Vitamins, minerals & the immune system

Whether you're fighting an infection or have a cold, adding some immune-boosting vitamins and minerals to your daily diet can be incredibly beneficial. In fact, certain vitamins, minerals, and supplements have been shown to fine-tune immune function, improve antibody production, and reduce inflammation so you feel like your best SELF.

In this article, we'll cover some of the best immune-boosting vitamins and minerals, and how they can benefit your health, along with some simple suggestions for foods in which you can find them.

Which vitamins are best for a strong immune system?

Many vitamins have been shown to help boost your body's ability to fight off infections. Here are some of the best immune boosting vitamins.

1. Vitamin C

Vitamin C plays a central role in immune function and is often used to support the body's defenses against infection. A 2006 study in the Annals of Nutrition & Metabolism found that getting enough vitamin C in the diet can help reduce the symptoms and shorten the duration of respiratory infections.

Recommended intake per day in Sweden: 75 mg for adults

A medium-sized (125 g) yellow pepper contains a whopping 205 mg of vitamin C!

2. Vitamin D3

Vitamin D is an important micronutrient involved in many aspects of health and is also one of the best immune-boosting vitamins. Not only is vitamin D3 integral to the function of immune cells in the body, but a deficiency in this important micronutrient can actually increase the risk of infection.

There are several forms of vitamin D. Vitamin D3 is the form of vitamin D that forms in our own skin when we stay in the sun and is also found in, for example, fish, meat and eggs, as well as foods enriched with vitamin D3. Vitamin D2 is found in mushrooms, such as porcini mushrooms and chanterelles, as well as foods fortified with vitamin D2. The bioactivity is slightly lower for vitamin D2 than for vitamin D3 .

In order to get enough vitamin D, the Swedish Food Agency recommends that certain groups take dietary supplements with vitamin D. This applies to all children under the age of 2 and all adults over the age of 75. This also applies to anyone who does not eat fish or vitamin D-enriched food and anyone who is not exposed to sunlight in the summer. Pregnant and breastfeeding women are covered by the advice if they belong to one of these groups.

Recommended intake per day in Sweden: 10 micrograms for both sexes between the ages of 2-75 who spend time in the sun, and 20 micrograms for those who spend little or no time in the sun.

A piece of salmon (125 g) contains about 13 micrograms of vitamin D

Did you know that: During the summer months, solar radiation on the skin is the most important source. To form vitamin D corresponding to a daily intake of 5-10 micrograms from food, it is enough in June and July to be outside in linen for up to 15 minutes, 2-3 times a week. The vitamin is stored in the body and what has been formed by the sun can cover part of the need during the winter months.

3. Vitamin A

This fat-soluble vitamin is important for maintaining healthy vision, supporting skin health, and promoting proper growth and development. In addition, vitamin A is also essential for the development of certain immune cells that are necessary to fight inflammation and infection, making vitamin A one of the best vitamins for boosting the immune system.

We get vitamin A in two forms:

• Preformed vitamin A (retinol and retinyl esters) found in animal foods
• Provitamin A in the form of carotenoids which are mainly plant-based and where beta-carotene is the most common carotenoid

Carotenoids can be converted into vitamin A in the body if and when needed. The total content of vitamin A in food (from both animal and vegetable sources) is often expressed as retinol equivalents (RE).

Recommended intake per day in Sweden: 700–900 RE for women and men respectively

A boiled organic egg contains 252 RE

Retinol and related compounds have a vitamin A effect, just like some carotenoids, which are converted to retinol compounds in the body. The total vitamin A effect of the retinol and carotenoid contained in a food is stated as retinol equivalent (RAE). Vitamin A is calculated using the following formula: Vitamin A = retinol + 1/12 * beta-carotene + 1/24 * other carotenoids.

One carrot (100 grams) contains 775 RAE

4. Vitamin E

Vitamin E acts both as a fat-soluble vitamin and as a powerful antioxidant, helping to fight free radicals and prevent oxidative damage to cells. As one of the best immune-boosting vitamins, studies show that foods with vitamin E can improve immune function, increase white blood cell production, and increase resistance to an infection.

Recommended intake per day in Sweden: 8–10 mg for women and men respectively

A handful of sweet almonds, about 16 pieces (20 grams) contains 5 mg of vitamin E

5. Vitamin B6 (pyridoxine)

Promising research suggests that vitamin B6 may help boost the immune system to fight off unknown invaders in the body. According to a study published in the European Journal of Clinical Nutrition, administering vitamin B6 to critically ill patients could significantly improve their immune response over a two-week period.

Meanwhile, other studies show that a lack of this essential vitamin can reduce the production of important antibodies involved in the immune system.

Recommended intake per day in Sweden: 1.2 – 1.6 mg for women and men respectively

A large chicken fillet (200 g) contains 1.8 mg of vitamin B6

Which minerals are best for a strong immune system?

Several minerals have been studied for their impact on immune function and their ability to support the body's natural defense system. Here are some of the best minerals for the immune system.

1. Zinc

Often considered to be one of the most effective immune-enhancing substances, zinc is essential for maintaining health. Research shows that zinc helps regulate the immune response and is necessary for the survival, proliferation and maturation of immune cells.

Clinical studies have also shown that getting enough zinc in your daily diet can reduce the incidence and improve the outcome of serious conditions such as pneumonia and malaria.

Recommended intake per day in Sweden: 7–9 mg for women and men respectively

One tablespoon of pumpkin seeds (10 g) contains 0.85 mg of zinc

2. Iron

Although iron is best known for its role in red blood cell production and oxygen transport, iron is also considered one of the best immune boosters.

Studies show that iron deficiency anemia can impair the body's immune system, potentially increasing the risk of disease and infection. Women, infants, children and those following a vegan or vegetarian diet may be at increased risk of iron deficiency.

Recommended intake per day in Sweden: 9 – 15 mg for women and men respectively

A square of dark 70% chocolate (10 g) contains 1.5 mg of iron!

3. Selenium

Selenium is a powerful micronutrient that acts as an antioxidant to neutralize harmful free radicals and reduce cell damage. In addition to initiating immunity, studies show that selenium may also be involved in regulating an exaggerated immune response to prevent widespread inflammation.

A review in The Lancet also noted that low selenium intake may be associated with several adverse health effects, including poor immune function, cognitive downregulation, and increased risk of mortality.

Recommended intake per day in Sweden: 50 – 60 micrograms for women and men respectively

5 brazil nuts (25 g) contain 56 micrograms of selenium