How Major Depression Affects the Brain and Body – Why Residential Treatment Can Help

Major depression, or major depressive disorder, is a mood disorder and mental illness that causes significantly and persistently low moods. More than just feeling down for a day or two, depression causes a bad mood that you can’t shake for weeks. Some of the key symptoms and signs of depression are:

• Persistent feelings of sadness and hopelessness
• Loss of interest in activities you normally enjoy
• Difficulty sleeping or sleeping too much
• Weight gain or weight loss
• Extreme fatigue
• Anxiety, restlessness, frustration, or irritability
• Feeling worthless, guilty, or ashamed
• Difficulty concentrating, making decisions, or remembering
• Thoughts of suicide and death

You may be diagnosed with depression if you have some of these symptoms for a couple weeks or longer, if they are severe enough to disrupt your normal functioning, and if they cannot be explained by substance abuse, medications, or an illness.

No one knows for sure what causes depression, but researchers have determined that it is definitely a disorder that has biological underpinnings and that the chemistry of the brain plays a big role. Studies have uncovered how differences in the brain’s structure and chemicals may contribute to depression, but also ways that having depression changes your brain:

• Cortisol and memory. Part of the brain called the hippocampus releases the hormone cortisol when you’re stressed, which includes episodes of depression. When your brain gets flooded with cortisol for long periods of time, it can slow or stop the growth of new neurons in the hippocampus. This results in the hippocampus actually shrinking in size, which in turn leads to memory problems.
• Cortisol and the amygdala. The influx of cortisol triggered by depression also causes the amygdala to enlarge. This is a part of the brain associated with emotional responses. When it becomes larger and more active, it causes sleep disturbances, changes in activity levels, and changes in other hormones.
• Brain inflammation. It isn’t yet clear whether inflammation is a trigger for depression or depression causes inflammation. But, studies clearly show a link, that people with depression have more inflammation in the brain. One study specifically found that people who have struggled with depression for more than ten years have 30 percent more inflammation. Brain inflammation can worsen depression, interfere with neurotransmitters that regulate mood, and negatively impact learning and memory.
• Hypoxia. Hypoxia, or reduced oxygen, has also been linked with depression. The result of the brain not getting adequate amounts of oxygen can include inflammation and injury to and death of brain cells. In turn, these changes in the brain impact learning, memory, and mood.

Depression is much more than just a brain disorder. It causes physical symptoms and can cause lasting damage to the body because of both direct effects and indirect complications of living with this mental illness. For instance, depression can change your appetite. It may trigger you to eat less and lose an unhealthy amount of weight. Or it can cause you to eat more, leading to weight gain and associated health conditions.

You may also experience chronic pain as a result of depression. Unexplained aches and pains, like headaches, back pain, or joint tenderness, can be triggered by depression. Although not fully understood, it may be that depression makes you less tolerant of pain, so that everything just hurts more.

Living with depression puts you at risk for serious physical health conditions, including heart disease and stroke. The reason for this may be that depression triggers an overproduction of clotting factors and variation in heart rate. These are both factors that can lead to a heart attack or stroke.

Gastrointestinal distress is a potential complication of depression. The gut actually has a major connection to mood and mental health and is sometimes referred to as the body’s second brain. There are important receptors in the gut and an ecosystem of bacteria, which when out of whack can affect mood. If you are depressed, you may experience stomach aches, indigestion, nausea, cramps, or bloating.

Fatigue is a common symptom of depression, and one of the most consistent physical consequences of this mental illness. This lack of energy is beyond normal tiredness. It makes you feel apathetic, irritable, and like you just don’t want to do anything. Just getting out of bed in the morning can feel insurmountable.