Stress and The Female Gut Microbiome

Stress and The Female Gut Microbiome

There are many benefits to having a well-tuned acute stress response system. If we didn’t have this alarm system which was perfected in evolution over millions of years, our species would have long disappeared from the planet. In its simplest terms, the fight or flight response has saved our ancestors from being eaten by tigers, and our soldiers from being killed in combat. In moderate amounts, acute stress can positively affect our attention, reaction time and even boost memory. However, once short, transient spurts turn into prolonged and recurrent bouts, a situation called allostatic load, we render ourselves susceptible to a host of different issues. Our guts can be first to report a problem while also providing an entry point for a potent solution.

Bloating, changes in motility, and intestinal permeability are all associated with recurrent or extended stress exposure. While acute severe stress leads to an increase in cortisol levels in the blood, and to a dysregulation of the gastrointestinal (GI) tract by the autonomic nervous system, allostatic load-type stress is associated with an activation of the immune system, including the 70% of immune cells located in our gut. With the gut-brain axis being a bidirectional highway, engagement of the immune system in the gut tells the brain that the body is under attack and so begins a vicious cycle. For this reason, it is ever so important to understand how to mitigate our prolonged-stress response in order to protect ourselves against GI disturbances.

Eating foods that promote the proliferation of anti-inflammatory microbes (those that produce anti-inflammatory short chain fatty acids) and fight inflammation and is one of a suite of solutions we should tap into during periods of heightened stress. Understandably, stress-relieving foods fall in line with Mediterranean diet – touted as the diet to adhere to for best gut and brain health.

Now, while this is what we should adhere to, studies have shown that when stressed, foods high in fat and sugar are the ones turned to more frequently. This can be because these foods activate our reward pathways during a time when we’re looking to feel good, fast. Unfortunately, while eating comfort foods indeed make us feel better by potentially providing a short-lived dopamine hit, both saturated fats and refined sugars contribute to immune system activation in the gut, which end up exacerbating the problem long term.

Interestingly, both eating as an emotional response, and making unhealthy food choices as a way to self-soothe, is reported more often in women than men. To make matters worse, there are several biological differences within the brain gut axis that influence digestive vulnerabilities which, before even taking stress into consideration, render women more likely to experience GI distress. Research has shown that women perceive stress more frequently, and are more likely to have a hypersensitive gut. By turning to fat and sugar when stressed, women are adding fuel to an already vulnerable fire.

Due to the unique communication between the intestines and the female brain, food tends to move more slowly through a woman’s digestive tract. Slower digestive speed can lead to discomfort, bloating, and an increased susceptibility to the growth of “bad” bacteria. Even though in many individuals, stress is associated with a more rapid transit of food and waste through the gut, in others, stress can contribute to this slow speed, making the problem worse.

Though easier said than done, because of this, it is incumbent upon women to take extra care and promote proper gut health, by practicing mindfulness, stress reduction techniques, and healthy dietary habits so as to compensate for these biological differences, and to create an arsenal of sorts that is ready to be accessed during periods of stress. This way, when the mood-boosting benefits of cheeseburgers and chocolates are turned to, the body is ready to handle it without opening itself up to further perturbation.


Ariel Suazo-Maler holds a master’s in nutrition from Columbia University and has spent years studying the genetic and neuroanatomical underpinnings of schizophrenia, the neurophysiology of taste perception, and the role of nutrition in depression and anxiety.