**Optimal immunity depends on optimal nutrition.**

The last two years have put added pressure on our immune system. The Covid virus itself as well as being in lockdown with often minimal time to be in the sun and other complications such as stress and limited access to nutrient-dense foods or perhaps lack of motivation to focus on a nutrient-dense lifestyle.

As a Nutritionist, one of the questions that we always ask is about your immune system.

“How often do you get a cold?”

“How long does it last?”

“Do you suffer from allergies?”.

This gives us a good indication of how well your body can protect against harmful substances, germs, and internal cell changes as well as the ability to produce antibodies (proteins made by the body) to defend and protect against disease.

The reason why a nutritionist thinks this is important to know is that, of all the body’s systems, the immune system responds most sensitively to even the most subtle changes in nutritional status.

Nutrients we need for an optimal immune system

Protein

to make the much-needed antibodies.

Vitamin C

is an antioxidant that has many functions involved with the immune system, including encouraging the production of white blood cells, stimulating the production of antibodies, and regenerating Vitamin E (another antioxidant required for optimal blood vessel’s function and infection-fighting T-cell production).

Vitamin D

enhances the immune system’s response to both bacterial and viral invaders by enhancing white blood cell function.

Zinc

is needed for normal development and optimal function of immune cells and antibody formation. Zinc deficiency rapidly diminishes immune response, giving opportunistic invaders space and time to take hold.

Selenium

is an antioxidant and is also required to produce T and B cell. T cells can wipe out infected or damaged cells, they also help B cells to eliminate invading pathogens. B cells create antibodies. Because of this, selenium depletion occurs when there is an infection and during times of inflammation.

Iron

is vital for the production of all cells throughout the body, including those of the immune system, with deficiencies impacting the production of white blood cells and therefore antibodies to protect against disease.

Food Sources

Vitamin C

Blackcurrants, green and red capsicum, chili’s, oranges, strawberries. With a smaller amount in watermelon, citrus fruits, mango, cabbage, broccoli, and tomato. Vitamin C is destroyed with high heat, although weirdly enough blanching them (ie, broccoli) preserves it.

Selenium
The amount of selenium in a food depends on the soil quality where it is grown. The best sources are organic Brazil nuts, from Brazil (where soil quality seems to be better), wheatgerm, brewers’ yeast, meats, seafood garlic, and organ meats.

Zinc

Meat, liver, eggs, seafood (especially oysters) are the best sources. It can also be found in miso, tofu, brewers’ yeast, mushrooms, and green beans. Seeds, nuts, legumes, and whole grains also contain zinc, but for optimal absorption, it is best to sprout these to help break down the phytates which impair absorption.

Iron

There are two types of iron. Haem and non-haem iron.

Haem iron is in general, more bioavailable and is found in animal sources. Liver, red meat, poultry, fish, oysters, shellfish, kidney.

Non-haem is in plant products. Egg yolk, nuts, legumes, fruit, dried fruit, dried herbs, dark molasses, beetroot, grains, and tofu. Dairy is a pretty poor source of iron.

Vitamin C enhances the absorption of iron, so it’s a good idea to squeeze some lemon juice over your meats before eating them.