We're sorry, we lied. This post won't talk about individual foods - but it will tell you how to make sure that your diet is supporting a well functioning immune system.
A boosted immune system is not a good thing - it's a marketing term
Hopefully we can convince you that 'how do I boost my immune system' is a bad question.
You can think of your immune system like a group of police dogs. It's job is to sniff out dangers and find things. You want the dogs to be robust, with a good nose for finding things. But you don't want them to be over-hyped, barking, and reacting to every little thing that goes past.
A 'boosted' immune system often means an 'overactive' immune system. This can pave the way to allergies and autoimmune conditions - where the immune system attacks healthy cells that aren't a genuine threat.
Diet and immunity are similar in that more is not better, and it can be worse. 'Sufficient' is best.
It's impossible to know what individual foods do to the immune system- science isn't there yet
Nutrient metabolism (where nutrients go in the body, how they get there, and what they do there) is more complicated than you could possibly imagine. It's hard enough to tease out effects of individual nutrients, let alone foods, which each have a ton of different nutrients and compounds in them (there are literally thousands of potentially bioactive compounds in food, and then there is the rest of your lifestyle to account for too).
Because it's impossible to map all the different interactions, most studies are done either in the lab or in animal models - not humans. Usually, they are looking at individual markers of inflammation, or individual vitamins/ minerals/ compounds.
It is way too simplistic to take any of these individual findings and extrapolate them to draw conclusions about the immune system as a whole, or the diet as a whole.
Remember - the scientists are not the ones making big claims about foods on the immune system - 99% of the time it's journalists looking for studies that can sound like a headline.
But vitamin, mineral, protein, and antioxitant rich diets lead to better health
Even though we don't understand individual foods, we do know from human research that there are certain types of diets that reduce your risks of getting sick. Perhaps disappointingly, it's not very different to the advice you've probably heard a million times.
The typical 'Western' diet (high in added sugar and saturated fats, but low in fruits and vegetables, wholegrains, fibre, and omega 3 fats ) may adversely affect some immune markers, while a plant-rich, colourful diet overall leads to better health.
If you only take one thing away, let it be this: EAT MORE COLOUR.
And you may need more nutrients when you are sick
It is true that some nutrients/ compounds (not foods!) are required for a well functioning immune system.
Immune processes can't happen with enough vitamins A, C, D, and some B vitamins - along with minerals like zinc and selenium and macronutrients like protein and healthy fats. This is why we see poor outcomes in the developing world where there is not enough food.
However, if you live in the developed world, as long as you are eating a balanced (colourful!) diet and getting enough sunshine, you are almost certainly getting more than enough of these nutrients. This is even true for vitamin C - the poster boy for immunity. Where there are benefits to supplementation, it's usually because there is little in the diet.
In fact, sometimes supplementation can be harmful, because there are some nutrients that are stored in the body longer term, and we don't have a good way of getting rid of it when there is too much.
Don't forget about sleep, exercise, and stress management
Exercise, sleep, and managing chronic stress are almost always going to decrease your chances of getting sick.
Further, if you're already sick, the immune system is designed to act on your brain to make you more sleepy. This is partly because when you sleep, your immune system can make sure to remember the infection better, so that next time it's not as bad.
Plus, your immune system keeps you alive, so your body will prioritise giving energy to immune function, over normal sensations of alertness and physical activity. This is because before antibiotics, people would regularly die from infections we might now consider commonplace.
So if your body is telling you to sleep - DON’T FIGHT IT!
If you're getting sick a lot, talk to your GP
Getting sick more than a few times a year is NOT normal. If you find yourself getting sick or feeling tired all the time, it is worth investigating further. Sometimes, dietary deficiencies do happen even in the developed world - the most common ones being iron and vitamin D deficiency. But these deficiencies can have similar symptoms to a lot of other conditions, so it's critical to get things properly checked out!
And if it's all still overwhelming, we're here to help
It's all well and good telling you to eat a colourful diet - but if you're struggling actually implementing this, or you're not sure what a properly balanced diet looks like, send us an email at contact@sciencexartnutrition.com or book a free consultation call.
And if you found this helpful, share this post with someone who still believes in ‘immune-boosting’ foods!"