A Healthier Gut Microbiome

Maintaining a healthy mood

Written by Christina Brockett
8 min

Modern Stress

The alarm goes off, and you silence it. Later, you wake, look at it, and realize you’ve overslept; you’re late for a meeting, and panic starts. Your heart races, and you breathe faster as you rush to get ready. At that moment, you are grateful that they can’t see that you’re still wearing your pajama pants on the Zoom call. You join the meeting late and face a disapproving look from your boss. The muscles in your jaw clench as you attempt to smile; things are not going well. As the meeting continues, all you can think about is the muffin waiting for you in your kitchen. The cravings are annoying, and as soon as the call is over, you race to eat it. While eating the muffin, you scroll Instagram and see a post of your ex on vacation. The very vacation you were to go on together. You wish there were more muffins.

These minor stressors add up and reflect what we know as everyday stress; it is inescapable.

Stress: A Normal Response

Stress is a normal response to a physical, psychological, or environmental threat. The threat may be actual, like seeing an oncoming car run through a traffic light, or mental like the example above. Regardless, your body follows a similar pathway as it triggers what is known as the fight-or-flight response. This response was designed to give us bursts of energy to handle threats to our survival and then turn them off.

When a stressful event happens, the amygdala, the part of the brain which processes fear and emotions, receives information. Sometimes this happens and we aren't even aware that we feel afraid. The amygdala processes the data, and if it thinks the body faces danger, it sends an urgent signal to the hypothalamus, the area in the brain responsible for keeping the body in balance. In response, the hypothalamus sends messages through the nervous system, triggering the body’s fight-or-flight response. The adrenal glands respond by pumping out noradrenaline and adrenaline, making the heart beat faster and increasing blood pressure. Then blood sugar and fats release into the body, supplying it with energy to help respond to the threat. As the initial surge of adrenaline subsides, a second component of the stress response, the HPA axis, activates.

The hypothalamus, pituitary, and adrenal glands comprise the HPA axis. This secondary stress response helps the body handle prolonged or continued stressors. This response keeps the heightened fight-or-flight response going via a series of hormones released from the hypothalamus and pituitary. These hormones prompt the adrenal glands to release cortisol. In this stage, proteins and fats break down into glucose for energy. There is also an increase in blood sugar and suppression of the immune system. When the threat passes, cortisol levels will drop, and the rest-and-digest side of the nervous system will put the brakes on the process.

The Problem is in Faulty Brakes

The problem is that most people have a hard time putting the brakes on stress. Instead of the system operating as designed to address a threat, or acute stessor, and return to a standard or relaxed state, we experience intermittent, chronic stress. When we experience recurrent stressors for too long, the HPA axis never entirely turns off. As a result, we experience ongoing adrenaline surges, damaging blood vessels and arteries, which leads to increased blood pressure and cardiovascular risks.

The continuous increases in cortisol cannot drop and clear from the body properly and remain elevated. Normally, increases in cortisol help you recover from depletions during a stressful event by increasing your appetite and then triggering fat cells to store unused energy as fat for later use. The problem is that without a sound brake system, this process continues. Instead of letting cortisol levels shrink, we reach for muffins while our waistlines expand.

The Inflammation and Stress Link

There is a link between inflammation and stress. As the stress response continues, levels of cortisol are higher than usual. As a result, it is harder for the body to manage its inflammatory and immune responses. With chronic stress, even the cells may become less sensitive to cortisol, and inflammation can get out of control (Cohen et al., 2012). As acute inflammation increases, it lays the groundwork for stress-related disease development. The activation of the body’s stress system is associated with a notable estimated 75-90% of human diseases (Liu et al., 2017).

Stress increases the risk of getting a disease that makes you sick, or if you already have a preexisting condition, increases the risk that the disease state might worsen. Conditions associated with stress include1:
Cancer (Pancreatic, Breast, Lunch, Acute Lymphoblastic Leukemia, Hepatocellular Carcinoma)
Cardiovascular Disease (Hypertension, Atherosclerosis)
→ Fibromyalgia
→ Inflammatory Bowel Syndrome
Irritable Bowel Syndrome
Menstrual Irregularities
→ Metabolic Diseases (Obesity, Type 2 Diabetes, Metabolic Syndrome, Dyslipidemia)
Neurological Disease and Issues (Dementia, Depression, Headaches, Parkinson’s and Brain Composition Changes)
→ Rheumatoid Arthritis
→ Ulcers

Stress Can Alter Your Gut Microbiome

Alterations in our gut microbiome, or even our nutrient levels when stressed, should not come as a surprise. Take a moment and think about it. You’re stressed about giving that presentation. Knots take over your stomach, and that breakfast eaten an hour ago seems to be just sitting there. The urge to go to the bathroom comes, yet you cannot go despite trying. You give the presentation and then think nothing more about it. Then you get back to your computer only to realize your boss assigned yet another project, which will require late hours. This will mean caffeine and fast food are on the menu for dinner. You know it isn’t the healthiest, but your options feel limited.

While you might have experienced a change in how your gut felt, you may not have realized the substantial impact that stress was having on your digestive health. Stress can alter a variety of things, such as2:

→ How fast things move through your system and how well you can eliminate them.
→ The amount of the digestive secretions that help break food down, so the food doesn’t feel like it is “sitting there.”
→ The healing and overall health of your gut tissue. Which, when unhealthier, can be more permeable, commonly known as “leaky gut.”
→ The composition of the gut microbiota. The microbiota consists of the bacteria, viruses, and fungi that occupy your gut.
→ The production of short-chain fatty acids. These are made by the friendly bacteria in your gut and impact overall gut health.

That stressful scenario may have led to more than just poor food choices. All the stress you’ve experienced is not only affecting your immune system but also depleting your body of a variety of nutrients, including:
→ B Vitamins
→ Vitamin C
→ Magnesium
→ Potassium
→ Zinc

It’s All Interconnected

Research is gradually showing how
interconnected our health is. Stress influences inflammation, nutrient depletion, and gut health. An unhealthy gut increases inflammation, negatively impacting mood, making it challenging to cope with stressful situations. Because this impacts our mental health, it becomes more difficult to maintain a healthy diet. When we eat unhealthy foods, they upset the healthy balance of our gut bacteria and reduce the healthy levels of short-chain fatty acids and nutrients. This imbalance can lead to decreased gut health and inflammatory diseases. These all-combined increase stress on our bodies.

Are your stress levels impacting your gut health? Stop guessing. Start testing. Take a Gut+ microbiome test and find out today!


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1. Hassett & Clauw, 2010; Innala et al., 2016; Kokubun et al., 2018; Liu et al., 2017; Murray & Pizzorno, 2021; Vannucchi & Evangelista, 2018

2. Konturek et al., 2011; Maltz et al., 2019

3. McCleane & Watters, 1990; Weatherby, 2004