When you think of depression, you probably think of it as a mental illness, but the truth is some of the most devastating effects of depression are physical. On the other hand, you may have experienced years of physical symptoms and never considered depression as a possible cause.
We still don’t know exactly what causes depression. There’s strong evidence it’s related to neurotransmitters, the chemical messengers of the brain, but this isn’t the whole picture. Certain genes can predispose a person to low mood, and stress levels are another important factor. The brain and body are complex and intertwined; there is nothing that affects the brain that doesn’t affect the body and vice versa.
Either way, it’s important to be aware of the physical symptoms of depression, so you can get proper treatment and start down the path of feeling better—mind, body, and spirit.
Researchers have found links between depression and headaches. These headaches are usually described as mild to moderate in intensity and are probably tension-related. One study found that people with depression were quicker to develop a headache under induced stress, than those without depression. Even if a person isn’t formally diagnosed with depression, tension headaches are often treated with antidepressant medications, which demonstrates how the two are biologically interrelated.
Stomachaches are common in people with depression. People with depression report nausea, diarrhea, and constipation, sometimes leading to a loss in appetite. Similar to headaches, stress and the subsequent changes in the nervous system is the probable cause. Additionally, stomachaches can also be a side-effect of eating different types of foods or a change in exercise habits.
Insomnia or hypersomnia
Almost everyone with depression has some type of sleep disturbance—either sleeping too much or too little. When you are not sleeping properly, your body is not able to enter into the rest and recovery phase of deep sleep. During our most restful sleep, the body goes to work repairing cells and tissues. When you are not getting good sleep, it can have a lasting impact on your physical health.
Fatigue is different from the lack of motivation typically associated with depression—it’s feeling completely drained and void of all energy. Some people describe it as feeling like there are heavy weights attached to their body, pulling them down. This can come from chronic sleep issues or can simply be a classic symptom of depression. People with fatigue struggle to get out of bed, get off the couch, or do normal day-to-day activities. This has a domino effect on jobs and relationships, compounding the effects of depression.
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Weight loss or gain frequently happens with depression. One major cause is the side-effects of antidepressant medications. A noticeable change in appearance can be a blow to a person’s self-esteem and is especially difficult for those already dealing with depression.
Lowered immune function
When the nervous system is dysregulated, like what happens with depression, it has a huge impact on the immune system. This means more colds, infections, and viruses—all of which affect quality of life. We now know that lowered immunity over time can be linked back to chronic illnesses, which is discussed in the next section.
The co-occurrence of depression and chronic illnesses, such as autoimmune disorders, Parkinson’s, and heart disease, is significant. This begs the question, does depression cause chronic illness? Or, does chronic illness cause depression? In an article published by the Harvard Medical School, it says, “medical illnesses or medications may be at the root of up to 10% to 15% of all depressions.” So, that provides some insight on chronic illness causing depression, but what about the other way around? The fact is that we know that people with depression have a higher risk of developing chronic diseases, but we don’t know exactly why. How long-term stress affects the body is an area of emerging research.
It’s essential for medical professionals and therapists to be aware of the overlap between chronic illness and depression and treat both conditions accordingly. All too often, depression in people with chronic illness goes undiagnosed and untreated.
Much like chronic illness, chronic pain can turn into an endless loop with depression—people with pain become depressed, and people with depression develop pain. No matter which comes first, they exacerbate each other and prevent either one from improving. Back pain is especially common with depression and can become debilitating.
What the physical symptoms of depression teach us is that self-care is crucial. People with depression often take medication or go to talk therapy, but they may not prioritize sleep or eating nutrient-dense food. Considering these symptoms can be the most debilitating, it’s vital to make coping with the physical manifestations of depression part of your comprehensive treatment plan.
But it’s not all bad news. We know that depression can be treated, and when thought patterns improve, many of the physical symptoms improve as well. Every day, we’re learning more and more about the nervous system and how it impacts the mind and body. Body-centered approaches, like somatic psychotherapy, are rising to the forefront of treatment, and they focus more on the root causes of depression and have lasting positive results for clients.
Kerry J. Heckman is a freelance writer and therapist based in Seattle. She authors a wellness & lifestyle blog called Words Heal and writes about health, chronic illness, and travel. You can also follow her healing journey on Twitter and Instagram.