing inflammatory phenomena and strengthening immune defenses. (1) And it is therefore that the 2008 Nobel Prize winner in Medicine Luc Montagnier-already at the dawn of the coronavirus emergency, as it turned out-recommended the intake of foods and supplements rich in antioxidants, vitamins C and D. Prevention can thus be guided by three pillars:
– proper nutrition. The Mediterranean diet, which in recent days we have also proposed in the terms of
tips for weekly shopping in the Covid era
, offers everything we need. (2) With attention also paid to the specific nutritional needs of the over-65s,
– Adequate intake of vitamins. By definition, vitamins are not synthesized by humans and must be taken through the diet. They are divided into groups and identified with the letters of the alphabet. Since each of them exerts a specific action, it is important to avoid deficiencies without, however, exceeding dosages out of proportion, (3)
– physical activity. Regular exercise, including at home and in close proximity, is another useful tool for maintaining fitness and health, including reducing oxidative stress. (4) And it is helpful in stimulating good mood, which is equally valuable since depression-in worsening quality of life-contributes to increased oxidative stress and lowered defenses. (5)
The role of vitamin D in the prevention and treatment of Covid-19
Vitamins D and C are often cited in this time of emergency as possible allies in the battle against coronavirus. Vitamin D, in particular, is being studied to assess its possible influence in reducing the chances of contracting the SARS-CoV-2 virus. Professors Giancarlo Isaia (professor of geriatrics and president of the Turin Academy of Medicine) and Enzo Medico (professor of histology at the University of Turin), partly in light of recent recommendations from the British Dietetic Association, therefore suggest that the medical community consider the following.
Adequate levels of vitamin D must be ensured in the population, ‘but especially in those already infected, their relatives, health care personnel, the frail elderly, residents of assisted living residences, those in seclusion, and all those who for various reasons do not get adequate exposure to sunlight.’ (6)
Numerous scientific evidences show in fact:
– The active role of vitamin D on modulation of the immune system,
– Vitamin D’s ability to help reduce the risk of respiratory infections of viral origin,
– Vitamin D’s ability to counteract hyperinflammation lung damage,
– the association of hypovitaminosis D with a wide range of chronic conditions that can reduce life expectancy in older people. (6)
Patients hospitalized for COVID-19–according to initial data collected in recent weeks in Turin–then show a ‘very high prevalence of hypovitaminosis D.’ The Turin Medical Academy therefore recommends exposure to sunlight (including at home, on balconies or windows), consumption of vitamin D-rich foods and, where appropriate, administration of specific pharmaceutical preparations under medical supervision.
‘Sunshine, not food, is where most of your vitamin D comes from. So even a healthy, well-balanced diet, which provides all the other vitamins and goodness you need, is unlikely to provide enough vitamin D‘ (
British Dietetic Association
).
Vitamin D plays a very important role in the prevention of various diseases. And there is a marked lack of it in Italy in the over-65 age group (in 76 percent of women). This aspect is very important for elderly people, who are generally more deficient in this vitamin. (7) Exposure to sunlight, diet and the use of supplements are the means to be used to increase the concentration of the vitamin in the body.
During periods of domestic seclusion–as more generally, during winter–lower sunlight results in less synthesis of this vitamin, making people more susceptible to the onset of disease. (8) The most important and biologically active form of vitamin D is D3 (cholecalciferol), the only one by the way that is synthesized in sunlight. This is followed by D2 (ergocalciferol), which also has influence on health. (9)
The role of vitamin C
At present there is a lack of specific studies on the ability of vitamin C to help prevent coronavirus infections and possible complications. A recent clinical trial, nonetheless, reports the efficacy of vitamin C in mitigating the mortality of individuals with viral infections causing respiratory crisis. (10) After all, the antioxidant properties and health benefits of this vitamin, including with regard to the immune system, are well known and established.
EFSA(European Food Safety Authority) has in fact validated the scientific substantiation of several health claims, subsequently approved by the European Commission, related to vitamin C intake. These include the following.
‘Vitamin C contributestothe maintenance of normal function of the immune system during and after strenuous physical exertion’ (beneficial effect is achieved by daily intake of 200 mg in addition to the recommended daily intake of vitamin C)‘ (EU reg. 432/12, Annex).
Gallery – Foods rich in vitamin D (fig.1) and vitamin C (fig.2). Amount of vitamins-in milligrams, mg, or micrograms, mcg-per 100 grams of food. (11)
Food sources of vitamin D
The primary dietary sources of vitamin D3, are foods of animal origin:
– Fish oil (the richest) and fatty fish,
– egg yolk,
– butter,
– whole milk,
– Pork and beef liver,
– molluscs.
The bioavailability of vitamin D in these foods is high because the vitamin is lipophilic and interacts well with fats. It is deposited right in the adipose tissues, before being translocated to the sites where it then performs its proper functions. Vitamin D2 is found in foods of plant origin, especially mushrooms. (12)
Food sources of vitamin C
Orange is universally known as a source of vitamin C, but it is not the richest food. Vitamin C is contained in several plant foods:
– Kiwi, black currant, lemon (fruit),
– Broccoli, peppers, lettuce, spinach (vegetables),
– new potatoes (tubers).
It is a hydrophilic vitamin, meaning that it is best distributed in water. Vegetables should therefore be undercooked, as vitamins degrade with prolonged heat and are lost in the cooking water. (12)
Dario Dongo and Andrea Adelmo Della Penna
Notes
(1) Bjørklund et al. (2017).
Role ofoxidative stress and antioxidants in daily nutrition and human health
. Nutrition 33:311-321, doi: 10.1016/j.nut.2016.07.018
Ursini F, Maiorino M, Forman HJ.
Redox homeostasis: The golden mean of healthy living.
Redox Biol. 2016;8:205-215. doi:10.1016/j.redox.2016.01.010
(2) Motarjemi et al. (2014). Encyclopaedia of Food Safety – Vol.1. Elsevier; Academic Press; pp. 94; ISBN:9780123786128
(3) Zhang et al. (2018). A review of the extraction and determination methods of thirteen essential vitamins to the human body: an update from 2010. Molecules 23(6): 1484, doi: 10.3390/molecules23061484
(4) Pingitore et al. (2015). Exercise and oxidative stress: Potential effects of antioxidant dietary strategies in sports. Nutrition 31:916-922, doi: 10.1016/j.nut.2015.02.005
(5) Marx et al. (2017). Nutritional psychiatry: the present state of the evidence. Proceedings of the Nutrition Society 76:427-436, doi: 10.1017/S0029665117002026
(6) Giancarlo Isaia and Enzo Medico,
Possible preventive and therapeutic role of vitamin D in the management of COVID-19 pandemic.
. University of Turin, paper 25.3.20 https://www.unitonews.it/storage/2515/8522/3585/Ipovitaminosi_D_e_Coronavirus_25_marzo_2020.pdf
The authors add that ‘administration of the active form of Vitamin D, Calcitriol,intravenouslyin patients with COVID- 19 and with particularly impaired respiratory function could also be considered‘
(7) Isaia G, Giorgino R, Rini GB, Bevilacqua M, Maugeri D, Adami S. (2003). Prevalence of hypovitaminosis D in elderly women in Italy: clinical consequences and risk factors. Osteoporos Int. 2003;14(7):577-582. doi:10.1007/s00198-003-1390-7,
Waterhouse et al. (2014). Environmental, personal, and genetic determinants of response to vitamin D supplementation in older adults. The Journal of Clinical Endocrinology & Metabolism 99 (7): 1332-1340, doi: 10.1210/jc.2013-4101
(8) Engelsen (2010). The relationship between ultraviolet radiation exposure and vitamin D status. Nutrients 2(5):482-95, doi: 10.3390/nu2050482
(9) Grant et al. (2020). Vitamin D supplementation could prevent and treat influenza, coronavirus, and pneumonia infections. Preprints, doi:10.20944/preprints202003.0235.v1
(10) Arabi et al. (2020). Critical care management of adults with community-acquired severe respiratory viral infection. Intensive Care Med. 46:315-328 https://doi.org/10.1007/s00134-020-05943-5
(11) Nutritional values of foods. http://www.valori-alimenti.com/
(12) Belitz et al. (2009). Food Chemistry – 4th revised and extended edition. Springer; pp. 406-410; Hardbook. ISBN: 9783540699330, e-ISBN: 9783540699347
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.
