The human immune system is like your personal army that carries out preventive measures or triggers all types of responses to fight an existing infection. Immunology has weapons on multiple fronts – our skin, mucosae and substances that cover them are the first line of defence. These structures form a barrier that considerably prevents harmful pathogens from entering and infecting the body. The key mechanism that provides effective protection is the antibodies’ ability to distinguish cells that are part of the body from harmful microorganisms and pathogens.
It is said that immunity is in the gut. And rightly so. Our bacterial flora, which is a major component of our immune system, is fed to a large extent by what we eat. To work properly, that internal defence needs the right chemical compounds, so it is a good idea to ask yourself a question: what should we add to our diet to make our body stronger?
Vitamins C, A and D
Those organic chemical compounds are particularly important for our immune system because they take part in multiple key biochemical changes. What’s interesting, human body does not produce them on its own in sufficient amounts, which means that you need to get them from food or with supplements.
Vitamin C (ascorbic acid)
Vitamin C is definitely the most frequently mentioned vitamin in the context of immunity. And rightly so. Vitamin C is good for alleviating symptoms of the lower respiratory tract infections, enhancing wound healing, and many other things. It has also been proven that prophylactic intake of vitamin C shortens a common cold duration by 14% among children and by 8% among adults. However, the most spectacular effects have been observed among athletes – thanks to regular supplementation, they cut down the number of actual infections by as much as a half. The following foods have the highest amounts of vitamin C:
- citrus fruits, such as: kiwi, orange, lemon, guava, grapefruit
- vegetables: brussels sprouts, broccoli, cauliflower, sweet paprika, chili peppers, parsley, kale
- other fruit: kakadu plums, acerola cherry, rose hips, blackcurrant, papaya fruit, pineapple and strawberries
Vitamin A
Vitamin A helps the cells in our immune system to specialise; consequently, the body gets better in recognising foreign particles of bacteria and viruses. Just like vitamin C, vitamin A lowers cancer risk and improves the cells’ ability to regenerate. The body also needs it to regulate the process of growth and vision.
Vitamin A is best absorbed with foods and it comes in two forms:
- Retinol – it is found in animal sources, such as: eggs, shark liver oil, dairy products, including: cheese, butter, quark and natural yoghurts
- Beta-carotene – it is found in vegetables and fruit, especially in: broccoli, salads, kale, parsley, dill, spinach, apricots, peaches, mangoes, peppers and tomatoes
Vitamin D
Many experts consider vitamin D to be the most important vitamin for our health; it is essential for keeping balance in many areas of our body. It stabilises the work of the cardiovascular system and helps the heart to work correctly. It facilitates the growth of strong bones and teeth, and vitamin D supplementation supports the treatment of many diseases, including but not limited to the following: Hashimoto’s disease, hypothyroidism, psoriasis, diabetes and inflammatory bowel disease.
Most importantly, it activates the creation of the immune system cells and boosts it to work more effectively. Vitamin D is often dubbed the “sunshine vitamin” because 80% of vitamin D is produced as a result of skin synthesis following exposure to UV light. As for dietary vitamin D, it is mainly present in animal-based products, such as:
- fish, particularly: eel, herring, sprat, trout, salmon, sardine, mackerel
- dairy, primarily: butter, cheese, such as feta cheese, Cheddar cheese, Parmesan cheese, Emmental cheese, fatty quark, goat milk and sheep milk, natural yoghurts and natural kefirs
- eggs, specifically chicken egg yolks
Probiotics and prebiotics
A strong gut microbiome, or our personal bacteria and viruses, is an extremely important element that prevents infections. Myriads of those natural micro-inhabitants make up for more than 70% of resources within our immune system. The beneficial functions of our bacterial flora include the following, among others: sealing the gastrointestinal tract, which strengthens the physical barrier of the intestines, and producing anti-bacterial substances which limit the growth and spread of the pathogens.
They are also supposed to prevent flu infections, and – what’s equally important – they are good for our well-being. We can support those beneficial microorganisms in two ways:
- by providing beneficial bacteria in the form of probiotics, for example, by getting the right preparations or the right foods, such as: yoghurts, kefirs, kombucha, sauerkraut, pickles, miso, tempeh, kimchi, sourdough bread and certain kinds of cheese
- by taking foods that will support the bacterial flora that already exists in our gut (i.e. as a prebiotic). Those products include: asparagus, potatoes, onions, garlic, bran, oats, barley, bananas, legumes, including beans, as well as Jerusalem artichoke, dairy products and honey
Minerals
Just like vitamins, minerals are essential if you want to stay healthy and immune. However, our body does not produce them on its own, which means that their quantity in our body depends on our diet or additional supplementation. The most important minerals include:
Zinc
Zinc is called an element of health because it is indispensable for the correct functioning of the hormones secreted by thymus, which has a strong impact on the effectiveness of the immune system. This micronutrient also plays an important role in wound healing and in thyroid functioning. Zinc deficiency leads to faster ageing of the immune system, which increases the susceptibility to all types of infections. The following products are rich in zinc:
- animal products, such as: seafood, particularly mussels (oysters and moules), fish, red meat and giblets
- plant-based products: nuts, cereals, legumes, seeds and wheat germs, shitake mushrooms, buckwheat groats, white beans and peas
Iron
Just like zinc, iron is essential for the production of lymphocytes and antibodies. It slows down the body ageing processes and helps maintain an adequate amount of free radicals. It takes part in the creation of reactive forms of oxygen that kill the pathogens. Iron deficiency leads to anemia, and excessive iron can lead to overproduction of harmful bacteria and parasites – therefore, you need balance in case of this mineral. Iron is best absorbed with vitamin C. Dietary iron has two forms:
- heme iron, which is mainly found in animal-based products: seafood, fish (particularly tuna, mackerel, sardines), red meat and giblets, meat products (including pates and kishka)
- nonheme iron, which is found in plant-based products, such as: sesame, cocoa, seeds (particularly sunflower seeds and pumpkin seeds), flaxseed, oat flakes, parsley, tofu, legumes (mainly: lentils and chickpea), almonds, hazelnuts and buckwheat.
Fatty acids
Fatty acids, including in particular omega-3 and omega-6 fatty acids, are the essential building blocks of our cells. They help the cell membrane work better and improve all vital processes. What is important in terms of immunity, the fatty acids increase the production of lymphocytes and lower the quantity of inflammatory molecules. People who suffer from infections or wish to prevent infections in the future will benefit from taking omega fatty acids. We can supplement that extremely important ingredient by eating:
- fish, particularly: salmon, herrings, sprat, mackerel, carp and trout
- vegetable oils, such as: flaxseed oil, peanut oil, rapeseed oil, soybean oil, rapeseed and soybean oil, or seaweed oil
- nuts, including in particular: walnuts, Brazil nuts and almonds
- chia seeds, hemp seeds, flaxseed, pumpkin seeds, poppy seed and sesame
- bird eggs
- soy products
Take time to prepare a healthy menu – it is an excellent investment into your health. Naturally, building immunity is a process that takes time, patience and perseverance. However, by adding the above products to your diet, you should notice a difference within just a few weeks – after all, our immunity depends on the strength of our immunity system. So, if you want to enjoy a healthy life free from diseases, look for recipes that contain the above ingredients.