Exploring the Mediterranean diet as a potential strategy against SARS-CoV-2

By Colin Lightfoot, M.Sc. Infection and ImmunityDec 22 2021Reviewed by Aimee Molineux

Since the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first detected in late 2019, it has resulted in a global pandemic. The public is not immune to SARS-CoV-2 and is therefore vulnerable to the new virus epidemic. SARS-CoV-2 infection usually results in mild disease, according to previous epidemiological and clinical investigations with coronavirus disease 2019 (COVID-19), albeit a small number of individuals suffer severe or critical illness.

Asymptomatic persons are predicted to account for 17.9% to 78% of infected people, whereas about 15% of infected people will have severe disease, and about 5% will get severe pneumonia and acute respiratory distress syndrome (ARDS).

Data from the COVID-19 case fatality rate (CFR) in Italy was recently published, revealing a linear link between the CFR and age. CFRs are less than 0.4 % in patients under the age of 40, 1% in those over 50, 3.5% in those over 60, 12.8% in those over seventy, and 20.2% in those over 80; the overall CFR is 7.2%. SARS-CoV-2 virus levels appear to be similar in asymptomatic, moderate symptomatic, and severe symptomatic individuals, according to new findings, but many other factors influence the disease's course and severity.

There are currently no particular data on the immunological response to SARS-CoV-2, but fresh research has found that a cytokine storm overstimulates the body's immune response to microorganisms as a result of increased inflammatory factor levels.

Due to its anti-inflammatory and immune-modulatory qualities, the Mediterranean diet (MetDiet) has been linked to a lower risk of major chronic diseases in various studies. As a result, the authors believe that the MetDiet could be advantageous to those who have SARS-CoV-2 infection. The findings given in this publication by a group of researchers from various Italian institutions provide nutritional knowledge on the protective effects of a Mediterranean diet against COVID-19 risk.

This study is available on the mdpi* server.

The study

The MetDiet is a way of eating that is based on the traditional meals and drinks of the Mediterranean countries. This nutritional model has been pushed internationally as one of the healthiest eating patterns in recent decades and has been consistently advantageous in terms of longevity. High consumption of unrefined cereals, fruit, vegetables, legumes, and olive oil, moderate use of dairy products and wine, and low meat consumption characterize the MetDiet.

MetDiet and COVID-19-related fatalities were found to have a substantial negative correlation in an ecological investigation of only European nations. The authors discovered that MetDiet adherence was negatively correlated with COVID-19 instances and deaths in 17 Spanish regions and that this connection persisted even after accounting for well-being characteristics. After adjusting for physical inactivity and several confounding factors, the same authors showed a negative relationship between Metdiet adherence and COVID-19-related fatalities across 23 nations (OECD).

Increased levels of several cytokines, mostly of a proinflammatory nature, such as tumour necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), and C-reactive protein (CRP), are associated with COVID-19. As a result, effective treatment techniques could include lowering inflammation to reduce infection risk or to lessen the severity of COVID-19 disease. Several studies have found that the MetDiet has beneficial effects on inflammation and oxidative stress. The good effects caused by MetDiet on persons with inflammatory disorders affecting the respiratory system testify to the stimulating effect induced at the level of the immune system.

Fruits, whole grains, vegetables, fish, polyunsaturated fatty acids (PUFA), and monounsaturated fatty acids (MUFA) have all been shown to reduce inflammation in the body, whereas foods heavy in saturated fat, such as processed red meat, cheese, and dairy, have been shown to increase inflammation. It's possible that the MetDiet's favourable effects are due to its abundance of healthy foods (high in fibre, PUFA, minerals, vitamins, polyphenols, and antioxidants) and lack of fatty foods (high in starch, refined sugar, and trans fatty acids).

Although no one food has the ability to prevent or treat SARS-CoV-2 infection, the Mediterranean diet pattern has a variety of foods and nutrients that may help to improve the outcomes of SARS-CoV-2 infection. Researchers, the general public, and the media are all becoming increasingly interested in this topic. Vitamin D, vitamin C, and selenium have all received attention recently, owing to a relationship between deficiency and the severity of SARS-CoV-2 infection and COVID-19 disease. The possible usefulness of foods and nutrients supplementation as a preventative measure against these illnesses, on the other hand, is a contentious issue. As a result, the population's diet plays a critical role in incorporating all potentially helpful nutrients. For this reason, sticking to MetDiet could be a good way to reach these objectives.

Implications

When reducing SARS-CoV-2 virus susceptibility in the general population is a priority, it may be critical to follow the MetDiet recommendations, which encourage the consumption of foods high in nutrients with antioxidants and anti-inflammatory properties. Even in an emergency, the daily diet of legumes, fruits, veggies, and extra virgin olive oil can be easily followed.

The authors evaluated the most relevant research, concentrating on the potential advantages of anti-inflammatory and antioxidant minerals, vitamins, and components, which may play a critical role in reducing susceptibility to viral infections in all populations during this worldwide pandemic. MetDiet is a naturally supplemented dietary pattern that, when combined with non-smoking and regular physical activity, can lower susceptibility to SARS-CoV-2. As a result, the MetDiet may be regarded a viable nutritional alternative during the global SARS-CoV-2 pandemic.