One of the first things people ask me when I tell them I have a PhD in immunology is “How can I strengthen my immune system?” (closely followed by “Why do I always get colds?” and “How come X never gets sick and I am sick all the time?”.
What people don’t realise is that the answer is rather complicated and, most likely, the person you are asking can tell you a lot about the molecular pathway around an immune response and what proteins are involved/what genes are expressed, and not a lot about how you can stay healthy (eat more vegetables? do more exercise? make sure you have no deficiencies?).
But if that is one of your questions, what I can say to you is that practices like yoga and meditation could be really valuable in helping you to support a healthy immune system.
Mind–body practices influence gene expression
If you know what gene expression is, skip ahead to*
Our DNA contains information, in the form of genes, which need to be switched on and expressed to form functional gene products like proteins. So, for example, when the body detects a foreign invader, it will signal to switch on the expression of genes that code for molecules that drive inflammation (amongst other things), such as pro-inflammatory cytokines. This ensures that we only express genes and create gene products when we need them – you wouldn’t want these pro-inflammatory molecules circulating in your body all the time, would you?
*I came across a recent review article, which consolidated research§ looking at the effects of mind–body practices like yoga, mindfulness meditation and tai chi on gene expression. Overall, it identified 18 studies which show that such practices do indeed cause changes in gene expression.
Mind–body practices counter the effects of stress on the immune system
We all know that stress is bad for us – but did you know it’s bad for your immune system too? Chronic stress can lead to chronic inflammation, where the immune system is constantly active, fighting an invisible enemy. This constant battle can cause damage to healthy tissue and in some instances has been associated with conditions like cancer, heart disease and autoimmune disease like Crohn’s disease.
What the review article highlights is that practices like yoga, mindfulness and tai chi are associated with a reduced expression of genes that code for inflammatory molecules.^ This includes studies looking specifically at gene expression in patients with cancer, IBD and Alzheimer’s. In essence, mind–body practices tell our body that we don’t need to go crazy on the inflammation, there is not invisible enemy to fight.
This is consistent with a growing body of evidence showing benefits for yoga in bringing balance back to the immune system by tackling the stress response (which I’ll save for another time).
But… the usual caveats apply
- The studies were relatively small, in terms of participant numbers
- The studies were variable in terms how what they did, what the intervention was, how long for, what they measured etc
- The long-term effects on immune system function were not clear; how long do you need to practice for, how often, how long the effects will last etc
So, as ever, more research is needed to fully understand how these practices impact our immune system and whether they might be helpful in conditions where inflammation is out of control.
Either way, the next time someone asks me what to do to strengthen their immune system, I think I’ll resist digging into my immunology brain and instead suggest yoga (or mindfulness, or tai chi, or qi gong or probably yoga nidra too) instead.
Stay tuned for more on the impact of yoga on the immune system!
§ Consolidated is a bit of an overstatement. They basically collated all the studies and reported back on each one, with no synthesis. Sorry, frustrated ex-editor rant over…
^Genetics police – yes, I know, I am oversimplifying. It’s a blog post. Chill.