Unexplained Weight Loss: What Could It Mean?

Unexplained weight loss could be due to dangerous underlying causes, from infections, to disorders, to conditions as serious as congestive heart failure and cancer. 

Under normal circumstances, people have to work hard to control their weight, whether they’re trying to slim down or bulk up. Sudden, noticeable, weight loss is often a symptom of an underlying health concern, and unexplained weight loss is even more worrying, as it could be an indication that something is wrong with your body, but is currently undiagnosed. This article will detail some of the usual suspects behind unintentional weight loss, so you can better understand how important it is to identify the underlying cause.

How Much Weight Loss Is Concerning?

It’s common to fluctuate between 1-3 pounds per day according to your scale; those are just the vagaries of water weight. However, a loss of 10 pounds or more (or 5% of your body weight) over a 6-12 month period with no known reason warrants concern. If you’ve changed your habits, changed your diet, or undergone a change in life that could explain the reduction in weight, then it may not be that unusual, but you may benefit from asking yourself some questions.

  • Did you start a new job?
  • Did you move to a new area?
  • Are you under some known form of stress (whether happy or unfortunate—i.e. planning a wedding or caring for a sick loved one).
  • Has there been a change in your relationship status?

It’s important to know, because while this sort of steady weight loss would be welcome if you’d changed your diet with the intention to lose weight (by transitioning from processed to whole foods for example), if no alterations to your diet or lifestyle have been made and your weight has still gone down this dramatically, there may be some serious underlying reasons.

Losing Weight Without Trying: Am I Sick?

Unexplained weight loss could be the first sign of sickness, yes. You should contact a doctor or health care professional right away to seek evaluation, as the causes for unexplained weight loss can be quite serious, from infections, to thyroid issues, to the terrifying prospect of cancer (but please don’t go to the extreme scenario…just go to a doctor!).

The good news is that doctors quickly find the cause of abnormal weight loss in over 75% of cases. In fact, even if you think you know the cause, something like general stress and anxiety could be masking a physical health problem, and you should make an appointment to be sure this weight loss isn’t caused by a combination of issues or that it isn’t taxing your health in other ways.

If the first examination isn’t thorough enough, seek a second opinion to rule out other causes. Blood tests, a urinalysis, a thyroid panel, liver and kidney function tests, a blood sugar test, or imaging studies may need to be done to make sure there are no red flags in your health profile.

Your doctor may ask:

  • Have you made any changes in your exercise or diet recently?
  • Has this sort of weight loss ever happened to you before?
  • Do you have any dental problems or mouth sores that could impede your ability to eat normally?
  • Is there a history of any particular illness that runs in your family?
  • Do you have any other concerning symptoms (palpitations, excessive thirst, sensitivity to heat or cold, a persistent cough, shortness of breath)?

Consider your overall health as you prepare for your appointment, so you can make sure your doctor is informed of any symptom that might be relevant to your condition.

Why Diagnosis Is Important

There are many medical conditions that might lead to unintentional weight loss. The American Cancer Society points out that 50% of all cancer patients have a form of cancer cachexia, a wasting syndrome that involves unintentional weight loss and brings on the death of about 20% of cancer patients.

It is the same with cardiac events. One study explicitly states, “Unintentional weight loss was an independent predictor of poor outcomes.” Unintentional weight loss brings about higher morbidity, mortality, and bodes ill for anyone already battling a disease. That is why identifying and treating unexplained weight loss is so important, especially in older adults (above age 65), who are all the more at risk of serious consequences from any sudden change in health.

Possible Causes of Unexplained Weight Loss

We’ll now run down some of the common causes of unintentional or abnormal weight loss.

Unexplained weight loss: possible underlying causes.

Endocrine Conditions

Endocrine conditions include hyperthyroidism (an overactive thyroid), hypothyroidism (an underactive thyroid), diabetes, and Addison’s disease (wherein the adrenal glands don’t produce enough hormones). The thyroid gland is located in your neck, is somewhat butterfly-shaped, and controls your metabolism. An issue with the thyroid gland could be accompanied by heart palpitations, and if type 2 diabetes is at play, you’re likely to experience increased thirst and excessive urination as your body tries to expel all the glucose it can’t absorb.

Infections

Infections include anything from parasites, bacterial infections, and viruses (which HIV/AIDS patients are more susceptible to), along with conditions like endocarditis (an infection of the heart valves), or tuberculosis (an infection of the lungs). In these instances, your body is losing weight because it is using all of its resources to fight off an invasion.

Cancer

Weight loss can sometimes be one of the earliest symptoms of cancer, such as from lung cancer, ovarian cancer, colon cancer, pancreatic cancer, or blood-related cancers like lymphomas and leukemias. About 40% of cancer patients report having experienced weight loss around the time of their diagnosis, and studies have shown that unintentional weight loss is the second highest predictor for certain cancers. Weight loss often occurs as a result of cancer due to the body’s nourishing efforts being hijacked to support an abnormal tumor growth. Doctors will often check first for tumors in the bowels, colon, and esophagus, which can impede swallowing and quickly contribute to unintentional weight loss.

Intestinal Conditions

Conditions like celiac disease, peptic ulcer disease, Crohn’s disease, ulcerative colitis, and pancreatitis can lead to unexplained weight loss in those who have yet to be diagnosed.

Celiac disease is an autoimmune disorder wherein the small intestine is damaged by gluten intake, leading to GI symptoms like diarrhea and bloating. According to the Mayo Clinic, when the immune system sees gluten as a threat, it reacts, and that reaction means your body doesn’t have a chance to absorb its nutrients properly. Likewise, in an inflammatory bowel disease like Crohn’s, the body’s reaction leads to malabsorption and unexplained loss of weight.

Those with chronic pancreatitis lose weight due to the fact that their body cannot produce enough digestive enzymes to properly break down food (and this may come with nausea, particularly from eating fatty foods).

Heart Failure

Congestive heart failure may cause weight loss due to a lack of sufficient blood flow to the GI tract. In a 2014 study researchers observed that those who had the most dramatic unintentional weight loss were indeed those who had the lowest blood flow to their intestines. Inadequate blood flow makes it harder to absorb nutrients, and the nausea and fatigue associated with congestive heart failure could lead to a loss of appetite.

Eating Disorders

Eating disorders like bulimia and anorexia nervosa can cause dangerous weight loss, and while it might not be a completely unknown cause to the person suffering from the condition, it can be an indicator to a loved one or parent that something is wrong. Moreover, because of the nature of body dysmorphia, those coping with these eating disorders may not fully realize just how significant their weight loss is until it starts causing other health symptoms due to malnutrition.

Psychological Conditions

Depression and anxiety disorders often come with loss of appetite as a side effect, and can be an underlying cause of unexplained weight loss. It often goes unnoticed until the weight loss is significant enough, and will involve a different sort of diagnosis, as these are not conditions that can be found via imaging scan or blood test.

Drug Abuse

Be they extralegally obtained drugs or prescription medications, drug dependence can alter your body’s metabolic and digestive processes, and change your eating habits. Side effects from medications could lead to nausea, loss of appetite, or laxative effects that can contribute to unintentional weight loss as well.

Neurological Conditions

Unintentional weight loss is frequently seen in those with Parkinson’s disease and Alzheimer’s. This is possibly due to the increased energy expense of rigidity, tremors, or dyskinesia (involuntary movements) associated with Parkinson’s, or the reduced energy intake due to poor health, stress, or the side effects of medication.

Rheumatoid Arthritis

When the immune system causes inflammatory reactions in healthy tissues, as in those with rheumatoid arthritis, it can also lead to a loss of appetite or an inflammation of the gut that interrupts nutrient absorption.

Reproductive Issues

Unexplained weight loss during menopause is unnatural, as it’s more common that menopause cause weight gain in women experiencing the change. Unintentional weight loss surrounding menopause could indicate that the changes in hormones has caused or made you susceptible to some other condition (stress, diabetes).

Likewise, unexplained weight loss during pregnancy is the opposite of the normal course of order. In the first few months, a loss of appetite due to morning sickness could be the culprit behind unintentional weight loss, but excessive weight loss could be a sign of a thyroid dysfunction or hyperemesis, a pregnancy complication that entails vomiting, severe nausea, dehydration, and weight loss. Your obstetrician should be made aware of any such symptoms.

An Explanation Is Necessary

Unknown causes of weight loss include a lot of scary and potentially life-threatening concerns. It’s normal for your weight to fluctuate by a few pounds here or there throughout the course of the year, but if you cannot determine a cause for sudden, steady weight loss, it’s important to consult with a medical professional and investigate: in fact, it could save your life.