It is a well-known fact that poor nutritional status carries a higher risk of infection. To keep the immune system protected, it is essential to ensure that nutrition is harmonious, adequate, high-quality, and sufficient in quantity—these are the four laws of nutrition. Vitamins and minerals play an important role in various metabolic processes and are considered essential for the integrity and proper functioning of the immune system. Some of these include: vitamin A and beta-carotenes, folic acid, vitamin B6, vitamin B12, vitamin C, vitamin E, vitamin D, iron, zinc, copper, and selenium. As Boozari and Hosseinzadeh suggest, consuming herbal substances prepared from Echinacea spp., Zingiber officinale, Camellia sinensis, Hypericum perforatum, Allium sativum, Glycyrrhiza glabra, and Nigella sativa can significantly enhance the immune response in the fight against the novel coronavirus COVID-19. These natural products are popularly known as echinacea, ginger, black or green tea, St. John's wort, garlic, and black cumin, respectively.
There are also other food components that provide numerous benefits to the immune system, such as honey, curcumin, quercetin, propolis, and ginseng. Additionally, we have the beneficial effects of prebiotics (fiber-rich foods) and probiotics (yogurt, sauerkraut, kimchi, miso, apple cider vinegar, and kombucha, among others), both of which are crucial for maintaining gut health and modulating the immune response. Probiotics improve immune response, enhance nutrient absorption, and help prevent infections. They can also reduce inflammation and improve intestinal diseases.
The big question is: Where can I find these nutrients? First, it’s important to consult healthcare professionals to determine your specific needs. In the meantime, here’s a list of nutrient-rich foods you can include in your diet to boost your defenses:
Vitamin A and Beta-Carotenes: Found in carrots, sweet potatoes, spinach, chard, peppers, mango, melon, pumpkin, and tomatoes.
Vitamin E: Present in nuts and seeds (almonds, hazelnuts, sunflower seeds, pistachios), oils (such as wheat germ and olive oil), leafy greens (spinach, chard), and fruits like kiwi, mango, and avocado, as well as in whole grains and fatty fish.
Vitamin D: Found in fatty fish (salmon, tuna, trout, sardines), fish oils (such as cod liver oil), dairy products (fortified milk and yogurt), and egg yolks. It is also present in fortified cereals and UV-exposed mushrooms.
Folic Acid: Abundant in leafy greens like spinach, chard, and lettuce, and in broccoli. Also found in legumes: lentils, chickpeas, and beans, as well as in fruits like oranges, bananas, strawberries, and papayas, and in nuts and seeds such as walnuts, almonds, and sunflower seeds. Whole grains, like brown rice and oats, and other animal-based foods like eggs and liver, are excellent sources.
Vitamin B6: Found in animal products like chicken, turkey, fish (salmon, tuna, trout), and dairy products, as well as in legumes, nuts, whole grains, and some fruits and vegetables, such as bananas, spinach, and avocado.
Vitamin B12: Primarily present in animal products such as liver, beef, lamb, fish (salmon, tuna, trout), and dairy products (milk, yogurt, cheese). It is also found in eggs and some fortified foods, though intake should be evaluated in vegan and vegetarian diets.
Vitamin C: Found in fruits and vegetables such as oranges, kiwi, strawberries, papaya, mango, pineapple, and other citrus fruits. Also present in vegetables like peppers, broccoli, kale, cauliflower, spinach, and tomatoes, as well as in herbs like parsley and cilantro.
Iron: Abundant in red meats, liver, chicken, and fish, as well as in legumes (lentils, chickpeas, beans), nuts and seeds, and vegetables like spinach and broccoli.
Zinc: Present in meats (beef, pork, lamb, chicken), seafood (oysters, crab, salmon), legumes, nuts, seeds, whole grains, and dairy products.
Copper: Found in seafood, liver, lamb, nuts and seeds, legumes, whole grains, and vegetables like spinach and mushrooms.
Selenium: Abundant in Brazil nuts, sunflower seeds, fish, seafood, meats, eggs, and some cereals and dairy products.
Ensuring a varied diet that includes all food groups, daily physical activity, and adequate sun exposure are factors that contribute to maintaining a strong and healthy immune system.
Gasmi, A.; Shanaida, M.; Oleshchuk, O.; Semenova, Y.; Mujawdiya, P.K.; Ivankiv, Y.; Pokryshko, O.; Noor, S.; Piscopo, S.; Adamiv, S.; et al. Natural Ingredients to Improve Immunity. Pharmaceuticals 2023, 16, 528. https://doi.org/10.3390/ph16040528
Nova, E., Montero, A., Gómez, S., & Marcos, A. La estrecha relación entre la nutrición y el sistema inmunitario.
