Major depressive disorder (MDD) is a type of depressive disorder that affects more than 15 million adults in the United States and is the leading cause of disability in the U.S. for individuals 15-44 years of age. Depression can result in extreme unhappiness in every aspect of an individual’s life resulting in potential turmoil in the workplace, in the home and in personal relationships with others. According to the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM V), at least five of the following symptoms must be present within a two-week period with at least one of the symptoms being depressed mood. Additionally, these symptoms must cause apparent distress in social and occupational functioning.

  • Sleep disturbance
  • Loss of interest in activities
  • Feelings of guilt
  • Loss of energy
  • Difficulty concentrating
  • Change in appetite
  • Psychomotor agitation
  • Sadness
  • Suicide ideations

Depression, like all other mental health disorders may be difficult to diagnose because there is no laboratory test, biopsy or imaging test to confirm your suspicion. Rather, mood disorders and other mental health disorders are diagnosed strictly based on symptom criteria. Medical illnesses that mimic depression? Below are medical illnesses that are known to resemble depression and these conditions can be ruled out with laboratory tests. It may not hurt to ask your doctor about these disorders if you are being evaluated for depression.


Hypothyroidism is an endocrine disorder causing a low metabolism due to suppression of hormones released from the thyroid gland. Individuals often present with the following symptoms:

  • Extreme fatigue
  • Weight gain
  • Decreased appetite
  • Muscle aches
  • Impaired memory
  • Emotional lability
  • Dry skin
  • Cold intolerance
  • Hair loss

Iodine deficiency remains one of the most common causes for hypothyroidism in the United States and worldwide. Approximately 4% of the U.S. is diagnosed with hypothyroidism and the diagnosis is confirmed through laboratory tests, specifically TSH, and T4 levels.


Hypercalcemia results from an increased level of calcium in the blood. 90% of cases of hypercalcemia are caused by malignancy or hyperparathyroidism and the severity of symptoms depend not only on the level of calcium in the blood but how fast this level has increased over time. The common mnemonic used to describe the symptoms related to hypercalcemia is Stones, Bones, Groans and Psychiatric overtones. The following are specific signs and symptoms resulting from hypercalcemia.

  • Kidneys (Stones)
    • Polyuria (excessive urine)
    • Nocturia (urinating at night)
    • Dehydration
    • Renal Stones
    • Renal Failure
  • Bones
    • Bone Pain
    • Fractures
    • Height Loss
    • Bowed Shoulders
  • Gastrointestinal (Groans)
    • Constipation
    • Nausea
    • Anorexia
    • Pancreatitis
    • Gastric Ulcer
  • Psychiatric (Overtones)
    • Lethargy
    • Weakness
    • Confusion
    • Coma

Hypercalcemia can be diagnosed by a blood test by measuring parathyroid hormone (PTH), calcium, vitamin D and parathyroid hormone-related peptide (PTHrP). It is extremely important to diagnose the underlying reason for this hypercalcemia.

Vitamin D Deficiency

Vitamin D deficiency results from inadequate exposure to sunlight, malabsorption and in breast fed only infants who are not given vitamin D supplements. In children, vitamin D deficiency presents with severe bone pain and muscle aches creating problems walking and with movement. Adults often present with bone pain, fatigue and low mood. Some studies have shown a direct link between vitamin D deficiency and depression in adults. Vitamin D is diagnosed by measuring 25(OH) D levels in the blood.

Chronic Fatigue Syndrome (CFS)/Systemic Exertion Intolerance Disease (SEID)

Chronic fatigue syndrome (CES) is a state of chronic exhaustion and cognitive difficulties that occurs for at least six months in duration and is not associated with any other known medical conditions. This is usually a diagnosis of exclusion, as other medical illnesses should be ruled out. The signs and symptoms are clinically similar to depression and often times these disorders can be mistaken for one another. The following are signs and symptoms associated with chronic fatigue syndrome:

  • Severe problems with short-term memory or concentration
  • Sore throat
  • Tender lymph nodes
  • Postexertional malaise lasting more than 24 hours
  • Multiple joint pain without swelling or redness
  • Headaches of a new type, pattern or severity
  • Unrefreshing sleep
  • Muscle pain


Type 2 diabetes results from a broken pancreas that is no longer able to make enough insulin to lower the body’s sugar. Type 2 diabetes is often called insulin-resistance diabetes meaning that the body does not respond adequately to insulin and an elevation in blood sugar will occur. Many individuals present to their doctor feeling tired, irritable and complaining of changes in weight to only find themselves having new-onset type 2 diabetes. Once diagnosed, individuals are usually given insulin or oral medications to lower their blood sugar. Low blood sugar can also result in low energy and irritable mood resulting in symptoms that mimic depression. Blood sugar testing, diet, exercise, insulin and medication regimens are the complication associated with diabetes can become so stressful, many individuals become burned out and frustrated. Additionally, studies have shown that caring for diabetes can be such a burden that a term “diabetes distress” is now recognized by experts as the worry, stress and concern associated with caring for diabetes. Medical illnesses that mimic depression? You might be experiencing diabetes.

Introducing Everyday Coping Skills into Your Life

Coping skills do not have to be these unattainable, lofty ideas but rather they can be concrete everyday activities such as hobbies. Hobbies can also be a way to form bonds between other individuals who share the same interests thereby being a way of social support. Hobbies can be anything of interest that occupies and fascinates an individual. They can include outdoor fitness activities, traveling, learning a new language, enrolling in a cooking class, learning to knit or any other activity that allows the individual to adopt a happy mindset.

We’re Here for You

If you think you or someone you love might be experiencing a medical illnesses that mimic depression, contact us today. Center for Discovery’s treatment centers specialize in treatment for eating disorders, mental health and dual diagnosis treatment with unique treatment programs for every individual to get them on their way to eating disorder recovery.

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