Are fermented foods good for my heart?

A selection of fermented foods. Clockwise from top left: Kimchi, beetroot, apple cider vinegar, pickles, sauerkraut, coconut milk yoghurt.

Senior Dietitian Victoria Taylor says:

Fermentation has been used to preserve foods for thousands of years. Some of these foods will be familiar, such as yoghurt, sauerkraut and crème fraîche. Others, such as kimchi (Korean fermented vegetables), kombucha (a drink made from fermented tea), miso (a Japanese flavouring made from fermented soya beans) and kefir (a fermented milk drink), are less well known.

Fermented foods can contain ‘probiotics’ – live bacteria and yeasts that are thought to have health benefits. This may make these foods a useful addition to our diets.

There are many health claims about them, from preventing cancer to reducing cholesterol and obesity, but most aren’t supported by research. There is some evidence linking certain probiotics with benefits for some digestive problems. More studies are needed to understand how the benefits of individual probiotics seen in clinical trials translate to eating these in foods – for example, we need to know how much we’d need to eat to see any benefit, or which foods are the best sources.

There are many health claims about fermented foods, but most aren’t supported by research

Although there is still much to learn about fermented foods, for most people there is no harm in trying them. Just remember that any benefit is an ‘add-on’ to a healthy balanced diet; they can’t counteract the effects of an otherwise unhealthy diet.

Check nutrition labels carefully and remember that fermented foods should be ‘live’ so need to be kept in the fridge. If they’re from a supermarket shelf, be wary – heat treatment that may be used to preserve these foods destroys probiotics.

Some of these foods, such as sauerkraut, kimchi and miso, are often salty, so check the label and choose reduced-salt versions if possible. A food is classed as ‘high’ in salt if it contains more than 1.5g (0.6g sodium) per 100g and ‘low’ if it has 0.3g (0.1g sodium) or less per 100g. If you’re buying yoghurt, choose low-fat versions without added sugar.

Victoria Taylor Meet the expert

Victoria Taylor is a registered dietitian with more than ten years’ experience. Her work for the NHS focused on weight management and community programmes for the prevention of cardiovascular disease. At the BHF she advises on diet and nutrition.

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