An overview of dietary habit and food components to strengthen our immune system against COVID-19

COVID 19 scenario at present and us:

After spending twenty-one days of lockdown we are currently at the brink of extending a restricted lifestyle for another fifteen days. Every day we are witnessing the assault of global humanity in the form of death or severe ailment of an ever-increasing number of people. With no proper immunization currently available to overthrow the virus, our only option is social distancing to prevent the spread of the disease. As a consequence, our daily life has lost its normal rhythm, leaving us unstable and uncertain in every aspect of life: be it personal or professional. Being confined in isolation, either with family or without, we are witnessing a critical phase of social, economic and medical insecurity that has left us worried about the well-being of our family members and associates. The biology of COVID-19 is gradually unraveling and now we know that a weaker immune system predisposes an individual to this respiratory disorder. That is why people with older age and associated comorbidities such as diabetes, hypertension and cardiovascular disease are at higher risk.

But we must fight back.

However, we need to keep the stress at bay and win over this period of adversity with a positive attitude. It will not only help us to survive and cheer up with our near and dear ones, but also to optimize our performance, engagement, and focus in life. In the absence of well-defined medicaments, we should adopt some natural heal to improve our immunity so that we can fight against the crisis on our own. In isolation, an important way to do so is to avail a healthy nutritious diet that is easily available, nutritious as well as immunologically beneficial.

Secluded lifestyle and the temporary closing of businesses may affect normal food-related practices and availability. In midst of the limitation in access to purchase and variability of food products in these hot summer days, let us identify some easily available foods and food practices that will help in making our immunity strong and bring variation in our diet regime.

First and foremost: Food habits

• Avoid over-purchasing: WHO observed that panic buying may have adverse consequences like an increase in food prices, overconsumption of food and unequal distribution of products. It is better to plan our meal, be considerate about others and use short shelf-life food to bring variation in food habits and also to avoid food waste.

• Home-cooked family meal: As we are spending considerable periods at home we can try a variety of healthy and delicious recipes that can be found online with accessible ingredients. It will help to manage time also. Family meals are a golden opportunity to spend quality time with each other, have fun and strengthen the bonding.

• Safe food-handling: In the well-sanitized kitchen with clean utensils, we should cook food thoroughly using safe water and ingredients that are properly washed. Frequent washing of hands with soap following WHO guidelines must be followed. Raw food should always be separated from cooked food. Food wastes should be disposed of in a sanitary way.

• Smoking and alcohol consumption to be avoided: Smoking and alcohol are not a necessary part of our diet and not part of a healthy lifestyle. Rather this is a perfect time to give up the habits of smoking and alcohol consumption. As smoking enhances inflammation, impairing ciliary movement in lungs the propensity of the immune-deficient condition and autoimmune disorders increase. Alcohol consumption disrupts the gut barrier by damaging epithelial cells, and immune cells like T cells, macrophages and neutrophils and facilitating leakage of microbes into the circulation. Thus it enhances the chance of bacterial and viral infections and also an autoimmune response by inhibiting cytokine production. Therefore it is better not to make our immune system more susceptible at the time when it needs to gear up.

• Avoid overeating and do the physical exercise: Being at home for extended periods, especially with limited activities can also lead to overeating and hence obesity. Physical exercise for at least 30 minutes will keep us healthy and refresh our minds.

• Frequent hydration: At least 8-9 glasses of safe water are advised for consumption so that our mucous membranes remain hydrated lowering the chance of catching a cold and our innate immune system is strengthened. But frequent consumption of strong coffee, strong tea should be avoided as it may disturb our sleeping habits.

• Say no to excess fat, sugar, and salt: WHO recommends a maximum salt intake of 5 g/day and also less than 5% of total energy intake for adults coming from free sugars. While a high-salt diet is one of the major risk factors in the development of hypertension, kidney injury, and cardiovascular diseases, excess of sugar can be linked to obesity and several metabolic diseases, including diabetes mellitus type II, NAFLD, and cardiovascular diseases. WHO also endorses limiting total fat intake to less than 30% of total energy intake, of which no more than 10% should come from saturated fat which otherwise will disrupt the intestinal barrier by attracting pathogenic bacteria.

• What are the food choices?
  Good health is largely affected by nutrients. Fresh products, especially fruits, vegetables, and reduced-fat dairy products should be prioritized over other types of fruits. A rainbow of nutrients, i.e., a colorful source of food is considered to be an ideal example of a balanced diet that we may narrow down to three colors similar to our National flag – saffron/orange, white and green.

•  Orange food: In the orange group we consider all red, yellow, orange-colored fruits and vegetables. In this season we can easily get papaya, oranges, pomegranates, red onions, sweet potatoes, tomatoes, carrots, mangoes, pumpkin, and watermelon that are rich in Beta-carotene, zeaxanthin, flavonoids, lycopene, potassium, glutathione and vitamin C, A, B6. These nutrients contribute to immunity build-up by lower blood pressure, reduce LDL cholesterol levels, scavenge harmful free-radicals, encourage alkaline balance and strengthen gut microbiota. Citrus fruits help in WBC production. A healthy gut microflora ensures proper functioning of gut-associated lymphoid tissues that contain a major fraction of our immunocytes.

• White food: A wide variety of food ranging from fruits and vegetables like bananas, garlic, ginger, potato, etc. and whole-grain products like oats, barley to cereals like rice, wheat and dairy products like milk, home-made curd are included in this category. Poultry products also come under this category. White food of plant origin contain β-glucans, EGCG, SDG, and lignans that provide powerful immune-boosting activity by activating natural killer B and T cells. Garlic’s immune-boosting properties seem to come from a heavy concentration of sulfur-containing compounds, such as allicin. Vitamin D in home-made curd can enhance natural immunity and the probiotic microorganisms present help to maintain a healthy gut microflora. Proteins, essential amino acids and Vitamin B6 make chicken and egg an essential component in our dining platter to give us protection against flu and other diseases as well as to increase the erythrocyte count. Stock or broth made by boiling chicken bones contains gelatin, chondroitin, and other nutrients helpful for gut healing and immunity.

•  Green food: All green and leafy vegetables and fruits contain nutrients like Chlorophyll, fiber, lutein, zeaxanthin, calcium, folate, vitamin C, calcium, and β-carotene that lower blood pressure and LDL cholesterol levels, normalize digestion time, fight harmful free-radicals, and boost immune system activity.

With all these resources we can prepare different platters that will bring some variations in our present monotonous life and at the same time help build up a strong defense mechanism of our own. Good food practice also encourages positive thinking. So eat well, be optimistic and stay safe. If we stay healthy we can apprehend to overcome this temporary phase of gloominess and start afresh our schedule in the light of hopes and possibilities very soon.