How Stress Wreaks Havoc On Your Microbiome

Stress is one of those triggers – like diet or antibiotics – that can throw our gut bugs (our microbiome) badly out of balance.

We know from recent scientific studies that the gut-brain connection is a much deeper one than we could ever have imagined, and the connection goes both ways.

Studies on both mice and humans show that the more diverse our microbiome is, the more resilient we are to stress.

Can this really be true? If so, how can we work it to our advantage?

If we’re severely stressed, our microbiome takes a hit (more on this below). But it also works in reverse: when our microbiome is thrown out balance by something or a combination of things, WE take a hit. How? We become less robust and more stressed.

This is some pretty crazy sh*t! It shows a deeply connected, truly symbiotic relationship between us and those little bacteria. They look after us, and we need to look after them too.

For a look at the host of reasons your microbiome may be out of balance, check out Why Your Gut is Broken

You’ve probably spotted that this also sets up the possibility of a bad feedback loop: we get stressed and our microbiome suffers, then we feel the stress even more, and so on.

We can break that loop by boosting our friendly gut bugs with probiotics and by getting our diet right.

Stress upsets our good bacteria

At any given time we have a balance of good and bad microbes living in and on us. It’s kind of icky when you stop and think about it but there’s a huge ecosystem of trillions of them.

These bacteria are not just hanging around. They are literally wired into our immune system, metabolism and central nervous system helping us humans to function properly. By the way they’re doing the same in every other animal on the planet too!

Given how closely interconnected we are, it’s not surprising that when we’re chronically stressed it can affect our gut bugs too.

Studies with mice have shown that stress increases the amount of bad bacteria in the gut, throwing the ecosystem out of balance. Mice are considered to be sufficiently similar to humans for these studies to give us strong clues of what’s going on in own bodies.

There have also been human studies. So far these have focused on short, acute stress rather than the chronic stress that most of us have (thank you modern life!)

So for example, we know that after a stroke our microbiome changes for the worse. It becomes less diverse with unfriendly species gaining ground.

It’s also known that people who suffer from Post Traumatic Stress Disorder (PTSD) have lower levels of three particular bacteria. However it’s not yet clear if lower levels of those bacteria make us more susceptible to PTSD or follow from having PTSD.

stress inflammation

Lost Nutrients

Anything that upsets our gut bugs, such as stress in this case, leads sooner or later, to our digestion malfunctioning. This leads to absorbing less nutrients from the food we eat. These nutrients are the vital building blocks that enable our body to function and heal.

Without enough of the right nutrients our body is weaker. We find it harder to get and stay well. We catch more coughs and colds and may end up taking more antibiotics.

Taking antibiotics is necessary sometimes but it always damages our microbiome and therefore weakens our immune system. This can lead to a cycle of more antibiotic use, more damage to the microbiome, lowered immunity and yet more antibiotics

Brain On Fire

A scientific review in 2016 found that our microbiome plays a huge role in how our body responds to stress and in particular our brain.

They described our microbiome as the ‘regulator’ that determines the level of inflammation in our brain (‘neuroinflammation’). For a quick intro to the subject of inflammation check out Inflammation: Putting Out The Fire

This also fits with what we know about our friendly bacteria helping our immune system to find the correct level of response to threats, like turning a thermostat up and down. More details here: Supercharge Your Body to Crush Autoimmune Conditions

In this scientific review the authors talk about ‘microglia’. These are immune cells in our brain and central nervous system, a bit like little soldiers defending our brain and nerve cells from attack by pathogens.

The authors say: ‘diverse gastrointestinal microbiota is essential for the continuous preservation of healthy microglia and proper brain function throughout our lifespans’

In other words if we want our brain to function properly throughout our entire life (yes please!!) we MUST have a rich and healthy microbiome

Get By With a Little Help From Our Friends

One thing that’s clear from both mouse and human studies is that our friendly bacteria help us cope with stress.

In one study, for example, levels of the stress hormone cortisol were significantly lower in people taking probiotics as compared to those taking a placebo. This had the effect of boosting the subjects resilience to stress and improved their emotional responses.

In other words boosting our microbiome will help us to feel positive in the face of stress, as opposed to feeling bummed out and hopeless, overwhelmed by a torrent of negative thoughts.

Soothing Strategies

When we take a step back to look at the bigger picture, there’s no question that chronic stress can damage our microbiome. However there’s more to it than that, as we now know that our microbiome also plays a big role in PROTECTING us against stress.

Armed with this knowledge we can engineer ourselves to be more resilient to life’s stresses and strains by taking care of our old friends, the bacteria.

It can be act of daily self-care, for example by eating a little live, cultured food with every meal and by avoiding processed food altogether. Check out Clean Eating: More Than Just An Elitist Fad

I also suggest some gut-friendly coping strategies here: 7 Stress Busting, Gut Soothing Strategies


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26 thoughts on “How Stress Wreaks Havoc On Your Microbiome”

  1. Well these days stress is quite killing me but my life saver is music. I take no meds but listening to good calming music helps me think better.

  2. I agree with this. Back when I used to be super obsessed with work that sometimes I tend to skip meals, eat whatever that’s easy to chew and just bury myself in my workload. I’ve gotten sick a few times (ulcer). It was a disaster!

  3. If you’re constantly under stress, you can have physical symptoms, such as headaches, an upset stomach, high blood pressure, chest pain, and problems with sex and sleep. Stress can also lead to emotional problems, depression, panic attacks, or other forms of anxiety and worry.

  4. I think a lot of people have been under stress for so long that they don’t even realize how much it’s affecting their body. It’s good to know that there are things we can do to improve our health.

  5. Amazing! I learned something new about how stress affects my microbiomes from your post. Thanks for sharing! 🙂

  6. Stress has a lot of negative effects in our physical and mental health. Thank you so much for the tips on how we can avoid this!

  7. blair villanueva

    I hate stress. It’s either it makes me not to eat, or eat so much! And gives me a headache. To combat stress, I stop overthinking, grab a warm bubble bath, and sleep early. Next day I’m back my mojo!

  8. Thanks so much for this imformative practical post!! I so agree with every single word! I am just learning about gut health and the microbiome and am blown away with the awesomeness of it all!!! I will be looking forward to more posts!

  9. Thanks for sharing this, it is really interesting. I feel as if I am constantly stressed, so I believe I need to try to get some extra probiotics in my daily routine.

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