-Deepti Khatuja Assistant manager, Clinical nutrition and dietetics Fortis Memorial Research Institute
Today, the whole world is fighting the covid pandemic. Covid 19 is a respiratory tract illness caused by novel Coronavirus, SARS-CoV-2. Acute respiratory tract infections are the major driver of mortality and morbidity worldwide, as demonstrated by recent COVID-19 and seasonal influenza epidemics. Various studies have shown a strong connection between a good nutritious diet associated positively with innate and adaptive immunity. Hence with the COVID pandemic, everyone is talking about the various foods/ diets that build immunity. Immunity is of 2 types-
Innate Immunity is the nonspecific (will defend against anything and that is identified as foreign or non – self) immunity and is developed fast in minutes and hours. For example- skin, body hair, mucus, secretions etc. On the other hand, Adaptive or acquired Immunity is highly specific (identifies pathogens and differences in molecular structures) immunity and takes days to develop. It includes B cells and T cells.
Lot of factors Influence the person’s immune system like – Age, gender, nutrient status, diet, physical Activity, obesity, alcohol consumption, smoking, stress etc., but most commonly talked in today’s time is DIET.
Lot of researches (e.g. DASH diet – which is rich fruits, vegetables, whole grains and low fat dairy products), have shown the vegetarian/ Plant based diets can reduce the risk of Comorbidities like obesity, Atherosclerotic cardiovascular diseases and Hypertension etc. These comorbidities are disproportionately affected with severe COVID 19 disease and mortality.
Although New research suggests plant based diet may help in lowering COVID-19 severity. A plant-based diet was associated with 73% lower odds of moderate to severe COVID-19 infection in the study. A pescatarian diet, which includes fish but limits or eliminates meat, was associated with 59% lower odds. Compared to those who ate a plant-based diet, those with a low-carb, high-protein diet had nearly four times the odds of moderate to severe COVID-19 infection, according to the study.
The possible reason behind this is- Plant-based diets are rich in nutrients, especially phytochemicals (polyphenols, carotenoids), vitamins and minerals(Vitamins A, C,E, folate, Iron, potassium, magnesium, Zinc), which are important for a healthy immune system. Phytochemicals are bioactive Non nutrient plant compounds which are present in fruits, vegetables, grains and other plant foods and they act as anti-oxidants which protects the cell against oxidative damage and reduce developing certain types of cancers. Micronutrients like vitamins and minerals along with phytonutrients play a crucial role in several metabolic pathways that aid in optimal immune system.
- They enhance the native and adaptive immune Function and prevent infections.
- Regulate immune Function, keep inflammation under control and prevent tissue damage.
- Aid immune memory formation that helps prevent reinfection with the same pathogen.
- Also increases beneficial probiotic bacteria in the intestine, regulate gut microbiota, maintain intestinal integrity and thus reduce the transmission of toxins from the intestine to blood circulation.
Various studies have shown that supplementation of Vitamins A, C, D, E decreases the risk of respiratory diseases and infections such as common cold, pneumonia and also shorten the duration of these illnesses. Also, a diet high in vegetables, but low in processed meat and high-fat dairy, helps people maintain a healthy weight – with obesity long being linked to severe COVID-19. On the other hand Fish is an important source of vitamin D and omega-3 fatty acids, both of which have anti-inflammatory properties.
Although the data is not enough and we need to have more studies for the same.
But the scientific proven fact that cannot be Ignored is that a healthy diet rich in nutrient- dense foods may be considered as a protection against severe COVID 19. Hence having a good healthy balanced diet with good physical activity and reduced stress levels along with proper hydration and sleep patterns is the key for the strong and specific Adaptive immunity which takes days / years to build and prevent infections.
