Almost all nutrients in the diet play a crucial role in maintaining an optimal immune response and our defense system needs certain factors to stay strong and be able to fight pathogens. Among the most important ones are zinc and selenium.
Zinc is well-known for helping to cut the length of a common cold, but how else can it support our immune system?
There are a number of ways zinc supports the immune system but primarily it activates enzymes that break down proteins in viruses and bacteria so they are less able to spread. Zinc also increases the activation of cells responsible for fighting infection.
The ability of zinc to boost immune system function in certain disorders has been backed up by numerous studies over the past few decades and since we have no specialised zinc storage system in our body, we need to make sure that we get it from our food every day.
5 Plant based foods that are good sources of Zinc are:
1. Legumes - Lentils, beans, and chickpeas are all high in zinc. Half a cup of chickpeas has 1.3 mg of zinc, and a half a cup of kidney beans has 0.9 mg. Note that they do contain phytates, which can affect the absorption of zinc. Cooking, sprouting, or fermenting legumes can help reduce phytates, making it easier for your body to absorb the mineral.
2. Nuts - Nuts can provide varying amount of Zinc. One ounce serving of cashews has 1.6 mg while the same amount of dry roasted almonds has 0.9 mg.
3. Seeds - Seeds are excellent source of zinc. One ounce of pumpkin seeds contains 2.2 mg. Sesame seeds have 0.6 mg per tbsp, and a 3tbsp serving of hemp seeds has almost 3 mg.
4. Oats - Half a cup of oats provides 1.5 mg of zinc. Like legumes, oats (and other whole grains) contain phytates, which can affect how well your body absorbs the mineral.
5. Tofu - Made from soybeans, tofu is an excellent source of zinc. A 4 ounce serving has 1.8 mg of zinc. Since it absorbs flavours well, many vegans and vegetarians use tofu to replace meat in various types of recipes.
Zinc in a few lines can either support the function of the immune system when needed or help control its effects when it starts to attack the body’s own cells. This is why it is considered by many as an ‘immune modulator/regulator’.
Selenium is made of proteins (selenoproteins), that play a major role in reproduction, thyroid hormone metabolism, DNA formation and repair, oxidative damage and fighting of body infections. Dietary selenium has been found to play a role in the immune treatment of viral and bacterial infections. Selenium acts as an antioxidant in the extracellular space, the cell cytosol, in association with cell membranes and specifically in the gastrointestinal tract, all with the potential to influence immune processes. Selenium influences both the innate, 'non-adaptive' and the acquired, 'adaptive' immune systems.
Selenium-rich plant based foods are:
1. Mushrooms - Mushrooms are fungi that contain about 12 mcg of selenium in a 100-gram serving.
2. Brazil nuts - Brazil nuts are one of the best sources of selenium. One ounce, or about six to eight nuts, contains about 544 mcg.
3. Chia seeds - All seeds contain selenium, but some provide more of the mineral than others. Among the different edible seeds, chia seeds offer one of the highest amounts (Per ounce (28-gram) serving, chia seeds supply 28% of the recommended selenium daily value).
4. Cashews - Dry roasted cashews offer 3 mcg per ounce. That may not seem like much, but every bit helps, especially if you follow a vegan diet.
Low selenium levels not only increase the risk of infections, but also contribute to the emergence of new and more virulent flu strains.
As with most things in your body, a healthy diet is key to a strong immune system. This means making sure you eat plenty of healthy foods, exercise regularly, get enough sleep and try to minimise stress. There's no one size fits all and it's best to keep in mind that listening to your body and its needs is the best way to go.