Fermented Foods vs. Probiotics

Kathy Wheddon Nutritional Therapist DipION

What are fermented foods?

Fermented foods are foods that have undergone a fermentation process, which involves being broken down by yeasts and bacteria. These foods are experiencing a current rise in popularity and they could well become categorised as the next ‘superfood’. The idea of fermenting foods is certainly not a new one, and in many countries such as Germany, Poland & Japan fermentation is a commonplace practice in every day eating. Find out more by reading about our five favourite fermented foods.

Six little bowls of various fermented foods.

Pickled turnips could provide key immune support in the fight against flu

Research into fermented foods

It was published in the mainstream press recently about the health benefits of pickled turnip juice for the immune system. A probiotic drink, made from traditional Japanese pickle (known as Suguri), has been investigated by scientists for its ability to prevent flu. The journal Letters of Microbiology published research indicating that the type of bacteria in the pickled turnip, Lactobacillus brevis, may prevent strains of the flu virus such as H1N1 and the deadly H7N9. The study resulted in the creation of more flu-fighting antibodies in mice.

Naoko Waki, from the food company Kagome who ran the study, states, “Our results show that when a particular strain of Lactobacillus brevis is eaten by mice, it has protective effects against influenza virus infection”.

Large scale studies are due to be carried out on humans, and scientists hope this may lead to a new range of flu-fighting foods containing the bacteria to come on the market.

The Sunday Times Style magazine in a 2020 article5 discussed the benefits of fermented foods, along with their celebrity following, such as kimchi (a spicy Korean sauerkraut), miso (a Japanese drink revered for its longevity benefits) and apple cider vinegar (highly regarded as a key digestive aid).

Wooden bowl full of miso soup.

Miso Soup is another fermented food with associated health benefits

So, how do you feel about eating pickled cabbage! Whilst many people in the West may baulk at the concept, without perhaps realising the nutritional benefits, we absolutely love fermented foods like kimchi and sauerkraut. Yoghurt itself is a obviously a widely accepted fermented food, and it plays a vital role in the history of probiotics.

The science of fermented foods

It can be helpful to learn a bit about the science of fermentation in order to understand how these foods can benefit our health.

The lactic acid produced during the fermentation process helps to digest other foods, such as proteins. The vegetables are left to ferment for a period of days or weeks, and are essentially pre-digested by bacteria and yeast which then helps with our absorption of their nutrients.

Fermentation also releases enzymes vital to the digestive process, which is one of the reasons that fermented foods are so beneficial to gut health. By improving gut health, many other sytems in the body are positively affected. For example our mental health and our immune health are intrinsically linked to gut health.

 Read more about these topics: gut-brain connection and how our gut health affects our mood. Healthcare Professionals can head over to our sister site to read: Gut bacteria's role in immune function.


China bowl full of sauerkraut

Are you tempted by sauerkraut?

Fermented foods vs. probiotics

Fermented foods are great and should certainly feature as part of a healthy diet, in order to introduce more live cultures into the body and help to support immunity.

I often recommend clients to enjoy the benefits of these foods. However, there are some limitations, so it's worth bearing in mind a few points. The most important one being that the cultures present in each batch of fermented food will vary - and this can make clinical trials on foods more difficult. Producers do not generally guarantee the number of live cultures in each batch, or indeed even the bacterial strains present in each batch.

So when it comes to finding a well researched strain of bacteria with a known (and clinically proven) associated human health benefit, a probiotic supplement which can give these essential details definitely has its benefits.

Optibac probiotics range
 Optibac Probiotics has an extensive range of well researched probiotics.

To learn more, you may like to read the following articles:

How do probiotics work?

Is wine a probiotic?

This blog was written by Kathy Wheddon, Nutritional Therapist DipION in collaboration with our lifestyle writer Jacob Collyer-Smith.


  1. N. Waki, N. Yajima, H. Suganuma, B.M. Buddle, D. Luo, A. Heiser, T. Zheng. Oral administration of Lactobacillus brevis KB290 to mice alleviates clinical symptoms following influenza virus infection. Letters in Applied Microbiology, 2013
  2. Image source: dailymail.co.uk
  3. brownricelife.com
  4. running.competitor.com
  5. https://www.thetimes.co.uk/article/unlock-the-secret-to-gut-friendly-loaves-and-fermented-veg-vmw3szfp0