Suprising Dangers of Unintended Weight Loss

Date: December 1, 2016      Publication: Bottom Line Health      Source:  Robert Wergin, MD, University of Nebraska Medical Center      Print:

It can be a red flag for a number of serious health conditions…

If you start losing weight without even trying, it may at first seem like a dream come true. But if the number keeps on dipping, your excitement should turn to worry.

Unintentional weight loss is when you lose weight (5% or more of your normal weight within six to 12 months) without dieting or increasing physical activity. It may occur following a loss of appetite or when you’re consuming the same number of calories as usual. In either case, it is often a warning signal that something serious is going on with your health. While older adults are at greater risk for unexplained weight loss—it occurs in 15% to 20% of adults age 65 and older—people who are in their 50s or even younger can also be affected.

A thorough checkup is critical to determine the cause of unintentional weight loss. I recommend starting with your primary care physician or family doctor, who will take a detailed history and order blood work and urine tests based on other symptoms. Armed with the results, he/she can direct you to an appropriate specialist if necessary.


Many people know that cancer can cause unintentional weight loss (more on this below), but there are other underlying causes as well…

GI Disorders

If you have diarrhea, abdominal pain, bloating and/or gas in addition to unintentional weight loss, you could have a gastrointestinal (GI) disorder, such as celiac disease or inflammatory bowel disease (IBD). The facts you need…

Celiac disease is a genetic autoimmune disorder affecting one in 100 people. When an affected individual consumes gluten (a protein found in wheat, rye and barley), the immune system launches a response that attacks the lining of the small intestine.

This can trigger a number of unpleasant GI symptoms, such as pain, bloating and diarrhea, all of which can lead to weight loss. Repeated exposures to gluten eventually damage the intestine enough to compromise nutrient absorption, further contributing to weight loss.

A simple blood test done by a primary care physician can screen for celiac disease, but the diagnosis is confirmed by a small bowel biopsy done by a gastroenterologist. There’s no cure, but adhering to a strict gluten-free diet should bring relief and halt excessive weight loss.


Caution: There are many foods you would be surprised to learn contain gluten—these can include soups, potato chips, granola bars, rice mixes and salad dressings. Gluten can also be found in some supplements, medications and personal-care products like lip balm. Be sure to check food, drug and product labels.

Best: Opt for naturally gluten-free whole foods such as produce, fish, chicken, nuts, beans, dairy and certified gluten-free whole grains such as brown rice, buckwheat and quinoa. For more on gluten-free foods, consult the Celiac Disease Foundation,

Inflammatory bowel disease (IBD) includes Crohn’s disease, which affects the entire GI tract… and ulcerative colitis, which is limited to the colon. Symptoms can include abdominal pain, diarrhea (which may have blood in it), fatigue, low-grade fever and weight loss. If you have any of these symptoms, it’s useful to keep a detailed diet journal (record food/drinks you consume and the symptoms you experience), which will help with diagnosis and symptom relief.

The cause of IBD is not known, but there seems to be a genetic, dietary and stress component. It is diagnosed definitively by a colonoscopy, usually done by a gastroenterologist. Treatment for IBD includes various medications to reduce inflammation and suppress the immune system…stress management…avoiding certain medications, such as nonsteroidal anti-inflammatory drugs, which can irritate the bowel, and antibiotics, which can alter bacteria in the colon…and forgoing foods that you have linked to flare-ups while keeping a journal.


If unintentional weight loss is accompanied by nervousness, irritability, sleep problems, racing heart, increased perspiration and/or frequent bowel movements (but not diarrhea), hyperthyroidism (overactive thyroid) could be the cause.


Thyroid hormones regulate your metabolism—too little can result in weight gain…too much in weight loss. The more severe the hyperthyroidism, the more extreme the weight loss. A primary care physician can diagnose hyperthyroidism by checking for an enlarged thyroid gland, a rapid pulse and trembling hands. Lab tests to measure the amount of thyroid hormones in your blood will help confirm a diagnosis—a combination of high T3 and T4 thyroid hormones plus low thyroid stimulating hormone (TSH) is common in hyperthyroidism. 

An endocrinologist will map out a treatment plan, which may include medication, surgery and/or radioactive iodine to damage or destroy thyroid hormone–producing cells. In most cases, any weight that was shed will be regained once thyroid levels normalize.


Unexplained weight loss might be the first sign of cancer, particularly cancers of the pancreas, stomach, esophagus or lung. The reasons for weight loss due to cancer include changes in metabolism, depression (see below) and reduced appetite.

Treatment works best when cancer is found early, so don’t hesitate to make an appointment with your doctor to discuss concerns, especially if you’re also experiencing nausea or loss of appetite (frequent symptoms of lung, stomach or ovarian cancer)…shortness of breath or coughing up blood (lung cancer)…fatigue (leukemia)…pain (bone or testicular cancer)…or night sweats (lymphoma). Your doctor will most likely order blood tests and conduct appropriate cancer screening, then refer you to an oncologist if needed.


Nearly one in 10 Americans is battling depression at any given time. Symptoms of depression can include feeling sad, worthless or guilty…loss of interest in activities you usually enjoy…difficulty concentrating…sleep disturbances…and, yes, unexplained weight loss.


Why: The loss of energy and interest in life commonly associated with depression can severely weaken one’s appetite (however, some people overeat when depressed) and also cause someone to lose enjoyment in cooking or exercising.

A primary care physician can screen for depression and develop a treatment plan, which may include medication and/or a referral to a mental health professional for therapy. People with depression–related weight loss also can improve mood and appetite with regular exercise and better eating and sleep habits.

Other Causes

Widows and widowers sometimes find themselves suddenly responsible for meal preparation after decades of relying on their spouses. As a result, they skip meals or don’t take in enough calories. In this case, a nutritionist can help by offering advice on meal choices and preparation. Widowed individuals can also be depressed and lose weight as a result (see above).

A loss of smell (due to nasal polyps, Alzheimer’s disease, advanced age or certain medications, such as many blood pressure and thyroid drugs) can cause appetite loss and unintentional weight loss, too. An otolaryngologist can identify and treat a smell disorder by changing a drug, lowering a dosage or removing nasal polyps, for example.


Source: Robert Wergin, MD, the immediate past board chair of the American Academy of Family Physicians and a volunteer faculty member in the department of family medicine at the University of Nebraska Medical Center in Omaha. Dr. Wergin practices family medicine at the Milford Family Medical Center and is medical director of Crestview Healthcare Center, a skilled nursing community, both in Milford, Nebraska.