10 Immune Boosting Foods

We all want to optimise our health as much as possible, and we can feel a little betrayed by our bodies when we get sick. Of course, sleep and appropriate exercise are also key in supporting our bodies. However, there are immune boosting foods that can be key in our health.

The short answer is yes.

First let’s take a look at what the immune system is, how it works and then our top foods to support it!

What is the immune system?

The purpose of the immune system is to defend itself and keep things like bacteria, viruses, and fungi out of the body and then destroy any if they happen to get in.

To do this, it has three lines of defence.  We can think of it like our own army!  

Lines of defence

The innate immune system provides the first line of defence; broadly divided into physical/chemical barriers. The physical barriers include the skin and the lining of the digestive and respiratory tract. You can think of the body like a sausage; the skin, keeps everything in, but also things out.  So, keeping our skin healthy is a great way of making sure those pesky bugs don’t get inside!  

Chemical barriers include tears and saliva along with gastric acid.  But also, the microbiome – which is the community of microbes found in the mouth, lungs, gut, and on the skin.  

We then have the innate immune system – which is for want of a better phrase a row of white blood cells (and other participants) that engulf and destroy invaders.  

The third defence is acquired or adaptive immunity – this is the memory bank.  The cells involved in this response help the body remember antigens that it has encountered before – so it can mount a quicker response before the harmful pathogen causes any damage.  This is the basic premise of a vaccine. When you introduce an antigen to the body, it mounts a response so when it is exposed to it in the real world, the body knows how to deal with it.  

The immune system is trained to recognise its own cells as self and leave them to do their jobs.  It is trained to recognise anything that isn’t self and attack it.  

When it works, it works brilliantly and, well, we survive.  

But as you have largely noticed, the immune system is coordinated; it has a number of different forms of defence and therefore a number of different cells.  These cells need certain things to do their job and we can get these things, in many cases, from our diets. 

Immune boosting foods

 

1. Peppers

Red bell peppers contain almost three times the amount of Vitamin C that an Orange does! We all know that oranges are touted for their immune-supporting functions, so these are great additions to the diet too. However, why not increase intake further by looking for foods which contain even more!  

Vitamin C contributes to immune defence by supporting various cellular functions of both the innate and adaptive immune system. It helps encourage the production of white blood cells known as lymphocytes and phagocytes, which help protect the body against infection.  

Vitamin C is a water-soluble vitamin meaning that any excess is simply excreted out. Dietary intake rarely results in toxicity, and if you are supplementing, you are looking for bowel tolerance. 

2. Spinach

Another food rich in Vitamin C, spinach is also packed full of antioxidants like beta carotene. Not that you would know it because the chlorophyll hides the yellow-orange pigment. Beta carotene is converted to Vitamin A in the body but beta carotene, like all carotenoids is an antioxidant. This protects the body from free radicals.  Free radicals are produced by macrophages whilst fighting off invading germs. It’s these free radicals that can then damage healthy cells leading to inflammation. So a diet rich in antioxidants could help mitigate the damage!

3. Shellfish

Many types of shellfish are packed full of zinc and this is a particular powerhouse when it comes to immune function.  It has antioxidant effects protecting against reactive oxygen species and also plays a role in skin health – which as we know is our first line of defence.  In the adaptive immune response, zinc helps immune cells figure out the role they are going to play in fighting off invading bugs too. Shellfish includes both crustaceans like shrimp, crab, or lobster and molluscs like clams, mussels, oysters, and scallops.  

4. Mushrooms

Mushrooms contain the mineral selenium, which plays a role in antibody production.  Selenium also protects against free radical damage too!  Which as we know, free radicals are like the exhaust fumes of our body’s work and this includes when it is working to fight off invading bugs!

5. Leafy Greens

Leafy green vegetables are known for their B vitamin content.  B vitamins are called upon when we are converting what we eat to energy and as we know, when we are busy fighting off invading viruses, our energy levels drop!  This is because it takes a literal army to fight it off and this army needs supplies!  The more we ask the body to do, the more supplies it needs, so fill up on those leafy greens like kale, spinach, collard greens, rocket, watercress, beet tops and cabbage!

6. Red Meat

Red meat is a great source of iron.  Iron comes in two forms, haem which comes from meat sources, and non-haem found in plant sources.

Iron helps destroy bacteria by neutrophils and it also helps immune cells released from the bone marrow become specialised immune cells.

Haem is more easily absorbed than non-haem sources, as plant products often contain phytic acid which binds to minerals (not just iron), inhibiting its absorption. 

7. Turmeric

The inclusion of turmeric in the diet has been seen to increase antibodies to particular antigens and overall, it is seen to improve both innate and adaptive immune function.  Not only that, but it also plays a role in the inflammatory response – making sure it doesn’t get out of hand.  

When we are sick, the inflammatory response is normal – it just needs to occur in the right amount, and for the right period of time.  

8. Broccoli

Broccoli is packed full of vitamins and minerals.  You will find vitamins A, C and E, fibre and antioxidants in these little green trees!  

Vitamin A helps maintain skin health, and also the lining in our respiratory tract.  It is also important for the functioning of natural killer cells, macrophages, and neutrophils.  In the adaptive immune response, vitamin A is necessary for the generation of antibody responses to an antigen.

9. Garlic

Garlic contains sulphur-containing compounds like allicin.  It has been used for centuries to help fight off infections.  Not only that, but garlic functions as a prebiotic which can support the development of a healthy microbiome in the gut – and as we know, the gut is home to around 70% of your immune system! 

10. Ginger

Many test-tube and animal studies suggest that ginger can enhance immune response. What’s more, ginger has powerful antiviral and antibacterial properties.  Ginger is also seen to reduce stress, and as we know, when we are stressed, our ability to fight off viruses and infections becomes compromised.  The stress response in the body is like a redirection of resources, and if we liken it to our ancestors – we could have fought that cold off when we were no longer being chased by a bear!

So, along with opting for immune boosting foods, we also need to manage our stress levels and ensure we are getting adequate sleep, along with appropriate exercise if we are to optimise our health.