Are fermented foods really worth the hype?
Fermentation is one healthy food trend that keeps growing. Dietitian Laura Tilt puts its touted nutritional benefits under the microscope.
If you thought the wellness world would swiftly get over sauerkraut and kombucha, you’re very much mistaken. Worldwide sales of fermented foods are expected to reach $52 billion in the next two years. Ready to geek out? Fermentation is an age-old practice that involves the controlled action of live microbes (bacteria and yeasts) to preserve food and enhance its flavour, texture and nutritional make-up. And fermented foods are hiding in plain sight – yoghurt, cheese, chocolate and coffee are all technically fermented. During fermentation, microbes (naturally present or added) consume sugars in foods they’re living on, such as dairy or vegetables, producing gases and acids. Microbial end products give fermented foods their fizz and tangy flavour – think of the tartness of yoghurt or the bitterness of kombucha – and create a preservative effect by lowering the pH, preventing the growth of harmful microbes.
While preservation was the initial draw, now it’s the potential health benefits. For instance, yoghurt has been associated with a lower risk of breast cancer, while kimchi has been linked with a lower incidence of asthma. It sounds promising, but other factors could be at play. It’s true, though, that fermentation improves your gut microbiome and the digestibility of some foods. For example, milk kefir is made with bacteria that breaks down lactose, making it more digestible for people with an intolerance. As for why you need a healthy gut microbiome? It forms a key part of your immune system, helps you digest food and influences mood and behaviour through the many neurotransmitters it produces. But antibiotics, low-fibre diets and stress disrupt this community. Enter the value of probiotics – live microbes that can boost your health when consumed in the right quantity. Because fermented foods are made with live microbes, it’s assumed these reach the gut after being eaten – and, yes, some studies support this. But should they reach their destination, the physiological effects aren’t fully understood.
While some fermented foods retain living microbes, such as raw sauerkraut (found in the fridge section of supermarkets), others undergo processing that renders them inactive. Soya and pasteurised sauerkraut (the cheaper stuff in jars on shelf ) are made stable by heat processing, but more studies on the health effects need to be done.
Though proven gut benefits are pending, fermented foods are still worth a shot. Sauerkraut is rich in fibre and vitamin C, and naturally carbonated fermented drinks contain less sugar than soft drinks. Don’t like kimchi? Try a carrot ’kraut. Dairy fan? Opt for milk kefir on your cereal. While we wait to learn more about the effects of ferments, they still have much to offer.