The immune system is a complex set of cells and chemical processes that act to protect our bodies against pathogens—bacteria, viruses, fungi, and abnormal cells. Maintaining and strengthening the immune system throughout the year is essential to ensuring the body's ability to fight and prevent ^disease , and it all starts with simple, familiar choices: choosing nutritious food, getting ^enough sleep, and exercising.

In addition to these good practices, nutritional reinforcement through supplementation of vitamins, minerals and certain compounds can enhance a better immune response.

Which micronutrients help strengthen and reinforce the immune system?

When we talk about immunity, there are some essential vitamins to strengthen the immune system.

Vitamin C

Vitamin C is a water-soluble vitamin that humans cannot produce internally, so it must be obtained through dietary intake, particularly from fruits and vegetables, and/or through supplementation. It may be effective in reducing the duration of a ^cold . As a powerful antioxidant, it may be able to reduce oxidative and inflammatory biomarkers and, therefore, has shown promise in the prevention of certain ^diseases . Supplementation may help prevent and treat respiratory infections ^.

Vitamin D

Fat-soluble vitamin D is a key regulator of the immune response, contributing to the prevention of infections ⁽⁶⁾ (and therefore especially important during the colder months). Although Portugal is a country with sunny weather, which is the main source of vitamin D, 66% of Portuguese adults are deficient or insufficient in this vitamin, ⁷ and supplementation is a possible answer.

Zinc

Zinc, in turn, is a mineral commonly found in immune-boosting supplements. It is crucial for the development and function of all immune cells ^, strengthening our protective barriers. A significant number of respiratory diseases are attributed to zinc deficiency, and zinc supplements have been shown to reduce the duration of respiratory tract infections and ^colds .

Selenium

With antioxidant action, selenium is also a mineral that plays an important role in regulating inflammation and immunity. ¹⁰ Selenium deficiency can lead to increased susceptibility to infections, chronic inflammatory diseases, and possibly cancer. ¹¹ Selenium supplements are also a good way to modulate our immunity ^.

Echinacea

Echinacea is one of the plants with recognized beneficial effects on immunity, with an antioxidant effect and which helps prevent infections ¹² .

Astaxanthin

Astaxanthin is an antioxidant with the ability to decrease oxidative stress and inflammation and improve the immune response ¹³ .

Quercertina

Quercertin is a polyphenol, present in fruits and vegetables, with the potential to improve mental and physical performance and reduce the risk of infections ¹⁴ .

Gut health

Gut health has a direct impact on immune function. Probiotic bacteria have important immunomodulatory and health-promoting properties. Therefore, the use of probiotic supplements may represent a promising approach to improving immune system activity ^.

How to choose a dietary supplement?

Supplements contain vitamins, minerals, or other compounds and are a convenient way to obtain micronutrients in recommended doses, always as a complement to a healthy diet. Although they serve to strengthen our immunity and bring obvious benefits, some precautions must be taken before starting supplementation, as there is no universal prescription. Human beings are very diverse, and can have nutritional deficiencies or excess nutrients, and certain groups require special attention: the elderly, pregnant women, those on restrictive diets such as vegetarians and vegans, and individuals with certain pathologies. To know what is best for our bodies, it is essential to consult a healthcare professional who can recommend appropriate supplements that are truly necessary and that do not interfere with other medications or health conditions. Supplementation should be scientifically informed, with the appropriate composition, dose, and duration.