Certain changes to your routine, such as eating a gut-friendly diet and exercising regularly, not only improve your gut health but strengthen your immune system at the same time.
The immune system is a network of tissues, organs and cells distributed throughout the body to protect against disease.
Around 70–80% of your immune cells exist in your gut. The microbes that live in your gut – collectively called your gut microbiome – are constantly interacting with these immune cells. In fact, they serve as trainers, educating these cells about the difference between harmful and harmless things.
Your gut microbes produce beneficial compounds, such as short-chain fatty acids, when they ferment fibre. Certain microbes can also make useful nutrients, such as B vitamins and vitamin K. These are important for a healthy immune system.
Interactions between your gut microbiome and your gut’s immune cells can have far-reaching immune effects beyond your gut. So, habits that are good for your gut tend to support your immune system as well.
But which lifestyle adjustments can help improve your gut and immune health? Let’s take a look at seven strategies to keep your gut happy and bolster your body’s defenses.
1. Eat a gut-friendly diet
The quality of your diet affects how well your immune system works. Getting the right amounts of certain nutrients can help keep your immune system firing on all cylinders.
The best way to get all the nutrients you need is to eat a well-balanced diet that’s filled with lots of different plant foods. These include fruits, vegetables, nuts, seeds, legumes, whole grains, herbs and spices.
Not only will a wide variety of plants provide lots of valuable vitamins and minerals, they offer heaps of fibre and plant chemicals, such as polyphenols.
Fibre is crucial to good gut health. Some types help with healthy digestion and pooing, while others feed your gut microbiome.
Most of us aren’t eating enough fibre. We should aim to get 30 grams a day, so increasing your intake can be one way to make your diet healthier in an especially gut-friendly way.
What you can do:
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Add, don’t take away. Rather than making drastic changes, add in new plant foods gradually. This can be an easier way to make your diet more gut-friendly. Try replacing half a portion of meat with lentils or beans, or sprinkle some seeds on top of a dish.
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Include many colours in each meal. This is known as ‘eating the rainbow’ and it offers you a range of polyphenols. Your gut bacteria love these plant chemicals, which also have antioxidant and anti-inflammatory properties.
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Try fermented foods. These may support your gut microbiome, so give natural or Greek-style yoghurt, sauerkraut or kombucha a try. It’s important to pick products that contain live bacteria.
2. Get enough sleep
You may have noticed that you’re more susceptible to sniffles after a busy period when you’ve not gotten enough sleep. This is because sleep deprivation lowers our defenses against certain illnesses.
But did you know that getting enough shut-eye is also important for your gut? Evidence suggests that quality sleep is associated with a more diverse gut microbiome, and scientists believe that a diverse range of ‘good’ bacteria in your gut is a sign of a healthy microbiome.
Experts recommend that adults get at least 7 hours of sleep each night. So, if you tend to get less, taking steps to stay asleep longer could help your gut and immune system.
What you can do:
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Develop a regular bedtime routine. Going to bed and getting up at the same times throughout the week can improve the quality of your sleep. It’s also good to have a consistent routine that involves winding down before bed.
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Create a good sleep environment. You’ll give yourself the best chances of a good night’s sleep by making sure your bedroom is quiet, cool and dark. Keep it ventilated if you can, and store electronic devices somewhere else.
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If you can’t sleep, get out of bed. Lying in bed worrying about not sleeping rarely leads to slumber. Instead, get out of bed and do a relaxing activity, such as reading a book. There’ll be less of an association between your bed and struggling to fall asleep, and the activity may help you feel more sleepy.
3. Exercise regularly
Regular exercise isn’t just good for maintaining strength and fitness; it keeps your immune system fit, too.
Exercise is also great for stress relief, which is important, as the presence of stress can reduce how well your immune system and gut work.
When it comes to your gut, moving your body also helps move your bowels, reducing the risk of constipation. There’s also evidence that exercise can have a positive effect on the diversity of bacteria living in your gut.
What you can do:
The NHS recommends that adults aim for the following amounts of physical activity:
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strength training that works all your main muscle groups twice a week
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at least 150 minutes of moderate-intensity exercise or 75 minutes of vigorous exercise each week
Moderate exercises include walking briskly, cycling or pushing a lawnmower. Vigorous exercises include running, swimming or walking up stairs.
4. Get enough vitamin D
Vitamin D is vital for regulating the nutrients that support your bones and muscles. But the benefits don’t end there.
This vitamin also plays a role in both your immune system and your gut health. It helps secure the lining of your gut, and it can encourage the production of certain amino acids there that defend against harmful microbes.
Our bodies make a lot of the vitamin D we need from sunlight, giving it the nickname ‘the sunshine vitamin’.
Unfortunately, those of us in the UK are unlikely to get enough sunlight to make all the vitamin D we need from autumn through spring. And as it’s difficult to get vitamin D from food, experts recommend that we consider a supplement until the sunnier months.
What you can do:
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Get outside. Your body needs direct sunlight on your skin to create vitamin D. Try to spend 15–20 minutes in the sun each day during the spring and summer.
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Take a vitamin D supplement (10 microgram/day) during autumn and winter. Between October and early March, the UK doesn’t get enough sunlight to support our vitamin D needs.
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Eat foods containing vitamin D. Although it’s tricky to get much vitamin D from your diet, oily fish, red meat, egg yolks and some mushrooms are decent sources. You may also find it added to some breakfast cereals, plant-based milks and other products.
5. Limit the amount of alcohol you drink
Alcohol can have a negative effect on both your gut health and immune system. So, if you’re looking out for both, you may want to limit your number of drinks.
UK guidelines recommend that if you drink alcohol, you should have no more than 14 units per week. A typical-strength, medium (175-millilitre) glass of wine is around 2.3 units.
When you drink alcohol, it makes its way into your bloodstream via your gut. Once it’s there, it can weaken the lining of the gut, alter the balance of your gut microbiome and interfere with immune cell communication.
What you can do:
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Try non-alcoholic options. Most shops and pubs offer a decent range of non-alcoholic and low-alcohol versions nowadays, along with alternatives such as low-sugar kombucha and soda or sparkling water.
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Set a goal. If you’re planning to cut back, giving yourself a target can make it easier.
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Seek support. If you need some help, you can find plenty of information and resources on the Drinkaware website.
6. Quit smoking
Giving up smoking will improve all areas of your health.
With our topic in mind, smoking has a negative impact on how effectively your immune system works.
After you quit, it takes some time for certain parts of your immune system to bounce back. However, your first line of defence against disease returns to normal quickly.
When it comes to your gut, smoking can disrupt the balance of your microbiome, encouraging the growth of ‘bad’ bacteria. It can also increase your risk of gut-related disease, such as acid reflux and stomach cancer.
What you can do:
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Look at the available support options. Giving up smoking can be very difficult. Thankfully, there are many resources to help, from advice and apps to medications and support groups. Check out the NHS’s support page for more information.
7. Consider probiotic supplements
Probiotics supplements contain live bacteria that can benefit your health if you take the right amounts. These supplements come in sachets, capsules or liquids.
Plenty of evidence indicates that probiotics can support your gut health by helping to manage gut symptoms.
Research suggests that the bacteria in your gut help teach your immune system to target harmful bacteria while leaving ‘good’ bacteria alone.
As we’ve mentioned, most of your immune cells are in your gut. So, the healthier their environment is, the better they’ll be at protecting your body.
What you can do:
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Have a trial period. Probiotics can have different effects from person to person. If you’re thinking of trying one, plan a trial period of around 4–12 weeks to see if you notice any differences.
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Discuss with a doctor. If you’re interested in probiotic supplements but are currently taking medication, speak with your doctor to make sure that the supplement will be OK to use.
Worst foods for your gut health
Your diet is key to your gut health. While some foods are great at supporting your gut and its microbiome, others offer very little from a gut health perspective.
Try to limit these foods to support your gut health:
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high-sugar foods, such as sweets, biscuits and fizzy drinks
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high-fat foods, such as fried foods, pastries and processed meats
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high-salt foods, such as crisps, takeaways and ready meals
Too much sugar, fat or salt in your diet can weaken the lining of your gut and have a negative impact on the balance of ‘good’ and ‘bad’ bacteria living there.
It can be good to cut back on ultra-processed foods, too. These are often low in useful nutrients and fibre. They also tend to be high in added sugar, fat and salt, as well as additives like emulsifiers, sweeteners, flavourings and colourings. The gut health effects of these additives aren’t yet clear.
Summary
The health of your gut and the microbes within it play an important role in how well your immune system works.
There are many habits you can develop to support both your gut health and the strength of your immune system. These include:
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eating a gut-friendly diet
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aiming for at least 7 hours of sleep a night
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exercising regularly
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getting enough vitamin D
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limiting how much alcohol you drink
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quitting smoking
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considering probiotics
Due to how closely entwined your gut health and immune system are, any changes you make to support your gut will have the benefit of strengthening your immunity. A happy gut tends to equal a happy immune system.
To learn more about other gut health topics, visit Symprove’s Gut Hub.
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