Warning issued over 5 gut-friendly foods – there’s a huge catch

Foods marketed as “gut-friendly” — including kimchi, kombucha and fruit yoghurts — may contain hidden heart health risks, according to experts. The British Heart Foundation (BHF) warned that some products can contain high levels of salt or sugar. Eating too much salt can raise blood pressure, while excessive sugar intake can fuel weight gain, the charity said.

Tracy Parker, the BHF’s nutrition lead, 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.

“By ensuring you check package labels for added salt and sugars, and eat each in moderation, you can make sure the risks do not outweigh the benefits for your heart health.”

Here’s the BHF’s full advice on what to look out for:

Kimchi

Fermented foods like kimchi are rich in probiotics, the healthy bacteria produced during fermentation that can help support a diverse and healthy gut microbiome.

However, traditional kimchi is often made with a lot of salt, so it can raise blood pressure if eaten frequently or in large quantities.

High blood pressure is known to increase your risk of having a heart attack or stroke. To help keep your salt intake low, the British Heart Foundation advises enjoying kimchi in small portions and checking labels for lower-salt varieties.

Kombucha

Kombucha, a fermented tea, also contains probiotics and can help your gut in a similar way to kimchi.

It can be a healthier alternative to sugary or fizzy drinks and has become a popular choice for people looking to introduce fermented products into their daily routine.

But many commercial kombucha products contain added sugars. Eating too much sugar can lead to weight gain, which in turn can increase the risk of a heart attack or stroke or other cardiovascular disease. That’s why BHF encourages people to choose lower sugar varieties, often labelled as « no added sugar ».

Fruit Yoghurts

Plain yoghurt also naturally contains probiotic live cultures that can boost levels of helpful bacteria in the gut. Yoghurt is also a good source of calcium and protein. However, many flavoured or fruit-based yoghurts contain added sugars and may have fewer live cultures than plain versions.

The BHF recommends choosing plain yoghurt with “live and active cultures” mentioned on the label to ensure you are buying a low sugar option that is good for your gut. You can add whole fruit at home for a healthier way to add sweetness.

Smoothies

Smoothies made with whole fruits provide prebiotic fibre that feeds the beneficial gut bacteria and supports digestive health. They also offer a range of vitamins and antioxidants, especially when prepared with a variety of plant-based ingredients.

But blending breaks down the structure of fruit, releasing “free sugars” that behave like added sugars in the body and cause faster rises in blood sugar levels. Regularly consuming too much sugar can lead to weight gain, which can increase the risk of developing type 2 diabetes, heart and kidney disease.

Only one 150ml serving of any smoothie counts towards your 5-a-day, so the BHF recommends sticking to that portion size. It can also be good to add nuts or seeds for extra protein and fibre, which can help keep blood sugar levels more stable.

Sauerkraut

Much like kimchi, sauerkraut is a fermented food and so naturally very rich in healthy probiotics. However, also like kimchi, traditional sauerkraut relies on lots of salt for fermentation, which may be a concern for anyone watching their blood pressure. Some shop-bought versions are also pasteurised, which removes most of the live bacteria.

To avoid overdoing the salt, it’s worth checking the label and eating small portions only. If you want the beneficial probiotics, make sure you are getting unpasteurised sauerkraut — it’s generally fine for most healthy adults. Look for phrases like “raw”, “unpasteurised” or “contains live cultures” on the packaging.