Conscious eating, your friend in dark winter times – by Julia Rode
Winter blues? Yes, this February - in the middle of the dark season - it's easy to feel a bit down. Seasonal depression is actually common in Scandinavian countries. And even if you don't end up there, life is a bit slower right now. At least that's my perception. Even though I moved here more than eight years ago, I still lose the accurate perception of my circadian rhythm during the short winter days.
Original article: Medvetna kostvanor – din vän i mörka vintertider – Nerikes Allehanda
Did you know that how we feel mentally is influenced by our guts? There is scientific evidence that the composition of the gut microbiota can be disturbed in depression. While there is still no scientific definition of what a ‘healthy’ gut microbiota looks like, we do know that it is characterised by a high diversity of different bacteria.
During the dark and cold winter, it is therefore particularly important for us to look after our gut microbiota. It is largely influenced by your lifestyle - how you sleep, exercise and eat.
My research focuses on how diet, dietary products and supplements affect brain health - that is, how they contribute to a well-functioning brain that can cope with the demands of everyday life. Most recently, I researched probiotics. Probiotics are living microbes, usually bacteria, that have health benefits if we eat enough of them regularly.
There is a wide range of probiotics available, for example in powder, capsule or drink form. Some products contain single bacteria, while others contain a mixture, and all have different effects. Probiotics can have an impact by becoming part of the gut microbiota or by producing substances that benefit the microbes already present.
Our research examines the effects of probiotics on mental health and cognitive function, and how those interact. Cognitive function includes for instance memory, problem solving, orientation, concentration and attention. The overall aim is to find out whether probiotics can be used preventively to maintain good mental health and high cognitive function throughout adulthood, making us more resilient in challenging situations.
Usually, we ask healthy individuals to take probiotics for a certain period of time and monitor their health regularly. We use self-reported rating scales to measure mood, stress, sleep quality and cognition, amongst others. Ultimately, it is the subjective perceptions that influence each other and make the difference for us as individuals. We know what our mood can be like when we have not slept well.
In Örebro, we also have access to specialised research equipment to measure brain function objectively, both at rest and when participants are performing specific tasks. This helps us to detect effects even before they become visible on the above-mentioned rating scales. Changes in both measurements are closely related. It also helps us to formulate possible explanations for the biological mechanisms and clinical relevance of probiotic effects.
In our recent studies, we found that probiotics improved the regulation of negative emotions. The participants were completely healthy and showed no signs of anxiety or depression. Brain imaging showed that their brains seemed to work more efficiently, and the rating scales pointed in the right direction. We find it promising that such a simple and gentle intervention produced effects even in healthy individuals.
Of all the ways to target the gut microbiota, probiotics are the most studied in terms of the gut-brain connection. This is a good example of how diet and effects on the gut microbiota can affect our mental health. A similar approach may be to eat fermented foods, such as filmjölk or sauerkraut. As scientists, we are of course humbled - this research is important, but still only one of many factors that influence our health.
So, what can you do to beat the winter blues? What I can say is that you should find out what makes you feel best - because there is no one-size-fits-all solution. Diet and its effects are individual. In the future, we researchers hope to be able to assess who benefits most from a particular diet and make personalised recommendations. We already know that taking care of our gut can help us cope with stressful or emotionally difficult situations.
In German we say ‘the cobbler has the worst shoes’ - and that's how I felt the other day when I skipped breakfast, even though I know it's the most important meal for me personally. But that's okay. We don't always have to eat ‘perfectly’.
Translation of parts of the text was assisted by Deepl.com
How the gut microbiota is revealed
Scientists usually use faecal samples to draw conclusions about the gut microbiota inside the gut. Until now, we, however, have had no evidence that the faecal microbiota really reflects the gut microbiota. It was only recently that we were able to confirm in a study that a simple stool sample can reveal which bacteria are present in the gut of healthy individuals. This knowledge will improve the quality of the conclusions we can draw from our studies.