Apart from vegetables, fruits, and beans there are other foods like nuts, seeds, tea and spices which help in immunity against infections. Deficiencies of protein and some amino acids, as well as vitamins A, E, B6 and folate are associated with weakened immune system. In contrast, polyunsaturated fatty acids, iron, and vitamin E improve immunity. Trace elements like zinc, selenium and copper modulate immune responses through their critical role in enzyme activity. Fibre helps our gut bacteria to thrive, controlling our immune response remotely.
Nuts and seeds
Seeds like flaxseeds, sesame seeds, pumpkin seeds and nuts like almonds/walnuts/pistachios are full of good proteins, fibre, Vitamin E, omega 3 fatty acids. Apart from packing maximum nutrition in a small package, they have anti-inflammatory effect on the body. Flaxseeds and chia seeds contain 35-40% fats, of which 60-70% is ALA (Alpha lipoic acid), a fatty acid which is converted into the most potent anti-inflammatory omega 3 fatty acids in the body. These are the good fats which decrease inflammation but cannot be synthesized by our body. The protein, fibre, vitamin E and phytonutrients are the bonuses, beneficial for gut and heart health.
Nut consumption reduced incidence of coronary heart disease and gallstones in both genders and diabetes in women in many studies. Evidence also suggests beneficial effects on hypertension, cancer, and inflammation. Like seeds they are rich in proteins, Omega 3 fatty acids, Vitamin E and phytonutrients, leading to better immunity. The percentages may vary in different nuts, but take a few daily – the benefits are tremendous.
You can add nuts to yogurt, sprinkle them on salads or cereals, add them to smoothies or just eat them with water. Remember to chew them well or have them ground.
Tea
Rich in catechins and many other polyphenols, tea has multiple effects on the human body. Green tea polyphenols were documented for their antioxidant, anti-inflammation, anti-cancer, anti-microbial and beneficial effects on heart disease, weight and brain function.Black tea and oolong tea are not far behind. However, because of the caffeine content, it is better to limit the intake to 2-3 cups a day. Milk may decrease the content of some phytonutrients, but the jury is not there yet. Enjoy your tea, but avoid taking it extremely hot, can be harmful for the lining of food pipe and stomach.
Spices
Spices have been used across all cultures to enhance the taste of food. Turns out they do much more than that. They are known to have many nutrients, which even in small doses can benefit the human body.
Turmeric is a superfood. Robust research on Curcumin, the active ingredient, has shown anti-inflammatory properties. It is regularly added to food in parts of Asia – especially India. It has anti-inflammatory, anti-microbial, insecticidal, radio-protective, and anti-cancer properties. It’s absorption from gut is poor, so combine it with black pepper which contains piperine which increases absorption of curcumin by 2000-fold.
Gingerol in ginger is reported to have biological properties such as antioxidant, anti-inflammatory and anti-cancer properties.
There are many other spices like cinnamon and cloves, known to have similar benefits.
While there are many more spices, use them in your food daily to reap the health benefits. Moderation is the key as too much can be harmful too.
Probiotics containing good bacteria, which are already present in our gut are our helpers in the fight against viral infections. Curds and buttermilk, a staple in India have these in abundance. Other cuisines have Kimchi, Sauerkraut, Kombucha, Miso etc. Fibre is food for them, as mentioned earlier. Have probiotics daily, their benefits go beyond strengthening the immune system.
Sunlight is not something we eat but absorb. It is the main source of Vitamin D, an essential vitamin for better immunity apart from being important for bones. Our exposure to sun has decreased during lockdown, so people with known Vitamin D deficiency should consult a physician for replacement.
Many phytonutrients have been studied for their effect against many viruses. Myricetin, found in red grapes, tea, parsley, and blueberries has been studied for its effect on SARS CoV-1. Turmeric and black ginger (found in far east) have shown some role in respiratory infections like Flu (H5N1). While it is too early to have specific data on the effect of food on Coronavirus, foods which are known to have high antioxidant and anti-inflammatory effects on the body are our weaponry in the war against Coronavirus.
References
Enhancing immunity in viral infections, with special emphasis on COVID-19: A review, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7161532/?report=classic
Nutritional value of flaxseeds, https://www.ncbi.nlm.nih.gov/pubmed/22888664
Optimal Nutritional Status for a Well-Functioning Immune System Is an Important Factor to Protect against Viral Infections, https://www.ncbi.nlm.nih.gov/pubmed/32340216
Targets of curcumin, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3025067/
Flavonoids: promising natural compounds against viral infections, https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7087220/