The immune system is the mechanism by which the body defends itself against aggressions. It is therefore essential to protect and strengthen it, so let's try to understand how lifestyle and diet can contribute to the health of our immune system.
Stress, mind body techniques
Mind body medicine focuses on the union between mind, body and brain and uses disciplines such as yoga, tai chi, listening to music or meditation. These techniques are based on the idea that mental state affects body health. In fact, what has been observed is that if a person is able to relax the mind then there is also an improvement in the functioning of the immune system. In fact, following a session of yoga, meditation or tai chi has made possible to observe a balancing action of the immune system, that becomes more active and responsive in case of external attacks (Wahbeh et al, Open Complement Med J., 2012 - Falkenberg et al, J Behav Med, 2018). So these techniques help to restore calm and relaxation in case of stress, but is stress always negative for the immune system? According to scientific studies, only chronic stress increases chronic inflammation and unbalances the immune response. And it is precisely this stress that must be counteracted with the techniques seen in this paragraph. On the other hand, there is good stress, and it is the stress that lasts from a few minutes to a few hours, this stress instead increases the ability to adapt to the surrounding environment as it stimulates all the body's survival techniques. In this scenario, both the innate immune response, which is the first response to the pathogen invasion, rapid and poorly specialized, and the adaptive, secondary response that has the ability to recognize the pathogen and understand if we’ve already been exposed to it previously, are increased ( Dhabhar et al, Immunol Res, 2015). So we should not think that only by avoiding all types of stress the immune system is able to work properly. The events, problems, emotions and obstacles happen continuously, they should be accepted knowing that the body is able to adapt and that precisely these moments help us, indeed, to fight more effectively the external aggressions to the health of our organism.
Diet also plays a very important role in the functioning of the immune system. In fact, our defenses require energy to function properly and effectively and this is supplied by diet or, when it is not sufficient, by the body's storages. So insufficient nutrition also affects the functioning of the immune system. But the diet is also important to give the body some substances that serve to keep the immune system active and to reduce the levels of chronic inflammation, which, when prolonged over time, weakens the immune system. For example, the amino acid arginine, contained in fish, pumpkin seeds, peanuts and walnuts, is essential for the production of nitric oxide by macrophages, which are cells of the immune system that use nitric oxide to fight inflammation and to block the proliferation of pathogens (Tripathi et al, FEMS, 2007). Vitamin A, contained in leafy greens, sweet potatoes, carrots but also egg yolk, and zinc, contained in whole grains, oilseeds and legumes, also stimulate the immune system's response. Vitamin E, contained in almonds, peanuts, sunflower seeds, olive oil but also avocado, has an important role in modulating the immune response. But the diet is also important to maintain a healthy intestinal microbiota, on which the functioning of the immune system depends, so it is important to include in the diet probiotic foods, present in kefir, a type of fermented milk, in yogurt where indicated, tempeh or sauerkraut, and prebiotics, which help to grow good bacteria in the intestine and can be found in artichokes, leeks, onions, garlic but also wheat and bananas (Childs et al, Nutrients, 2019).
Herbs and spices
Curcumin is the active ingredient in turmeric, the yellow and fragrant spice studied a lot by science. Curcumin shows anti-inflammatory properties and results able to modulate the immune response, just like resveratrol, contained for example in grapes, red wine and peanuts. Other anti-inflammatory and antioxidant substances useful for the proper functioning of the immune system are the epigallocatechin gallate of green tea, the quercetin that we find in capers, broccoli, red onion, berries and apples, but also the capsaicin of hot pepper (Jantan et al , Front Plant Sci, 2015).