Immunity diet

Who is it for?

An immunity-boosting diet is for everyone, regardless of age or lifestyle. It is especially recommended for those struggling with recurring infections, fatigue, or lethargy. These are usually caused by a weakened immune system, which can result from quantitative or qualitative malnutrition. Failing to provide enough energy, being underweight, or experiencing sudden weight loss can all weaken the immune system. Even if your caloric intake is sufficient, if your diet lacks nutritional density—such as not enough protein, omega-3 fatty acids, vitamins, or minerals—your immune response may still be compromised.

Importantly, an immunity-boosting diet is not seasonal! It is worth following these principles regardless of the time of year or the prevalence of viruses. Supporting your immune system through proper nutrition is a year-round commitment.

Dietary principles

Our immune health is closely linked to the functioning of our digestive system, which begins in the mouth. Throughout the entire digestive tract, bacteria and viruses encounter initial defense barriers, such as the low pH of stomach acid, proteolytic enzymes, the intestinal epithelium, and the gut microbiome. Furthermore, efficient digestion and absorption processes ensure the bioavailability of minerals and vitamins that directly or indirectly support immune cells.

Therefore, to strengthen your immunity, it is worth incorporating foods rich in specific nutrients that help maintain proper bodily function. These include: magnesium and iron, which reduce feelings of fatigue, as well as zinc and selenium, which help protect cells from oxidative stress. Also extremely important are vitamins, particularly D, A, and C. To maximize your chances of getting all the necessary nutrients and bioactive substances, your diet should be well-balanced and varied. 

Which foods are recommended?

The MultiLife immunity-boosting diet is based on the principles of healthy nutrition. It is further enriched with foods that are concentrated sources of substances essential for strengthening immunity. These include:

• Fatty sea fish, such as sardines, salmon, halibut, mackerel, and herring. These are the best sources of essential omega-3 fatty acids, which have strong anti-inflammatory properties and enhance the immune system's response to pathogens like bacteria, viruses, and fungi. Additionally, fatty fish provide vitamin D, which has a profound impact on the human body.
• Nuts, seeds, and kernels. These are sources of zinc, which plays a role in the maturation of immune cells. A deficiency in zinc impairs immune function, increasing the risk of various infections. Other sources of zinc include oysters, beef, pork, and dried legumes. It is therefore worth including them in your diet. Some nuts and seeds, such as walnuts or flaxseed, are also sources of valuable omega-3 fatty acids.
• Allium vegetables, e.g., onion, garlic, leek, shallot, chives. They contain phytoncides, which have bactericidal and fungicidal properties, helping to fight pathogenic microorganisms. The most active compound is allicin, found in garlic. It exhibits antibacterial, antiviral, and antifungal effects. Furthermore, garlic boosts the body's defense mechanisms by strengthening and regulating cellular immune responses. These vegetables are also rich in vitamins C and E, as well as sulfur, selenium, and dietary fiber. The latter supports the growth of beneficial gut microbiota.
• Fermented vegetables. Recently, the trend of fermenting various vegetables has gained popularity, and almost anything can be fermented—carrots, beets, cauliflower, radishes, garlic, zucchini, and even tomatoes. And rightly so! Because naturally fermented vegetables, in addition to high amounts of vitamin C, contain lactic acid bacteria that support the development of beneficial human gut microbiota, positively affecting the immune system. The fermentation process also increases the quantity, availability, and absorption of nutrients, and boosts antioxidant content.
• Dairy – fermented milk products. Dairy products, such as plain yogurt, kefir, buttermilk, or sour milk, are created through a fermentation process, primarily by lactic acid bacteria. They contain easily digestible protein, calcium, and certain B vitamins. Additionally, studies indicate that regular consumption of fermented dairy products positively influences immunity and reduces the incidence of infections.
• Ginger. It has immunomodulatory effects, meaning it supports the immune system. Its anti-inflammatory properties are comparable to those of non-steroidal anti-inflammatory drugs. Additionally, ginger reduces muscle pain and headaches during infections and also acts as an anti-nausea agent.
• Meat. It is a source of heme iron, which is very well absorbed by the body and plays an important role in the immune system's fight against bacteria and viruses. It can be found in more than just meat. The best plant-based sources of iron include: millet, buckwheat, whole-grain rye bread, legumes (lentils, chickpeas, peas, beans), dried fruits (figs, apricots, raisins), and vegetables such as chard, beets, green peas, spinach, kale, or sprouts, as well as nuts and seeds (especially flax seeds, pumpkin seeds, poppy seeds, sesame, sunflower, and pistachios). It is worth noting that plant-based iron sources should be combined with foods rich in vitamin C, as this increases iron absorption.

Products to avoid

To strengthen the immune system, it is not enough to just add the aforementioned products to your diet, although they are the foundation of strong immunity! To maximize their benefits, highly processed foods—such as fast food, sweets, and salty snacks—should be removed from your diet. It is also important to maintain a healthy body weight, as both excess and deficiency can disrupt the immune response.

Bibliography

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• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3723386/
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