Irish Study Shows That Anti-Inflammatory Diets Comprising Of Mediterranean Cuisine, Vitamin C, D, Omega-3 Fatty Acids And Zinc Helps In COVID-19

Researchers from University of Limeric-Ireland have in a news study found that anti-inflammatory diets comprising of Mediterranean cuisine, Vitamins C, D, Omega-3 fatty acids and Zinc helps in COVID-19 specially in terms of preventing disease severity.

 
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), otherwise known as COVID-19, has challenged healthcare systems at an international level.
 
COVID-19 suppresses the immune system by causing a systemic inflammatory response, also known as cytokine release syndrome, leaving COVID-19 patients with high levels of proinflammatory cytokines and chemokines.
 
Nutrition’s function in the respiratory and immune systems has been investigated in much research, and its significance cannot be overstated, as the nutritional status of patients has been shown to be directly connected with the severity of the disease. Key dietary components such as vitamin C, D, omega-3 fatty acids, and zinc have shown potential in their anti-inflammatory effects, as well as the famous Mediterranean diet.
 
The study found that the use of anti-inflammatory dietary approaches does to a certain degree prevent Sars-CoV-2 infections and even lessen COVID-19 effects.
 
The study findings were published in the peer reviewed journal: Diseases.
https://www.mdpi.com/2079-9721/9/4/76
 
The ongoing COVID-19 pandemic has put a significant burden on many countries' socioeconomic and healthcare systems, with more than 247.6 million infections and over 5.01 million deaths recorded to date.
 
Despite the fact that COVID-19 remains asymptomatic or mildly symptomatic in the majority of infected individuals, it may cause severe life-threatening consequences in susceptible people, including older adults, immunocompromised patients, and those with comorbidities.
 
To date, the primary hallmark of severe COVID-19 is hyperinflammation characterized by excessive secretion of cytokines and chemokines. As evidenced in the literature, interferon-gamma, interleukin (IL)-1, -6, and -18, and tumor necrosis factor (TNF) are the major cytokines involved in COVID-19-related immunopathological conditions. Such hyperactivation of the immune system is collectively known as "cytokine storm," which subsequently leads to immune cell apoptosis, delayed viral clearance, alveolar barrier disruption, and pulmonary injury.
 
However, it is well-documented in the literature that a healthy diet is important for the proper functioning of the immune system.
 
It has been found that individuals with poor nutritional status appear to have weakened immune systems, making them more susceptible to viral infections.
 
Considering the pathophysiology of COVID-19, anti-inflammatory diets are expected to reduce immunopathological burdens of the disease.
 
The study team included all articles that studied the impact of dietary micro/macronutrients on COVID-19-related hyperinflammation.
 
The team specifically selected clinical trials, randomized controlled trials, meta-analyses, and review articles published between January 2020 and June 2021. Aft er excluding non-human studies, preprint articles, and non-English articles, they finally selected and discussed 17 studies in the current review.

The research findings selected in the review reported that COVID-19 patients with nutrient deficiency take longer to recover.
 
Furthermore, it was found that the majority of hospitalized patients appeared to have at least one nutrient deficiency. As nutritional interventions for COVID-19 management, the studies primarily focused on some critical anti-inflammatory dietary components, including vitamins C and D, zinc, and omega-3 fatty acids, as well as the Mediterranean diet.
 
The Mediterranean Diet
 
Typically, the Mediterranean diet comprises of plenty of vegetables and fruits, legumes, fish, and olive oil, is known to have potent anti-inflammatory, immunomodulatory, antioxidant, and anti-thrombotic properties. It is well-documented that the Mediterranean diet is highly effective in managing cardiovascular, pulmonary, and metabolic diseases.
 
Pertaining to COVID-19 management, studies have shown that the Mediterranean diet effectively reduces the length of hospital stay and mortality rate in COVID-19 patients aged above 65 years. Moreover, the Mediterranean diet has been known to reduce the risk of SARS-CoV-2 infection as well as the short-term and long-term complications associated with COVID-19.
 
The Importance Of Vitamin D
 
The anti-inflammatory, antiviral and immunity-boosting properties of vitamin D are well-documented in the literature. In addition, vitamin D reduces the production of proinflammatory mediators by minimizing the production of T-helper 1.
 
It has been shown that in severely ill COVID-19 patients, vitamin D supplementation reduces the duration of intensive care unit (ICU) stay.
 
Numerous other studies have shown that COVID-19 patients with vitamin D deficiency tend to have higher mortality rates and that vitamin D supplementation can reduce long-term immunological outcomes of COVID-19, such as prolonged elevation of IL-6 and interferon-gamma levels.
 
Though further research is needed to conclude any therapeutic benefit of vitamin D against COVID-19, most studies indicate that the extent of therapeutic benefits depends on the patient's prior vitamin D status. Thus, adequate vitamin D intake is generally recommended to prevent deficiency. The recommended dietary allowance of vitamin D is 600–800 IU/day.    
     
Merits Of Vitamin C

To date, the antioxidant property of vitamin C is well-documented. It acts as a cofactor in many biosynthetic pathways and facilitates antibody production. Moreover, dietary intake of 1 gm of vitamin C per day is known to reduce the production of proinflammatory cytokines (IL-6, TNF, and C-reactive protein) and increase the production of anti-inflammatory cytokines (IL-10).
 
Interestingly In COVID-19 patients, intravenous infusion of high-dose vitamin C has been shown to reduce the duration of ICU stay and mortality rate. It also reduces the progression of COVID-19 symptoms. A phase 2 interventional study is currently going on to study the impact of vitamin C supplementation in COVID-19 patients. https://www.sciencedirect.com/science/article/pii/S0378512220303467
 
https://pubmed.ncbi.nlm.nih.gov/30934660/
 
https://www.mdpi.com/2072-6643/13/6/1924
 
https://pubmed.ncbi.nlm.nih.gov/33638944/
 
https://pubmed.ncbi.nlm.nih.gov/33420963/
 
https://clinicaltrials.gov/ct2/show/NCT04395768
 
At present, the recommended daily allowance of vitamin C for adults is 90 mg/day. Although short-term use of vitamin C is safe, prolonged intake of high-dose vitamin C could induce adverse health conditions, such as oxalate kidney stone formation.
 
Another Helper- Omega-3 Polyunsaturated Fatty Acids
 
It has been found that Omega-3 fatty acids such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) exhibit the ability to inhibit proinflammatory cytokine production and produce less inflammatory pro-resolving lipid mediators, including prostaglandins, thromboxanes, protectins, and resolvins.
 
Importantly, in SARS-CoV-2 infection, omega-3 fatty acids might play a beneficial role by regulating the lipid raft fluidity and subsequently disrupting the formation of spike – angiotensin-converting enzyme 2 (ACE2) complex. Currently, a clinical trial is underway to study the impact of EPA intake on SARS-CoV-2-infected patients.  
 
An Essential Mineral-Zinc
 
The mineral Zinc is a crucial component required for immune cells and the proper functioning of T-helper and cytotoxic T cells. In COVID-19 patients, zinc supplementation has been shown to exhibit a potential anti-inflammatory response. Moreover, the mineral has been shown to reduce symptom intensity in SARS-CoV-2-infected patients.  
 
The study team concluded, "No single diet or food item has been proven to prevent COVID-19 infections. Regardless, supplements have received a great deal of interest from both the public and the scientific community as an effective and low-cost method for controlling or mitigating COVID-19 infections. However, despite evidence that some supplements can affect outcomes in other respiratory tract infections, such as reduced inflammation marker levels, shortened ICU stay lengths, and incidence of infections, it is still unknown whether dietary supplements or nutraceuticals can therapeutically alter patient outcomes against COVID-19. Furthermore, there is little research linking them with the prevention of COVID-19. With the aid of larger-scale COVID-19 clinical trials and investigations, the therapeutic or preventative functions of a nutrient approach will likely be clarified. Until then, the public should focus on immunization through vaccination and prioritize appropriate nutritional status, and encouraging an active lifestyle."
 
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