Worried sick? How stress impacts your immune system

We’re living through a global pandemic, so it’s no wonder stress levels have crept up in most people’s lives. We’ve all found ourselves needing to adjust to sudden changes, accept a “new normal” and face the uncertainty of not knowing how or when the world and our own local “bubble” will change again.

One of the ways stress impacts our body is preventing our immune system from functioning at its best. It’s a vicious cycle, too – when we get sick, stress levels tend to increase, making it harder for our immune system to fight off the problem.

So, it’s good to recognise when you’re feeling stressed and know how to manage stress when it does arise.

Good and bad stress 

Some stress can actually be good for us – stress can help your body conserve energy when it’s hungry, instigates the body’s natural fight-or-flight response when faced with danger and can help the immune system fight injury or infection. However, chronic or prolonged stress can negatively impacting the body’s immune response.

How does stress affect your immune system?

Stress affects your immune system, making you more vulnerable to catching illnesses.

Stress raises your cortisol levels, which can weaken your immune system if they stay high for too long. Stress can also damage your body’s own cells and even trigger responses from your immune system, including elevating inflammation, which can make you more susceptible to viruses and infections.

The COVID-19 pandemic is an example of a particularly stressful life event that can cause what experts call chronic stress. Chronic stress is prolonged, severe stress and can affect the immune system by decreasing the body’s lymphocytes – white blood cells that help fight off infection.

So how do you know if you’re stressed?

Stress appears when things feel unpredictable or out of control. Do you find yourself constantly sleepy? Or irritable in some way? These are signs of stress. Other common signs to watch for include acne, frequent headaches, lack of energy and digestive issues.

Stress also shows up in the form of increased heart rate and tense muscles. This is caused by the brain flooding the body with chemicals and hormones to help you deal with what’s making you stressed or uncomfortable.

4 ways to keep stress in check

Stress is an inevitable part of life, and while there’s no magic bullet, there are lots of things you can do to help keep it in check.

1. Eat a healthy diet
A varied, healthy diet full of micronutrients is essential for maintaining a healthy immune system. Research has shown that better-nourished people are better equipped to have healthy immune systems. Eat foods rich in nutrients like vitamins C and D and zinc which have been singled out as important for immunity. There’s also plenty of plant foods that help mood, anxiety and even depression.

2. Exercise
Getting active can help protect your immune system. Exercise doesn’t need to be intense to help manage stress – moderate intensity exercise will do the trick (think a walk, jog or spin on the bike).

3. Touch
Emotions have a big impact on our bodies, so it makes sense that the more connected and supported we feel, the less stressed we are. While we still need to stay safe and socially distant, if you live with people you can safely give a good hug to then go for it! Science shows hugs can help combat stress.

This is because physical touch:
- stimulates the release of dopamine, a chemical that carries messages between brain cells and is involved with how we experience pleasure, satisfaction and motivation;
- increases serotonin, known as the “happy chemical” a natural mood stabiliser; and
- it also decreases cortisol, which as mentioned can negatively impact the immune system.

If you do live alone, staying in touch with friends or cuddling a pet can help – maybe it is time to get that four-legged friend after all…

4. Sleep
Good sleep has been directly shown to positively affect the immune system. Why? Because quality sleep and keeping our internal body clocks (circadian systems) ticking well, are essential for maintaining peak physical function.

During sleep, the immune system releases proteins (cytokines) which are important for fighting infections and inflammation and also help with our stress response.

While social distancing and spending more time at home may have meant some people have been getting more sleep, for others it might have meant getting much less. Either way, keep prioritising a good night’s sleep in order to give your immune system its best chance of staying fighting fit.