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Loss of Muscle Mass

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Losing muscle mass is a normal condition when getting older, however abnormal muscle loss can be caused by malnutrition, an eating disorder, or an autoimmune disease like HIV/AIDs. Muscle deterioration can also be a sign of a serious chronic disease or mental health issue. Read below for more information on causes and how to seek treatment.

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Loss of muscle mass symptoms

Muscles are vital to everyday function, and if you noticeably lose muscle mass — especially without knowing why — it can be frightening. Losing some muscle mass is expected as you age. However, losing muscle mass rapidly, or atrophy, especially in the context of other symptoms, can indicate an underlying condition.

Common accompanying symptoms of loss of muscle mass

If you experience a loss of muscle mass, you may also experience:

8 causes of loss of muscle mass

Most people lose muscle mass as they age, which tends to happen slowly. Additionally, muscle mass can be lost if you switch to a more sedentary lifestyle. However, if muscle mass is rapidly lost, this can be a symptom of severe disease.

Lifestyle-related causes

Certain habits or aging can result in a loss of muscle mass.

  • Aging: Aging is characterized by replacement of some muscle mass with fatty tissue.
  • Sedentary lifestyle: "Use it or lose it," as some say. Use your muscles to ensure they stay strong.
  • Exercise: Exercise may lead to the strengthening of certain muscle groups at the expense of others. Running a marathon, for instance, may lead to some muscle breakdown in the unused muscles, even as the legs become stronger.

Systemic causes

Systemic causes of a loss of muscle mass are related to disease or illness.

  • Cancer: Advanced cancers use a lot of energy and may break down muscle as a source of body fuel. Also called cancer wasting or cancer cachexia, this is characterized by a progressive loss of not only muscle but also body fat and overall weight. This phenomenon accounts for 20-30% of cancer deaths.
  • Chronic disease: Advanced diseases of the lungs, heart, or kidneys can lead to loss of muscle mass.
  • Neurologic deficits: Altered cognition and movement difficulties associated with the neurologic disease can lead to malnutrition and weight loss.
  • Medication side effects: Some medications may cause loss of muscle mass.
  • Genetic: Rare genetic diseases can result in loss of muscle mass.

Metabolic causes

A loss of muscle mass related to metabolic processes include the following.

  • Malnutrition: Extremely poor diet can lead to loss of muscle mass as your body breaks down the muscles for energy.
  • Endocrine disease: Imbalance of various hormones caused by damage to hormone-producing glands can lead to unintentional weight loss. Examples include diabetes or an over-active thyroid (hyperthyroidism).

Inflammatory causes

Inflammatory causes of a loss of muscle mass include the following.

  • Autoimmune disease: Autoimmune disease, when your immune system becomes confused and attacks your own tissues, can lead to weight loss due to the associated high energy use.
  • Infectious disease: Chronic infection can cause weight loss and loss of muscle mass as your body breaks down tissues for energy.

Gastrointestinal causes

Gastrointestinal causes of a loss of muscle mass may include the following.

  • Malabsorption: Some diseases of your gastrointestinal tract make it less efficient at absorbing nutrients, leading to loss of muscle mass.
  • Inflammatory: Inflammation of your stomach or intestines can cause poor nutrient uptake.

Psychiatric causes

Psychiatric causes relate to your feelings, emotions, behaviors, and cognitive processes.

  • Mood disorder: Certain mood disorders, especially depression, can lead to a loss of appetite.
  • Eating disorder: People may lose muscle mass if they have an eating disorder that alters their nutritional intake.
  • Drug use: Overuse of certain substances can lead to weight loss and loss of muscle mass. Examples include methamphetamines ("meth").

This list does not constitute medical advice and may not accurately represent what you have.

Overactive thyroid

Overactive thyroid, or hyperthyroidism, means that the thyroid gland in the neck produces an excess of the hormone thyroxine and causes a metabolic imbalance.

Hyperthyroidism can be caused by autoimmune disorders such as Graves' disease; by benign growths in the thyroid; or by inflammation of the gland, called thyroiditis.

The condition may run in families. Women seem to be more commonly affected than men.

Hyperthyroidism causes very high metabolism with sudden and unexplained weight loss, rapid and irregular heartbeat, sweating, nervousness, and anxiety.

Goiter, or swelling of the thyroid gland, may appear at the base of the neck. The eyeballs can protrude and become irritated, a condition called Graves' ophthalmopathy.

If not treated, hyperthyroidism can lead to serious heart rhythm abnormalities and osteoporosis. An endocrinologist can diagnose the condition through a physical examination and simple blood test.

Treatment is done with anti-thyroid medications and sometimes radioactive iodine. Surgery to remove part of the thyroid gland may be done. The condition usually responds well to treatment and monitoring, and to improved diet, exercise, and stress reduction.

Mitochondrial myopathy

Mitochondrial myopathy includes a group of inherited genetic disorders that affect the muscles of the body.

Make an appointment with a physician to further analyze what genetic defects may be present, and begin prescription treatment.

Idiopathic inflammatory myopathy

Idiopathic inflammatory myopathy refers to a closely related group of conditions that cause inflammation of muscle tissue.

Make an appointment with a physician to determine exactly what subtype of inflammatory myopathy you are experiencing. The physician will most likely prescribe a oral steroid to reduce inflammation and put in an IV to protect the kidneys.

Rarity: Ultra rare

Top Symptoms: fatigue, muscle aches, fever, rash, unintentional weight loss

Urgency: Primary care doctor


HIV (human immunodeficiency virus) refers to a virus that kills or damages the body's immune system cells and spreads through unprotected sex with an infected person, sharing drug needles or through contact with the blood of an infected person. AIDS (acquired immunodeficiency syndrome) occurs when the body's immune system has become very weak and has a difficult time fighting off other infections.

You should visit your primary care physician to confirm the diagnosis and discuss treatment options. Antiretroviral drugs work very well and are recommended in order to reduce risk of progression and prevent transmission of HIV.

Rarity: Rare

Top Symptoms: fatigue, headache, cough, fever, distal numbness

Urgency: Primary care doctor

Cushing syndrome

Cushing syndrome is a hormonal disorder that occurs when there is too much of the stress hormone cortisol in the body. It can be caused by taking steroid medications commonly prescribed for asthma or arthritis, or by problems with the glands in the body that are involved in creating cortisol. Symptoms can vary from person to person but often include easy bruising, a "hump" on the back, and stretch marks. Fatigue, large stomach, red round face, and high blood sugar may also occur.

You should consider visiting a medical professional in the next week or two to discuss your symptoms. Cushing syndrome can be evaluated with a review of your symptoms and medical history, as well as blood tests. Treatment depends on the cause of your condition. If caused by steroid medication, you may be instructed to lower the dosage slowly over time. If caused by issues with your glands, surgery, radiation, or medication may be an option.

Rarity: Rare

Top Symptoms: fatigue, headache, depressed mood, weight gain, back pain

Urgency: Primary care doctor


Anorexia nervosa is a condition characterized by preoccupation with weight loss and intense fear of gaining weight. This leads to caloric restriction and weight loss. In its most severe form, this can even be life-threatening.

Patients with anorexia nervosa should see a primary care physician who will coordinate care with a psychologist, counselor, or other mental health professional.

Amyotrophic lateral sclerosis (ALS)

Amyotrophic lateral sclerosis is also called ALS or Lou Gehrig's Disease. It is a degenerative disease that destroys nerve cells, which eventually leads to loss of control over muscle function.

The cause of ALS is not known. It may be inherited and/or due to a chemical imbalance, faulty autoimmune response, or exposure to toxic environmental agents.

Symptoms include weakness; difficulty with speaking, swallowing, walking, or using the hands; and muscle cramps. The muscles of the arms, hands, legs, and feet are most involved at first. It does not affect the senses or a person's mental ability.

ALS is progressive, meaning it worsens over time. There is no cure, but supportive care can keep the patient comfortable and improve quality of life.

Diagnosis is made through several tests including blood tests; urine tests; MRI; electromyography (EMG) to measure muscle activity; nerve conduction studies; and sometimes muscle biopsy or spinal tap (lumbar puncture.)

Treatment involves medications to both slow the progression of the disease and ease the symptoms; respiratory therapy; physical therapy; occupational therapy; and psychological support.

Loss of muscle mass treatments and relief

Most of the time, when people lose muscle mass, it is due to a change to a more sedentary lifestyle or aging. Loss of muscle mass or significant weight loss in other contexts, however, can indicate a condition that merits full medical evaluation. Unfortunately, in this case, muscle loss is harder to combat. If you have rapidly and unintentionally lost weight and muscle mass, see a physician.

At-home treatments

You can try the following treatments at home to address your symptoms.

  • Exercise: The most effective way to build your muscles is to use them. Go on a run, hit up the gym, or be more active around your home.
  • Diet alteration: You can lose muscle mass if you don't eat enough, as your body will break down muscle for energy.

When to see a doctor

If at-home treatments are not enough, you can consult your physician about the following. Once you learn more about the cause of your loss of muscle mass, you can determine the best treatment plan together.

  • Blood and urine testing: Lab tests can check your nutrition and other metrics.
  • Imaging: X-rays or other imaging can figure out the cause of your loss of muscle mass symptoms.
  • Muscle testing: Strength and testing of the nerves feeding muscles can help with diagnosis.
  • Physical or occupational therapy: In some cases, therapies can help build strength or function.
  • Medication: Some medical conditions that cause muscle loss require medication.
  • Surgery: Rarely, loss of muscle mass may be caused by a disease requiring an operation.

When it is an emergency

You should seek help without delay if you have:

  • Fever, chills, or signs of infection
  • Difficulty breathing
  • Any new bumps or masses
  • Sudden-onset confusion
  • Frequent falls or imbalance


Preventing a loss of muscle mass can be achieved by exercising regularly (such as strength training) in conjunction with a balanced diet of lean meats and proteins, fruits and vegetables, healthy fats, and whole grains. Of course, if this loss is due to an underlying illness, this must also be addressed and mindfully managed.

Questions your doctor may ask about loss of muscle mass

  • Have you ever been diagnosed with diabetes?
  • Did you just suffer from a high impact injury (e.g., a fall, collision, accident or sports trauma)?
  • Did your symptoms start after getting sick?
  • Have you ever been diagnosed with cancer?

Self-diagnose with our free Buoy Assistant if you answer yes on any of these questions.

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The stories shared below are not written by Buoy employees. Buoy does not endorse any of the information in these stories. Whenever you have questions or concerns about a medical condition, you should always contact your doctor or a healthcare provider.
Dr. Rothschild has been a faculty member at Brigham and Women’s Hospital where he is an Associate Professor of Medicine at Harvard Medical School. He currently practices as a hospitalist at Newton Wellesley Hospital. In 1978, Dr. Rothschild received his MD at the Medical College of Wisconsin and trained in internal medicine followed by a fellowship in critical care medicine. He also received an MP...
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  1. Siparsky PN, Kirkendall DT, Garrett WE. Muscle changes in aging: Understanding sarcopenia. Sports Health. 2014;6(1):36-40. NCBI Link
  2. Jasmin L. Muscle atrophy. U.S. National Library of Medicine: MedlinePlus. Updated December 6, 2018. MedlinePlus Link
  3. Campins L, Camps M, Riera A, Pleguezuelos E, Yebenes JC, Serra-Prat M. Oral drugs related with muscle wasting and sarcopenia. A review. Pharmacology. 2017;99(1-2):1-8. NCBI Link
  4. Kalyani RR, Corriere M, Ferrucci L. Age-related and disease-related muscle loss: The effect of diabetes, obesity, and other diseases. Lancet Diabetes Endocrinol. 2014;2(10):819-829. NCBI Link
  5. Wendelsdorf K. The mechanism of muscle loss in cancer. National Institutes of Health. Published November 4, 2013. NIH Link
  6. Minetto MA, Ghigo E. Sarcopenia in endocrine disorders - the iceberg or its tip?. Eur Endocrinol. 2015;11(1):41-42. NCBI Link
  7. Inflammatory myopathies fact sheet. National Institute of Neurological Disorders and Stroke. Updated July 6, 2018. NINDS Link
  8. Powers SK, Lynch GS, Murphy KT, Reid MB, Zijdewind I. Disease-induced skeletal muscle atrophy and fatigue. Med Sci Sports Exerc. 2016;48(11):2307-2319. NCBI Link