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Depression: The Brain-Gut Connection

Depression is a major mental health problem. Health Canada and the Public Agency of Canada have stated, “About 11% of men and 16% of women in Canada will experience major depression in the course of their lives.” This is significant. Depression affects all aspects of a person’s life. The greatest worry is suicide. If you are feeling suicidal, please reach out for help. Crisis Services Canada is a click away.

Did you know that 90% of your serotonin is produced in the digestive system by the microbiome? Serotonin is a neuromodulator that elevates mood and is produced in the brain and the gut. If you have a poor diet that is low in fiber, your microbiome will prevent cells in the intestine, called enterochromaffin cells, from producing serotonin.

I have wondered how serotonin made in the intestines effects brain function. I know that serotonin cannot cross the blood-brain-barrier. This barrier is a protective layer that helps protect the brain from harmful substances. So if serotonin cannot cross this barrier, how can it affect the brain?

The answer is the vagus nerve. It is the bidirectional connection between the brain and all the major organs. Serotonin in the intestines stimulates the vagus nerve. This nerve sends messages to the brain regions associated with mood. Another way that the vagus nerve can be stimulated in a positive way is through yogic breathing and movement!

Lack of serotonin is associated with depression. A class of medications called serotonin reuptake inhibitors (SSRIs) are used to increase serotonin in the brain to treat depression. One commonly prescribed SSRI is Prozac (fluoxetine).

Readers may consider changing their diet and lifestyle based on this information. You may have heard that antidepressant medication must be taken for at least a year before it can be slowly discontinued. Some people try to discontinue their medication after one year and relapse into depression. When this happens, sometimes people are told by their health care provider that they must remain on the medication for the rest of their lives! This is a depressing prospect on its own! The health care provider recommendation is true. Without improving lifestyle, the depression will remain, and the medication becomes indispensable.

The challenge in adopting a healthy eating pattern is a condition called serotonin syndrome or serotonin toxicity may occur. These two terms are used interchangeably. This happen s when the brain gets too much serotonin stimulation. This could happen if the antidepressant is combined with the positive lifestyle changes. Some of the symptoms are muscle rigidity, high fever, or confusion. People can be hospitalized with this condition.

Please work with a qualified health care provider such as a nurse practitioner, pharmacist, or a physician to help guide you with your transition from illness to health. The antidepressants need to be tapered. The whole-food, plant-based is helpful, but a hospital admission is not.

I wonder how many prescriptions for serotonin boosting medications I have dispensed because of poor diets?! Thanks for reading!! #lifestylemedicine #seniors #olderadults

Photo by Andres Ayrton from Pexels

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