After the death of Caroline Rustigian’s mother earlier this year, her physical health took a tumble. “I stopped eating and couldn’t keep food down,” says Rustigian, a public relations consultant and podcaster in Laguna Beach, Calif.
Desperate to feel better, Rustigian went to urgent care, where she was told that acid reflux was one cause of her tummy troubles. The doctor recommended medication, which eased her discomfort. However, the mother of two still didn’t feel like her old energetic self. “I was fatigued and just trying to get through each day,” she recalls.
Finally, Rustigian met with her naturopathic doctor, who said grief was the culprit. “My doctor said emotional stress and not eating threw off the healthy bacteria in my stomach, which compromised my microbiome.” A veritable universe living within us, the microbiome has been garnering attention from scientists and the medical community for its impacts on human health.
“The microbiome is made up of trillions of microbes, including bacteria, yeast, and viruses,” says Thalia Hale, a naturopathic practitioner in Palo Alto, Calif. These tiny organisms reside in our gut and on our skin. Like a hard drive that keeps a computer running, this network helps the body synthesize and process key nutrients like thiamine, a B vitamin made by intestinal bacteria that fuels brain function.
A possible link
According to Hale, grief can throw the body off course, upsetting the gastrointestinal tract. For starters, stress can activate the sympathetic nervous system, more commonly known as the fight-or-flight response. In this survival state, “heart rate and blood pressure rise, as do levels of the hormone cortisol,” Hale adds. And when the body is warding off danger, it’s not focused on digestion or eating. Rustigian says that after her mother died, she didn’t eat for days. And research has found that dietary changes can shift the microbiome in a matter of days.
While it’s well known that heartache can make the belly ache, research examining the connection between bereavement stress and gut health is limited. However, one 2020 paper published in the journal Frontiers in Psychiatry suggests that “gut microbiota may play a role in influencing health outcomes following bereavement” because chronic and ongoing stress can disrupt the microbiome.
It’s challenging to solely examine bereavement, because grief includes other emotions such as anger, sadness, and denial. When these feelings linger, they can contribute to mental health concerns like anxiety and depression. These conditions’ ebbs and flows have been linked to the bacteria residing in the gut.
What science tells us
The connection between our brain and our gut, including the microbiota that thrive there, was surprising when it was first discovered more than 10 years ago. Thus far, most of the relevant research has focused on animals, according to Karina Alviña, a neuroscientist at the University of Florida whose lab uses mice to investigate how gut flora influence brain function. “In an animal model, you can [use antibiotics to] deplete nearly all of the gut microbiome and feed the mice with a particular formulation [of bacteria],” she says, which allows scientists to directly test the effects of a single bacterial species or a combination.
In humans, the picture is murkier. But a team of scientists in Belgium was among the first to tie the characteristics of an individual’s gut microbiome to measures such as overall happiness and depression in a large-scale population study published in 2019. “People who report low quality of life tend to have disturbed gut microbiomes—and there was a notable loss of certain bacteria that was very specifically associated to this loss of well-being,” says Jeroen Raes, a bioinformatician and senior author of the study.
Mental health and the gut-brain axis
Losing a loved one is by far one of the most stressful life events. “My mom was my best friend,” Rustigian says. “When she died, I lost my true advocate, and I felt numb.” This emotionally low period can result in the loss of sleep and appetite, as well as loneliness. And the ongoing stress may affect what scientists call the gut-brain axis.
Barely a decade ago, the brain was thought to be completely isolated from the rest of the body. So for Alviña, “the biggest mindset change” was the realization that the brain not only instructs the body to move and breathe, but that signals from the gut as well as other organs and tissues can also alter how the brain functions.
How the mechanism behind this bidirectional communication works is an open question, but several possible explanations have emerged. In the Belgian study, people with depression had fewer gut bacteria that produced butyrate, a fatty acid essential to intestinal health, with anti-inflammatory properties. The resulting inflammation in the gut due to the lack of these butyrate producers is “linked to the neuro-inflammation we often see in the context of depression,” Raes says.
More directly, gut bacteria produce molecules such as dopamine and serotonin, which play vital roles in neural signaling. Low levels of these neurotransmitters can cause depression and neurological diseases like Parkinson’s.
These neurotransmitters might interact with the nerve endings of the vagus nerve—which is responsible for involuntary movements such as breathing and digestion, and connects the brain to most of the body’s organs, including the gut. Experiments on mice bolster this view. For animals where the vagus nerve was cut, microbiome-mediated effects on their behavior disappeared.
Probiotics: help or hype?
Given the tantalizing evidence, an obvious next step would be to supply the gut with beneficial probiotics. Raes, however, stresses that research on the gut microbiome and its impact on grief and mental health is still in its infancy. And while “the potential for probiotic intervention is exciting, there’s not [currently] enough evidence to advise people with depression to take them,” Raes says.
Dr. Ripal Shah, an integrative medicine specialist and psychiatrist at the Stanford University School of Medicine, agrees that the jury’s out on which bacterial species will prove most helpful to people. But at the same time, gut health and tweaking gut flora are frequent topics in the weekly integrative mental health group she leads with a colleague.
Overall, grief is a full-body experience, and Hale says that both stress-management and dietary practices can aid in recovery.
Read More: What We Know About Leaky Gut Syndrome
Research suggests that diet plays a significant role in determining which gut bacteria continue to thrive. And eating foods naturally imbued with probiotics like fermented products and yogurt is one easy way to help restore gut health, says Shah. “But because we don’t know exactly which species are helpful—and how much—it’s actually useful to think [of the goal] as increasing the diversity of your gut flora.”
Switch up the cuisine, Shah advises. If you’re having kimchi one week, kombucha the next week, and kefir the following week, you’re exposed to a wider range of active cultures than if you’re just grabbing the same brand of kimchi every time.
Just one episode of depression or anxiety can create a feedback loop, priming us for recurrences. “One of the pathologies of depression and anxiety might be that they contribute to the ratio [of gut flora] going out of whack,” Shah says. “And then ongoing stress continues to skew or worsen that ratio.” Because of this, Shah says it’s crucial to find ways to de-stress.
On the flip side, Shah says, “the potential of positive mood to influence the microbiome is actually reassuring” because it means gut health may be able to be manipulated with mental-health interventions.
During periods of immense mourning, stress management might seem like putting a bandage on a gaping wound. However, Hale says these tools can help the nervous system switch gears, putting the parasympathetic nervous system (which helps calm us down) back in the driver’s seat.
One easy exercise is called “square breathing” or “box breathing.” Simply take a breath in and hold for four counts, exhale for four counts, and repeat four times. Used by Navy Seals in high-stress situations, this breathing technique helps calm the autonomic nervous system, which restores relaxation.
A 2017 study in the journal Frontiers in Immunology found that exercises such as yoga and tai chi may help reverse the effects of stress on the body. The researchers state that these mind-body interventions “reversed genes involved in stress-induced inflammatory reactions.”
Shah also suggests acupuncture for her patients, which has been demonstrated to relieve stress in numerous studies, and to engage in at least 30 minutes a day of moderate-intensity exercise.
Lastly, “any sort of vitamin and mineral deficiency can be worsened or caused by stress,” Shah notes. So addressing these deficiencies—primarily through diet rather than supplements—is of tantamount importance. Similarly, avoid consuming foods that promote inflammation, such as refined sugar, fried foods, or foods that you’re allergic to.
One way to cope with bereavement is to embrace additional support. “We’re not meant to grieve alone,” says Abigail Levinson Marks, a clinical psychologist in San Francisco who specializes in grief. “In nearly all cultures, the way we deal with loss is collective, because community helps us heal,” she adds.
Grief support groups and online forums can be therapeutic, because they give you a chance to meet and befriend fellow mourners. Marks adds that seeing your experience reflected in someone else’s story can help you feel less alone.
Since each person’s path differs, group support might not be right for everyone. If that’s the case, speaking with a counselor can also help. Not only will your therapist listen and empathize, but expressing your thoughts and feelings may have a positive effect on your physical health too. For instance, one 2022 paper in the journal Dialogues in Clinical Neuroscience reiterates that holding in our emotions may lead to low-level stress, hindering the body’s immune response.
In addition to therapy and group support, give yourself permission to say yes when loved ones offer help. For example, friends might take on your household chores or run errands, or your employer may provide bereavement leave. “Anything that lightens your load can give you more time for self-care,” Hale says.
In our rush-to-recovery culture, we may judge ourselves when suffering lingers. But keep in mind that healing is a journey, not a sprint. So even if your loss was months ago or before the pandemic began, self-care, support, and healthy eating can still be beneficial. Hale also reiterates that self-compassion is vital.
In the end, Caroline Rustigian found that an antidepressant, probiotics, exercise, and therapy helped to ease her grief—and her gut issues. “It took a while to figure out what was going on,” she says. “But once I started a combination of therapies, my stomach troubles disappeared, and I got better.”