How can probiotics help the immune system?

Gut bacteria and your immune system

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15 November 2017

Friendly bacteria and your gut

Your digestive system depends on a delicate balance of good and bad bacteria. The good bacteria help to digest food properly, balance pH and keep pathogens at bay. This can help to prevent problems like constipation, wind, IBS and bloating.

However, things like poor diet and stress can reduce the numbers of these friendly bacteria, allowing unfriendly bacteria and yeasts like candida to thrive. This can trigger digestive problems and even further problems like thrush. 

To support their friendly gut bacteria, many people choose to take a probiotic to top up the levels of friendly bacteria in their systems. These can come in the form of fermented food, yogurts and supplements. But could these probiotics have more uses than improving digestion? 

How are the gut and the immune system linked?

You might not think your gut and your immune system are linked, but they actually share a very close relationship!

As much as 70-80% of immune cells are located in the gut, so the health of your gut can really impact on the health of your entire immune system. A sluggish, unhappy gut will result in ineffective immune function – that means more colds, flu and other infections!

Inflammation and the immune system are also closely tied, with inflammation acting as a signal to trigger an immune response. So if too much unhealthy food is causing inflammation in the gut, this can cause the immune system to go into overdrive, triggering problems like hayfever and eczema. On the other side of this coin, repeated activation of the immune system can cause it to become unresponsive, allowing infections to take hold more easily. 

In addition, the gut plays a key role in the digestion of food and subsequent absorption of vitamins, minerals and other nutrients – including those that are vital for the immune system! 

How can improving gut flora support the immune system?

The main functions of your friendly gut bacteria are to aid the digestion of food and keep unfriendly bacteria at bay, which are both great news for your immune system. In fact, one study showed that athletes who took a probiotic daily had 40% fewer colds than when they took a placebo1.

So how does your gut flora support your immune system? Firstly, keeping a healthy balance of bacteria in your gut means that food will be more effectively broken down and the nutrients it contains can be better absorbed. This means you can make the most of all the (hopefully) healthy food you’re eating! It doesn’t matter how many oranges you eat – if you can’t digest them properly then you won’t benefit from all that vitamin C

Secondly, friendly bacteria provide a barrier against harmful bacteria that enter your system. We don’t live in a completely sterile environment, so we frequently ingest harmful bacteria, whether from food, germs on our hands or germs on our cutlery, glasses and mugs. However, any pathogens that are ingested tend to be fought off by our friendly bacteria. Not only can they fight these invaders off, but simply by taking up room and using up all the food available to them in your gut, there is effectively no room for unfriendly bacteria to grow. This leaves your immune cells free to fight off infections in other areas of the body like the respiratory system.

A good population of friendly bacteria also helps to keep the digestive system in generally better condition by keeping inflammation under control, balancing pH throughout the digestive tract and helping to ease digestive problems like IBS. This creates a better environment for your immune cells to thrive. 

Natural sources of probiotics

Probiotics can be found in many foods, so it can be beneficial to include these in your diet. Look for fermented foods such as kimchi, sauerkraut, miso soup, apple cider vinegar, pickles and tempeh. Fermented foods make up a large part of the diets of those in many Asian countries, where people have high rates of good health.

In addition, you can look out for yogurts that have live cultures added to them. These can be beneficial, but are not as natural as fermented foods and can be quite sugary.

Probiotic supplements

A great way to ensure you’re getting the friendly bacteria you need is by taking a probiotic supplement. There are so many out there, it can be hard to decide which one is right for you!

One brand that I always recommend is Optibac. They have a fantastic range of well-researched probiotics, each containing different strains that work best for the different scenarios they’re aimed at.

In this case, Optibac’s For Daily Immunity would be the best choice. It contains 2.5 billion live cultures of 4 different types of bacteria, as well as vitamin C, green tea extract, grape seed extract and pine bark extract. Vitamin C is a known immune-supporting vitamin, while green tea, grape seed and pine bark are all rich in polyphenols which are great for the immune system.

I’d also recommend taking Molkosan alongside your probiotic. This is often referred to as a ‘prebiotic’, since it contains l+ lactic acid that helps to create a welcoming environment for friendly bacteria.

A.Vogel Molkosan Original | Contains Concentrated Whey | L+ Lactic Acid | Suitable for Vegetarians

£7.99 (200ml) In Stock

Keep an eye on your diet

If you’re taking a probiotic, it’s also important to take a look at your diet –after all, if you don’t fix whatever has killed off your friendly bacteria, then you may find that the probiotics you’re taking are quickly killed off too!

Improving your diet generally can be a big help – so look at including lots of fresh fruit and vegetables, lean protein, complex carbohydrates and healthy fats. In particular, make sure to reduce your intake of sugar and refined carbohydrates such as white bread as your friendly bacteria don’t like these! Try to avoid to many inflammatory foods like alcohol, dairy and red meat as well. 

Take a look at our fantastic recipes for some ideas of healthy, delicious meals you can make.

1) 'Probiotic supplementation reduces the duration and incidence of infections but not severity in elite rugby union players' Journal of Science and Medicine in Sport

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