At a time when everything old is new again, we’re rediscovering the very modern health benefits of a group of ancient foods.
We’re used to hearing that fresh is best, but some ‘aged’ foods could be just as healthy. New research suggests that eating fermented (or cultured) foods, which are left to develop certain qualities, could provide important health benefits.
Our ancestors often prepared and ate foods such as yoghurt, sourdough bread and pickled vegetables. Today, as we learn just how healthy these foods are, the practice of fermentation and this way of eating are enjoying renewed popularity.
Basically, fermented foods are foods that have been left for days, weeks or even months to let the ‘good’ bacteria and yeast that live on their surface break down their natural sugars and starches, turning them into acids and gas — and giving them that distinctive tang. Fermentation not only makes food easier to digest, but also helps the gut absorb more of the foods’ nutrients.
How they soothe tummy troubles
Some fermented foods are sources of probiotics — ‘good’ bacteria that thrive in the gut, where they assist with digestion. An extensive amount of research has focused on (and continues to explore) all the health benefits of these gut-friendly bugs, because trillions of microbes call our large intestine home.
The gut contains both ‘good’ and ‘bad’ bacteria, but when this intestinal balance is out of whack, we become more vulnerable to constipation and irritable-bowel syndrome, among other digestive woes. Of course, the good news is that we can also experience the exact opposite. When your gut flora flourishes, you’re much less likely to suffer from such troubles. Intestinal flora also plays a key role in immunity, helping defend the body from infection.
The power of sour
Scientists are still busy exploring the benefits of fermented foods’ friendly bacteria, but here’s what we know right now: These foods help protect and strengthen the lining of the digestive tract. This helps prevent unwanted toxins (which are products of gas and faeces) from passing through the bowel wall into the bloodstream. Fermented foods may also have cancer-fighting properties and help reduce inflammation in the body. (Chronic inflammation is the spark that ignites cancer.)
Interestingly, a 2014 UK study shows that regular consumption of fermented low-fat dairy foods, including yoghurt and cottage cheese, can reduce the risk of developing type 2 diabetes. And a 2011 review suggests that a diet rich in lactobacillus bacteria can relieve lactose intolerance allergies and stomach ulcers, and even help prevent bowel cancer.
When more is more
So how much fermented food should you be eating to grow your healthy gut flora? Actually, there’s no simple answer.
Many fermented foods are good sources of probiotics, but it’s impossible to measure their number of ‘good’ bacteria. On top of that, these bacteria come in thousands of varieties, each of which behaves differently, and different foods have their own ‘cultural mix’ of these bacteria! So basically, the more fermented foods you eat the better.
If you’ve recently finished a course of antibiotics or suffered a bout of gastro, you might want to consider taking a probiotic supplement to ensure your gut is getting enough friendly bugs.
Easy ways to get your fermented fix
For Australians, the most familiar fermented food is yoghurt, which is a tasty combination of milk and a starter culture. You may have also tried sauerkraut, a traditional German dish of chopped pickled cabbage; kimchi, a spicy pickled cabbage from Korea; or miso, a versatile Japanese paste made of fermented soybeans and rice malt or barley. (See box below for details on kimchi and miso.) Unfortunately, the packaged versions of sauerkraut and other pickled vegies in supermarkets are heat treated, a process that damages their probiotic benefits. To reap the most health rewards, keep an eye out for the fresh stuff or simply make it yourself!
Not a fan of fermented foods’ tang? Try sourdough bread and cottage cheese, which are some of the more palatable options. Of course, these healthy foods may already feature in your diet!
Try these fermented foods
This creamy stuff is a staple food in most households, but you may have never thought of your regular tub of yoghurt as fermented milk.
Choose the best: All yoghurts contain a starter culture, but to enjoy the most digestive-health benefits, you need a brand with added probiotics. Look for brands that contain the cultures Lactobacillus, Lactobacillus acidophilus, Bifidobacterium bifidum and Lactobacillus casei.
Drained skim-milk curds and their remaining whey give this cheese its characteristic loose, pebbly texture.
Choose the best: Some brands of cottage cheese can be high in sodium, so pick a reduced-salt variety. Try this incredibly sustaining food with grainy crackers at lunch, or with roast sweet potato as a nutritious dinner.
A starter culture of flour and water ferments to create yeast and lactic acid, giving this chewy bread its slightly sour flavour and a low GI.
Choose the best: An authentic sourdough starter takes time to ferment, so some bakers add vinegar to simulate this bread’s sour taste. Traditional slow fermentation produces the most nutritious sourdough, so check ingredients lists and be wary of additives, too.
To make kimchi, Koreans add a paste of chilli, garlic and fish sauce to salted cabbage, then leave the mixture to ferment, sometimes for several months.
Choose the best: Think of kimchi as Korea’s take on sauerkraut. This spicy hot cabbage has become very popular in Korean restaurants here, so why not order it as a side dish on your next visit? Or look for low-sodium varieties in Asian food stores.
Tempeh and miso paste
These fermented-soybean products regularly feature in Asian-style dishes.
Choose the best: Use tempeh to replace meat in stir-fries and Thai curries. Miso paste makes a delicious simple marinade for meat and fish. (You’ll find tempeh near tofu in supermarket refrigerators, and look for miso paste in the Asian-food aisle or Japanese food stores.)