Some foods commonly promoted for gut health may also carry risks for heart health if consumed in excess, the British Heart Foundation (BHF) has warned.

The charity said products marketed as prebiotic, probiotic or good for the gut in other ways can support the gut microbiome, but may also contain high levels of salt or sugar, which are linked to increased cardiovascular risk.

Foods highlighted include fermented products such as kimchi and sauerkraut, which are rich in beneficial bacteria but often high in salt, as well as kombucha and fruit yoghurts, which can contain added sugars.

Smoothies, while high in fibre and nutrients, can also lead to faster rises in blood sugar due to the breakdown of fruit structure during blending, the charity warned.

Supporting gut and heart health

Tracy Parker, nutrition lead at the BHF, said: ‘We encourage everyone to choose foods that can keep their gut microbiome healthy.

‘The benefits are clear, and we are continuing to improve our understanding of how a gut-friendly diet may help our hearts.

‘A lot of these products can contain high levels of salt or sugar though, so it is important to be aware of the potential drawbacks.’

The charity advises checking food labels for added salt and sugars and consuming these products in moderation to ensure the benefits to gut health are not offset by increased cardiovascular risk.

It also recommends choosing lower-sugar options such as plain yoghurt with live cultures, limiting smoothie portions to 150ml, and opting for lower-salt varieties of fermented foods where possible.

The advice comes amid growing interest in the role of the gut microbiome in overall health.

Beneficial gut bacteria are linked to reduced inflammation and improved metabolic and cardiovascular outcomes, while less favourable bacteria are associated with increased inflammation and changes in cholesterol processing.

The BHF said a varied diet rich in fibre – including wholegrains, beans, lentils, bananas and onions – remains key to supporting both gut and heart health.

A version of this article was originally published by our sister publication The Pharmacist.