From our mood to our skin health, everything starts in the gut. More of us now understand this core tenet of our wellbeing and act accordingly – doing what we can to feed the good bacteria in our microbiomes. But, as is so often the case, sometimes we over-complicate matters. I realised I might be guilty of the same when scientist and dietitian Dr Emily Leeming’s Substack newsletter, Second Brain, dropped into my inbox the other day. In it, she outlined the probiotic power – 100 million microbes worth – of the humble apple.
Glorious, crunchy apples. Infinitely cheaper than probiotic supplements, the apple is packed with hundreds of millions of microbes – just like other fruits and vegetables, all of which contribute bacteria to the microbiome. “Apples contain fibre, and particularly a probiotic fibre called pectin, that feeds your ‘good’ gut bacteria,” says Dr Leeming, whose forthcoming book Genius Gut: How to Eat For Your Second Brain, comes out in July. “It also contains plenty of polyphenols, which have a prebiotic effect on the gut microbiome.”
The growing obsession with probiotics means many of us could be tempted to prioritise taking a supplement over incorporating more microbe-rich plants into our diets – but you can’t out-supplement an unhealthy lifestyle. Many of us don’t actually need to be taking them in the first place. Yes, taking certain strains of bacteria via (evidence-based and well-made) probiotics can help us treat health issues, such as IBS-related bloating, or aid the microbiome’s recovery after taking antibiotics, but Dr Leeming says you “don’t need to take a probiotic supplement if you’re already well and just generally want to support your gut microbiome. What you eat has a far bigger impact,” she says.
Leeming describes the probiotic supplement market as the “wild west”. Many brands make big claims with scant evidence to support them. Some of the bad supplements on the market contain multiple types of probiotic bacteria, which haven’t been tested as a combination – and they can act differently when put together. Others have been shown to deliver the opposite effect to what they promise on the box. “As an example, cognition may get worse rather than better, or the gut microbiome may recover slower after antibiotics,” she warns.
But you can’t go wrong with the health benefits of an apple – or, indeed, any fruit or vegetable. Experts now recommend eating at least 30 different plants a week – including spices, herbs, legumes and grains, alongside fruit and vegetables – to improve your gut health. There is clear evidence that demonstrates how impactful fibre and polyphenols are on feeding the gut microbiome, so aim to incorporate more plants into your diet each day to nourish yourself. It really is as easy as that.
“We don’t yet know if organic fruit and vegetables contain more microbes than non-organic and if that makes a difference to the gut microbiome,” adds Dr Leeming. “But soil health likely plays a huge role in how microbe-rich the foods we eat are, particularly for fruit and veg that are grown close to or in the soil, like root vegetables – soil is particularly dense in microbes. One teaspoon of soil contains more microbes than people on the planet.”