In 2001, Steven Maier gave a lecture to the American Psychiatric Association about how stress can lead to some psychiatric illness. Maier said that stress triggers the same immune system/nervous system reaction as, for example, the common cold. Our immune system sends alarm signals to the brain when we are stressed. Those signals change normal nerve activity altering everything that comes after, mainly behavior, thought and mood. The study of brain-stress-immune system connection in the development of illnesses such as depression, is called “psychoneuroimmunology” which is a combination of psychology-neurology-immunology.
The body views stress as an infection triggering an immune system reaction. With high stress levels, our body releases stress hormones that increase inflammation informing your brain that you are sick. Sickness-like symptoms may include inflammation (fever/malaise), reduced food and water intake, and decreased energy and motivation. When inflammatory immune system sickness hormones are injected into brains of lab animals, the animals act like they have an infection where none exists! When the target receptors for those same stress hormones are blocked off, even if the rats were sick with an infection, there were no symptoms of being sick!
A previous article I wrote for this magazine discussed connections between the gastrointestinal system, or gut, and the brain often referred to as the “gut-brain” connection. It is in our gut that we absorb the building blocks for making, well, everything, including nerve communication chemicals like serotonin. A healthy gut “microbiome” (which means a balance of healthy probiotic organisms) impacts our ability to absorb nutrients from foods, and removing waste products, so our body can function normally. You may know about one nutrient, tryptophan, which is an essential amino acid found in protein. Once tryptophan is absorbed from the gut, it enters your blood stream, is transported to your brain where it is converted into that feel-good chemical: serotonin. That is why even minor deficiencies of essential vitamins, proteins, minerals and fatty acids greatly increase your risk of mental illnesses, like depression. If you combine deficiencies of our essential nutrients with a poorly working gut, you are very likely to develop sickness such as depression or anxiety because you will have an abnormal immune system response. The best treatments for mental health include balancing the gut microbiota with probiotics, vitamin-D levels that are high enough, omega-3 fatty acids, B-vitamins like B-12, B-6 and B-1; but, more about that the next time! In the meantime, eat healthy to have a healthy brain!