Does Summer Heat Affect Your Gut Health? What We Know So Far

- You do all the right things to care for your gut microbiome, but there’s another factor worth considering — the summer heat.
- Animal studies and cell cultures show heat can affect gut permeability. In humans, this may allow bacteria to enter your bloodstream.
- Get the details on the science, then find out how to support good gut health all summer long (even with a heat wave).
You know that taking care of your gut microbiome includes eating well, staying hydrated and managing stress. But what about staying cool? Extended heat exposure may affect gut health, according to early studies. Here’s what we know so far, plus tips to help your gut thrive — even in the middle of summer.
What’s the connection between heat and gut bacteria?
Animal studies have found that hot temperatures may increase permeability of the gut lining, allowing bacteria to pass into the blood.[1][2] Animal studies don’t necessarily predict human results, but the findings can help paint a larger picture.
A cell culture study of human epithelial cells (the cells that line your internal organs) found that heat exposure may increase intestinal permeability.[3] In humans, increased intestinal permeability (aka leaky gut) allows toxins to pass through the stomach lining.
Good news: You evolved to adapt to hot temperatures. A process called heat acclimation naturally helps maintain your core temperature so your body stays balanced. In response to high heat, your body releases heat shock proteins (HSPs), which have protective properties in your cells. Early research has found that HSPs may play a role in maintaining gut permeability and protecting your intestinal cells.[4] [5]
Tons of different factors can affect gut health, from your diet to your sleep schedule. There’s a growing body of evidence that heat is another factor to consider. [6]
How to help your gut bacteria this summer
All this might sound like bad news, especially if you live in a place with magma-hot summers and no AC. But there are things you can do to help your gut bacteria cope with the summer heat.
Take prebiotics
There’s no drawback to feeding your gut any time of the year. To help keep your gut balanced when temperatures spike, give it the nourishing power of prebiotics to feed good gut bacteria.
Related: Why Prebiotics Are More Important Than Probiotics for Your Gut
Drink more water
When it’s hot, you know you should be guzzling water, but you may not know why your body needs extra hydration. Water hydrates the mucous membranes that line your entire digestive tract. These membranes allow nutrients to travel to the right place and block toxins, viruses and bacteria from entering your bloodstream.[7]
When you don’t get enough H2O, you face everything from constipation to a suppressed immune system. To protect against this, the CDC recommendations for staying hydrated in summer are to drink about ¾ to 1 quart of water per hour all throughout the day — not just when you’re in the sun.
Get quality sleep
With hot nights and bright early mornings, it can be hard to get to sleep and stay asleep in the summer. Aim to turn your bedroom into a dark, cool cave to sleep in — or take a shower before bed and get some blackout curtains because losing sleep can wreck your gut.
Read next: Signs Your Gut Is Unhealthy and Why You Should Fix It
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