Breaking down 7 common myths about probiotics

Everyone seems to have an opinion about probiotics. But what does the science actually say?

Gut health can seem complicated. Misinformation, flashy trends, influencer scams, and unregulated products promising the world and delivering nothing.

But it doesn’t have to be confusing. We’re here to cut through the noise—shining a light on the facts and challenging the myths, misconceptions, and outright lies about probiotics, so you can make the right decision for your gut.

Myth 1: All bacteria are bad

Bacteria cause illness, right? Everyone knows that. It’s why antibiotics have made such a huge impact on public health.

But it’s not that simple. Less than 1% of known bacteria strains actually cause any form of illness at all. And many strains are symbiotic with humans—they live with us, and we both benefit. The best example of this is the gut.

Your gut contains trillions of bacteria, known as your microbiome, which affect digestive health, brain health, immune health, and more. Everyone’s microbiome is unique and, working with the brain (communicating via the gut-brain axis), produces neurotransmitters such as serotonin and dopamine to help us feel better.

Myth 2: Probiotics are only for people with gut issues

We used to think that only people who had gut symptoms would benefit, but the truth is everyone living a modern lifestyle is likely to get some benefit from taking a probiotic. Our gut controls so many different functions in our body, and the more we learn about it, and how it’s connected to the rest of our body, the more we understand how much it impacts every process in the body.

Science tells us that gut health is especially important for people who want to look after their mental health, as the brain and gut are inextricably linked through a network of nerves, hormones, and neurotransmitters known as the gut-brain axis.

Myth 3: Probiotic-rich foods are enough to make a difference

Your stomach acid kills most bacteria, and that’s what it’s supposed to do. It’s an essential part of your immune system.

But that’s a problem if you’re trying to get beneficial gut bacteria through the stomach, and into the gut alive. Unfortunately, even if you regularly eat food that’s teeming with beneficial bacteria—kimchi, sauerkraut, or kombucha, for example—there’s not much evidence to suggest any of the probiotics in the food make it to your gut, which is where they can make a difference.

Myth 4: Your stomach kills probiotics before they can work

It stands to reason then that probiotics are all useless. After all, the bacteria can’t survive your stomach, right? WRONG!

Bacteria on their own, without any protection, won’t survive your stomach acid. But if they’re contained in a delayed-release capsule that remains intact in the stomach and releases them in the gut, they can bypass the danger. On top of that, certain strains of beneficial bacteria have been developed to survive exceptionally acidic conditions, so a probiotic that uses these acid-resistant strains will be more likely to reach the gut alive.

Myth 5: All probiotics are the same

There are 30,000 named strains of bacteria, and at least 8,000 have been found in the human microbiome. That’s a lot of potential combinations.

Every probiotic supplement will contain a different formula, and the precise combination of live bacteria is essential to a probiotic’s effectiveness. Certain strains, such as CEREBIOME®, have bigger impacts than others, and some strains work better together—the trick is knowing how to put them together into a clean, high-impact formula.

Myth 6: The more CFUs the better

This isn’t necessarily a myth, but it isn’t necessarily true either.

The specific CFUs per strain is more important to know than a single overall figure. Many shady companies will hide this information, hoping that you don’t realise they’ve packed their supplement with huge amounts of largely useless bacteria.

That said, there is a minimum number of CFUs needed to maximise the likelihood of a supplement making a difference, so when choosing, aim for at least 10bn CFUs per dose. And it’s important to remember that the total CFUs in any supplement goes down over time, so the longer it’s sitting on a supermarket shelf, the lower that actual number will be. For the biggest impact, always look for the freshest probiotic supplement you can.

Myth 7: You need prebiotic supplements

Did you know that most of the symptoms blamed on probiotics (gas, bloating, indigestion) actually come from prebiotics?

And although prebiotics are an important part of any diet, you can’t fit enough into an easy-to-swallow capsule to make any difference at all?

So instead of trying to get a worse-than-useless amount of prebiotics from a supplement, aim for a food-first approach to prebiotics, based on a varied diet with lots of vegetables.

So next time you see a claim about what probiotics can or can’t do, ask yourself—what’s the science that backs it up?

Want to learn more about the science behind probiotics and mental health? Read our article here .


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