How Food Affects Your Mood
Have you ever felt butterflies in your stomach, or trusted your gut on a tough decision? If so, you are already familiar with the gut-brain connection! In fact, the gut is made up of over 1 million nerve cells, giving it the title of the body’s “second brain.” The link between your gastrointestinal tract and your brain lies in a series of pathways called the gut-brain axis. This line of communication connects intestinal functions with emotional centers of the brain. In other words, your digestive health directly affects your mental health.
One study revealed that 71% of patients with celiac disease showed high levels of anxiety, compared to the non-celiac control sample. Other research showed that 84% of a sample with irritable bowel syndrome (IBS) also faced depression. But what actually happens in the GI tract to produce psychological stress? Let’s break it down.
The gut microbiome: the living environment inside of you.
Did you know you have trillions of bacteria living inside of your intestinal tract? These microorganisms (aka microbiota) make up your gut microbiome. The microbiota are powerful agents that protect your gut against viruses, absorb nutrients, and maintain a healthy intestinal structure. However, the microbiome is home to both “good” and “bad” strains of bacteria. When the good bacteria outnumber the bad bacteria, your gut is in a state of symbiosis, and functioning normally. However when the bad strains outweigh the good ones, your gut enters a state of dysbiosis and can lead to a host of issues, including a condition called leaky gut syndrome.
Leaky gut, (intestinal permeability) appears as physical holes in the intestinal tract. Our digestive system’s lining acts as a barrier between the organs and the rest of the body. When working properly, this lining allows important nutrients to pass through and be absorbed into the bloodstream. This wall also holds back harmful waste that filters through the digestive organs and exits the body as feces.
When leaky gut is present, the gaps that are formed in the intestinal lining allow undigested food particles and toxins to pass through into the bloodstream and circulate throughout the body. The body then senses these foreign “invaders” and mounts an inflammatory response to attack and drive them out. When the body is inflamed, we often feel bloated, sluggish, foggy, anxious and unhappy…. which leads us to our next group of players in the gut-brain connection: neurotransmitters.
A closer look at “the happy hormone.”
In order to fully understand the gut-brain connection, we must look to our friend, serotonin, popularly dubbed the “happy hormone.” Many people know serotonin as the primary neurotransmitter responsible for positive mood, yet fewer know it’s birthplace. Over 90% of the body’s serotonin is produced in the intestinal tract, making a healthy gut vital for good serotonin levels! Once synthesized, serotonin sends signals from the gut to the brain via neurons, resulting in mood stabilization and healthy cognitive function.
However, when gut health is compromised (looking at you, leaky gut), serotonin production can be disrupted. Tryptophan, an amino acid found naturally in foods, is a key building block to serotonin. When the gut is in a state of dysbiosis, the microbiota can lose the ability to control tryptophan, therefore reducing the amount available for serotonin production.
Serotonin’s sidekick, (GABA) is also a neurotransmitter with beginnings in the gut. Good members of the microbiome are key in GABA production, yet can falter when their not-so-good counterparts overrun them. While serotonin is responsible for elevated mood, GABA works to produce a calming effect on the nervous system. Therefore, a lack of serotonin in the body can lead to depression, while a lack of GABA can cause anxiety.
So what can be done?
Mental health conditions such as depression and anxiety can feel frustrating and out of your control. However, there are several simple steps you can try to get to improve the gut-brain connection. Many think of depression and anxiety as diagnoses, yet they are often symptoms of something greater. With underlying factors being either physiological or lifestyle related. Medications such as SSRIs certainly have their time and place. However they typically treat the symptoms and never reach the root cause. Before filling a prescription, or to add to a medication routine, try these foundational tests:
Cut back on sugar.
The population of “bad” bacteria have quite the sweet tooth and love it when you indulge in that piece of cake, or add sugar to your coffee. In fact, the more sugar you consume, the more this bad population will grow, eventually taking over the good guys. An easy solution to maintain optimal gut health is to cut back on sugar, especially refined sugar and processed sweets (you CAN do it). Try switching to real, whole foods like dates or raw honey for your sweetener, or better yet avoid sugar all together. The best part? The less sugar you eat, the less you will crave it!
Increase food that can boost your mood.
If your gut is in a imbalanced state, production of key neurotransmitters may be suffering. It can be helpful to add foods to your diet that will help boost this production! Fill your plate with turkey, eggs and spinach that contain tryptophan. and add in probiotic-rich foods like kimchi or unsweetened yogurt that can feed good bacteria needed for GABA synthesis. Introducing a daily probiotic supplement to your routine can also help stabilize your gut. Before popping any probiotic however, it is good to know there are many varieties on the shelf that contain different bacteria strains – some that will help more than others, depending on your symptoms. To learn more about specific probiotics and how to take them, check out this article by functional doctor and gut expert, Mark Hyman.
Get tested for gut disorders.
It can be difficult to treat anxiety or depression if your symptoms are unknowingly caused by a food intolerance or gut disorder. To rule out these possibilities, ask your doctor to order tests for conditions such as celiac disease, lactose intolerance, bacteria overgrowth and parasites. However, it is important to note that even if these tests come back negative, it is still crucial to focus on gut health for optimal mental health!