The gut microbiota does more than just help with the digestive process; it also plays an important role in our overall health. Emerging researches show that in addition to these, probiotics also bring beneficial effects on mental health, which in turn affects one’s mood and emotions. This is due in part to how inextricably linked the digestive system is with your brain, primarily via the enteric nervous system (ENS), which is a complex network of millions of neurons.
The ENS also controls the muscles in the gastrointestinal tract and it controls when to secrete certain hormones such as gastrin (signals the secretion of gastric acid when you eat), cholecystokinin (stimulates the secretion of pancreatic enzymes and bile), and secretin (stimulates the secretion of a bicarbonate-rich fluids from the pancreas and liver to prevent gastric acid from harming your intestines). This control is important in order for the digestive system to function optimally.
Several studies have shown that both your emotional well-being and moods can be influenced by your gut microbiota, the bacteria that live in your digestive system. Good bacteria such as Lactobacillus and Bifidobacterium also produce neurochemicals such as Gamma-Aminobutyric Acid (GABA), which is believed to help improve moods or lead to a calm and relaxed feeling. Low levels of GABA are linked to anxiety or mood disorders, epilepsy, and chronic pain. Serotonin is another important neurochemical that the gut microbiota produces which is important in balancing mood; a lack of serotonin can lead to depression.
This shows how the gut microbiota plays an important role in the production of neurochemicals which help regulate basic physiological processes by the brain, thus an imbalance in gut microbiota may have dire consequences such as depression, autism spectrum disorder, anxiety disorders, mood instability, stress levels, and even poor quality of sleep. This means that having a well-balanced between good and bad gut microbiota is important not just for overall physical health, but also for maintaining emotional health, as it allows you to better handle stress and can improve your mood.
A study on patients with chronic constipation found a link between psychiatric disorders and chronic functional constipation. The study uncovered the fact that prevalence of mood and anxiety disorders in constipated patients is much higher than the general population. Anxiety and depression rates were found to be at 34.6% and 23.5% respectively in patients with chronic constipation, whereas rates in the general population were at 4.35%, and 8.31% respectively.
Similar studies by other researchers have also found proof that gut microbiota can influence stress responses. While the majority of studies used laboratory mice, a study on humans which used functional magnetic resonance imaging (fMRI) scans to assess the results found similar results. Twice daily consumption of probiotic yogurt over four weeks revealed a reduced brain response to negative images.
“These studies show a promising effect for future patients with depression or anxiety disorders. It could mean eliminating or reducing the need for pharmacological agents and focusing on dietary changes to include the probiotic of the specific strain you need which can then improve your mental health, and your mood,” explains Consultant Physician and Gastroenterologist Associate Professor Dr Raja Affendi Raja Ali from Hospital Canselor Tuanku Muhriz, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM).
While all these studies on probiotics do reveal their benefits, it also serves to highlight that our knowledge and understanding of probiotics is still far from complete. With so much more that we have yet to discover about the impact of probiotics on our health, more research is needed.
Landmark Local Research
In a bid to uncover more on the effectiveness of probiotics, local researchers from PPUKM are conducting an ongoing local study right here. The research team, led by Assoc Prof Dr Raja Affendi, have thus far discovered evidence that the Lactobacillus acidophilus and Lactobacillus casei strains are noticeably effective in promoting better digestive health. In addition, the two strains have also shown great potential to bring positive influences to the immune system in certain subjects.
The early results of the ongoing study have shown improvements in digestive health. Most notable of all is the improvement in reduced intestinal transit time (ITT), or the time it takes for food to travel from your mouth through your digestive tract and out of your body through your rectum. Another important initial result of the research includes marked improved constipation symptoms among subjects who are healthy and in those who have constipation. As a result of improved ITT, there is also a potential reduction in toxin build-up caused by constipation, thus allowing the digestive system to better absorb food nutrients more effectively. Lastly, daily consumption of cultured milk drinks with Lactobacillus acidophilus and Lactobacillus casei strains has also been shown to have a positive influence on the immune system in certain research subjects. However, this still bears future exploration and more data is needed.
In order to get enough probiotics, you should include foods such as cultured milk drinks, yogurt, tempeh, and fermented vegetables (e.g. kimchi or acar) in your diet. However, probiotics need prebiotics to support their growth. Thus, you should include prebiotic-rich foods in your diet, which consists of high fibre foods such as whole grains, onions, garlic, banana, shallots, leeks and asparagus.
“I strongly believe that probiotics such as Lactobacillus represent a safe and effective way and potentially can improve your mood while simultaneously benefiting your digestive system. Since both are very closely linked, maintaining one in good working order helps maintain the other. Of course, you should also take care of your health by eating healthily, enough sleep, and ensuring that you get plenty of daily physical activity or exercise,” advises Assoc Prof Dr Raja Affendi.
“In today’s fast-paced and hectic lifestyle, there is no way to avoid stress, thus it is important to learn how to manage your stress properly. It could be something as simple as listening to music, playing musical instruments, gardening, going for a walk in the park or even baking a cake; regardless of the method, the main thing is to find something that works for you and more importantly to enjoy your work!” states Assoc Prof Dr Raja Affendi.