Their research offers fresh insights into how certain food components can enhance beneficial gut microbes while suppressing harmful ones, towards improving health.

In 2015, Forssten and her colleagues explored the potential of combining probiotics with a type of dietary fibre called polydextrose to combat Clostridioides difficile – a bacterium more commonly referred to as C. diff that causes severe diarrhoea, especially after antibiotic use.

Using a sophisticated lab model that simulates the human colon, they discovered that polydextrose altered the microbial environment, significantly reducing levels of C. diff while also promoting the growth of helpful bacteria. The team’s results highlight the potential of polydextrose to act as an effective bacterial modulator in the gut.

The following year, Forssten and her colleagues expanded on this work by investigating the metabolic effects of polydextrose in the gut. Using cutting-edge techniques, they examined how this fibre influenced gut microbial activity and the production of metabolic substances.

They found that polydextrose fermentation increased levels of healthy short-chain fatty acids that are known for their anti-inflammatory and gut-soothing properties. At the same time, levels of potentially harmful biogenic amines were reduced. These results highlighted polydextrose’s ability to promote a healthier gut environment, offering benefits that extend beyond digestion to overall health.

In their most recent study, published in 2023, Forssten and her team investigated a probiotic bacterium called Bifidobacterium lactis, and how different foods can influence its delivery to the gut. Using a laboratory system that simulates human digestion, they delivered the probiotic in a range of foods, including yogurts, chocolate and juice. They also assessed the effectiveness of typical probiotic-delivery methods, such as capsules containing freeze-dried bacteria.

The study revealed that most of these formats successfully delivered the probiotic to the colon. Interestingly, non-dairy yogurts, such as oat-based yogurt, and capsules containing freeze-dried bacteria had the highest success. Intriguingly, the researchers also found that the oat yogurt itself led to increases in beneficial short-chain fatty acids. These findings underscore the importance of not only the probiotic strain but also the food vehicle in achieving maximum health benefits.

Through their pioneering research, Forssten and her colleagues have gained valuable insights into how probiotics, fibres such as polydextrose and other dietary components work together to shape the gut microbiome. They are now taking their work further, by applying it to clinical trials. This research paves the way for innovative dietary strategies that empower individuals to take charge of their gut and thereby their general health.