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Major depressive disorder (MDD) can cause more than depression.  It can lead to complications that affect your health and change how you think and behave.

Weight Gain and Obesity

When you’re depressed, it’s no surprise you turn to food for comfort. (Some call this practice emotional eating.)  

MDD can also scramble your appetite hormones, so you eat a lot more than normal. Some antidepressants even make you put on pounds. In fact, weight gain is one of the main reasons people stop taking their depression meds.

Ask your doctor to refer you to a dietitian who understands and works with MDD.

Chronic Illness

People who have MDD often have one or more long-term diseases, such as:

  • Cancer
  • Multiple sclerosis
  • Heart disease
  • Diabetes  

Though many of these conditions don't have cures, you can manage them. But depression makes them harder to treat and control. This may partly explain why men and women who have MDD die sooner than people who aren’t depressed.

Lifestyle factors like lack of exercise, an unhealthy diet, and alcohol misuse may also contribute to poor health and early death.

Chronic Pain

There’s a strong link between physical pain and depression. They share some of the same neurotransmitters -- brain chemicals that act as messengers between nerves. They also share some of the same nerve pathways in your brain and spinal cord.

So depression can make you more sensitive to pain, and chronic pain can fuel depression. Because the two have so many links, doctors often treat them together, sometimes with the same meds. For example, a type of antidepressant called a serotonin norepinephrine reuptake inhibitor (SNRI) may also work for nerve pain and anxiety.


To manage difficult feelings, you might try to cut or burn your skin, pull out hair, or pick at scabs. Doing drugs or drinking at the same time makes serious injury more likely.

Self-harm is more common in teens and tweens, but it can also happen later in life. If you’re struggling with it, talk to your doctor or a trusted friend or family member. It takes more than willpower to quit. 

You might have suicidal thoughts during severe MDD flares. These go away when you get treatment. If you ever think about ending your life, call your doctor, a local crisis center, or the National Suicide Prevention Lifeline.

Substance Misuse

About one-third of people with MDD have a problem with alcohol or drugs. Both can change how your mind and body work.

When you use substances the wrong way, you’re more likely to get other mental health disorders, like anxiety. And if you have thoughts of suicide, there’s a greater chance you’ll act on them.  

Cognitive Changes

MDD can change the way your brain works. You might have trouble focusing or remembering a word or someone’s name. This can happen during or between bouts of severe depression. And it can make it harder to function in all areas of your life -- work, school, and personal relationships.  

Antidepressants may not improve cognitive symptoms, and they might not get better when depression lifts. Other types of treatments may help, though. Cognitive remediation therapy (CRT) teaches you how to overcome brain-related challenges. Common talk therapies, including cognitive behavioral therapy (CBT) and mindfulness therapy, can work well, too.

Show Sources

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Psychiatry Research: “Weight gain in Major Depressive Disorder: Linking appetite and disordered eating to leptin and ghrelin.”

Nutrients: “Meeting of Minds around Food Addiction: Insights from Addiction Medicine, Nutrition, Psychology, and Neurosciences.”

Psychology Today: “Why Choose Between Depression or Weight Gain?”

Psychosomatic Medicine: “Major Depressive Disorder in Medical Illness: A Review of Assessment, Prevalence, and Treatment Options.”

European Psychiatry: “Associations of major depressive disorder with chronic physical conditions, obesity and medication use: Results from the PISMA-ep study.”

CMAJ: “Depression and mortality in a longitudinal study: 1952-2011.”

Psychiatry Investigation: “Pain and Depression: A Neurobiological Perspective of Their Relationship.”

Current Opinion in Psychiatry: “Major depression and comorbid substance use disorders.”

The Canadian Journal of Psychiatry: “Suicidal Behavior in Mood Disorders -- Who, When, and Why?”

BMC Psychiatry: “Clinical guidelines for the management of depression with specific comorbid psychiatric conditions: French recommendations from experts (the French Association for Biological Psychiatry and Neuropsychopharmacology and the fondation FondaMental).”

National Alliance on Mental Illness (NAMI): “Self-Harm.”

Cambridge University Press: “Cognitive impairment in major depressive disorder.”