Psychoneuroimmunology and Probiotics

Written in collaboration with Chris Habib, ND

Ever imagined a wonderful vacation in your head before it happened? Ever had a first kiss and replayed the moment in your mind? Ever had big event approaching that you are mentally rehearsing everyday, replaying every scenario in your head? Everyone has. Worry is wistful. It’s living that stressful situation one too many times: once in real life, once or more in your head. Our minds have incredible and inventive imaginary capacities. At its peak at five years old, we dream up impossible and somewhat illogical stories of dragons, pirates, and genies—but I don’t think adults are all that different. Adults have similar imaginary capabilities to consider more real-life scenarios, that which has not happened yet.

Mind-Body Connection

Being a fourth-year medical student, I am fascinated by the mind and its undeniable effects on the body. In particular, the study of psychoneuroimmunology is a field that recognizes these interrelationships of how our thoughts, emotions, and behaviours impact our physiology including our immune system.[1–3] Essentially, when we feel happy, our feel-good hormones increase and our stress hormones decrease, resulting in benefits to our physical body. When we physically feel healthy, our emotional state is often cheerful. Interestingly, the opposite is also true: negative thoughts can negatively affect the physical body, leading to a defeated immune system. Is it any wonder why everyone seems to get sick near finals week or around stressful seasons like Christmas time?

That means our thoughts can have a direct influence on how susceptible we are to getting sick. Negative, depressive thoughts have correlations with probiotics found in our gut, which in turn impacts our digestion.[6] It’s no wonder that those suffering with depression also have digestive issues. The opposite is also true: those studied who consumed probiotic foods had established healthy bacteria, and as a result had better brain function.[4] Other sources agree, showing probiotics can lead to improved mood and might be a good way to fight anxiety or depression.[6] Sugar is also known to grow “bad bacteria” which defeat the good bacteria or probiotics. Sugar can give an instant happy energy from the rise in blood sugar, but can ultimately impact gut bacteria and thus, later lead to lowered moods. A report from UCLA said that “researchers have known that the brain sends signals to your gut, which is why stress and other emotions can contribute to gastrointestinal symptoms. This study shows what has been suspected but until now had been proved only in animal studies: that signals travel the opposite way as well. Our study shows that the gut–brain connection is a two-way street.”[5]

To Eat or Not To Eat

The composition of our diet can even affect our microbiome. Obese individuals have been found to have different amounts of certain bacteria, which causes them to extract more calories than someone with less of those bacteria present. Also, a vegetablerich, fibre-based diet creates a different composition of microbiota, or gut environment, than someone who consumes a more typical Western diet that is high in fat and carbohydrates.[4] Another reason why vegetables are good for you! The presence or absence of certain gut bacteria are also associated with important neurotransmitters like GABA and serotonin, which affect mood and alertness. Researchers found the probiotic Lactobacillus rhamnosus has a large effect on GABA, an inhibitory neurotransmitter that helps calm the brain down to relax or sleep.[4]

Move Like You Mean It

Posture also has implications on depression and positivity. One study published in Health Psychology found that individuals with poor posture had more depressive thoughts, which leads to further questions to research within mind-body medicine.

Yoga is a powerful way to strengthen muscles, improve flexibility, and—as a wonderful side effect—improve posture. An hour of yoga can increase brain GABA levels (mentioned above) by 27%! GABA stands for gamma-aminobutyric acid, the main inhibitory neurotransmitter in the brain. Its primary role is to calm, slow things down in the body, and relax an individual. Insufficient levels can lead to anxiety, panic attacks, nervousness, aggressive behaviour, depression, and antisocial behaviour as in ADD and autism-spectrum disorder.[9] Interestingly, too little GABA can also contribute to alcoholism, drug addiction, and cravings for sugar and carbs, which temporarily increase GABA, so one is unconsciously drawn to them. In this 2007 study, GABA levels were measured by magnetic resonance imaging before and after either an hour of yoga or an hour of reading a book. The yoga group had a 27% increase in GABA, while the reading group remained unchanged.[9] All the more reason to get on with those sun salutations and downward dogs!

Travel and Gut Bacteria: Cutting-Edge Findings

Traveling is alluring for “young old” (think newly retired), but you might want to think twice, according to the latest research, which uncovered that tourists can pick up antibiotic-resistant genes in their gut in just two days. In this study, 122 travelers showed that the proportion of antibiotic-resistance genes in their gut bacteria increased from below 10% before they left to as much as 55% on their return. Antibiotics resistance is a whole separate topic. Rest assured; none of the travelers in the study suffered any ill effects from the newly acquired genes. So not to worry, except for in immune compromised individuals or those that are already on antibiotics.[7]

Feeding the Good Guys

If you want plants to grow, they need water and sun. They need food and nourishment to expand their roots, and energy to produce leaves, fruit, or flowers. Probiotics, or good bacteria, are no different. “Probiotic” actually translates to “for life.” Prebiotics, on the other hand, are a less-known, but hugely valuable part of having a healthy gut bacteria. They are the food for probiotics to eat and take habitat.[8] Prebiotics stimulate growth of probiotics. Essentially, prebiotics are small, non-digestible, insoluble fibres. Foods with fibre, like vegetables or flaxseed, can help create a substrate for probiotics to expand their numbers in your gut. Practically speaking, artichokes, onions, leeks, and asparagus are all foods that contain prebiotics, so emphasize these foods in your diet. Other ingredients on a label that indicate probiotics are FOS or inulin. There is also such thing as synbiotics, which are combinations of prebiotics and probiotics that are designed to have synergistic and/or additive effects benefiting the host.[8]

Goals and Health Woes

How does all this talk about the gut affecting the mind actually relate to our physical health goals? If we have stronger immune systems, we are likely to stay healthy and therefore able to be active, making and keeping appointments to a gym, a workout body, or exercising outside. Positive thoughts make us more motivated to exercise and move in the first place. In turn, this hitting the gym will give us more positive emotions, called endorphins, which further increases our motivation level—transcending fitness, permeating into every area of our life. This knowledge of psychoneuroimmunology, when harnessed and paired with imagination, can work to our advantage in generating health goals. We can “trick our mind” to believe that we are already there. We know that the mind can’t distinguish between an actual scenario and a mentally rehearsed, imagined scenario. It accepts a perception as reality—whether it’s actually true or not. Envision the best, healthiest, most energetic self possible. The real power comes with action based on that vision; that reinforces our resolve to create it. For many, it takes being at the lowest of lows to develop an inspiring image of a healthier future self. The highest weight, the worst fatigue, the digestive issues, the frustration of missing out; sometimes, these emotions occur and just invigorate us to seek options that will generate a better bill of health. It’s possible to train the mind into believing and feeling like an event or goal has already happened. One option is to create a vision board of what that looks like. This goal of exactly which landmark we want to achieve can be discussed with a friend or written down in detail. When picturing it happening in our “mind’s eye,” we train our brain to create a new perception. This is the realized power of meditation in the practice of lifestyle transformation.

Internal and External Force

Ideally, the most effective method to address any imbalance is both internally and externally. This model of wellbeing is holistic—considering the entire body and spirit— by engaging your body, you can affect the mind and vice versa. Altering physical movement by way of exercise and changing ergonomics can be a powerful route to shifting your internal dialogue. It’s possible to generate positive emotions by improving posture, which is best achieved incorporating yoga to strengthen structural imbalances. If anything, I hope I’ve convinced you that everything is related: poor posture affects a person’s mood and can lead to feelings of depression or decreased energy. Depressive thoughts affect our immune system, namely our gut, which can negatively affect our good bacteria of probiotics. Altered gut bacteria are linked to depression and other illnesses. According to research, consuming probiotics can be one solution. But the holistic approach, which is most likely to succeed, attacks a problem at every angle. If your gut and digestion aren’t healthy, your overall health probably isn’t either, as the gut is the foundation of wellness.

If you need help sorting this out, find a naturopathic physician who can bring clarity to what’s happening with your internal biochemistry and get to the root of the problem, solving it from the inside out. Life is lived forward but understood backwards. My hope is this article brought insight that helps you to understand the wellbeing of your body and mind in retrospect—but also for the fullness of life yet to live. Keep thinking big and living bold!