Losing weight suddenly? 10 causes of unexplained weight loss you shouldn’t ignore

Are you losing weight unintentionally? Check out the potential reasons for unexplained weight loss and what you can do.
weight loss
Here's what causes sudden weight loss. Image courtesy: Adobe stock
Shruti Bhattacharya Published: 25 Mar 2024, 08:59 am IST
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I was shredding a lot of pounds daily but was neither following any diet nor doing any workout. Initially, it made me happy but the sudden weight loss made me worry a little. While keeping your weight in check is a good thing, losing too much of it unintentionally could be a cause of concern. You must investigate the cause because it could suggest a condition that is destroying both your physical and mental health. Unexplained or unintentional weight loss may appear to be a good thing but investigating the possible causes is critical.

According to a study cited by PubMed Journal, at least 72 percent of patients who experience unexplained weight loss suffer from an underlying illness. That’s why you should always consult your healthcare provider if you have been losing weight unintentionally. Let’s find out the root cause of unexplained weight loss and how to prevent and treat it.

What is unexplained weight loss?

A noticeable decrease in body weight that happens even when a person is not attempting to lose weight is known as unexplained weight loss. Sudden weight loss does not come about because of diet, exercise, or lifestyle changes. A medical evaluation is necessary if you lose more than 5 percent of your weight in 6 to 12 months, without making an effort to lose weight. For example, a 5 percent weight loss in someone who is 72 kilograms is 3.6 kilograms, explains Internal Medicine, Dr Tushar Tayal.

According to a study published in the Canadian Medical Association Journal, weight loss can result from a range of medical, psychological, and social factors as well as age-related changes.

A woman on a weighing scale
Several diseases can cause unexplained weight loss. Image courtesy: Pexels

What are the causes of unexplained weight loss?

Here are some of the major reasons for unexplained weight loss, as explained by the expert.

1. Hyperthyroidism or overactive thyroid gland

The thyroid gland produces thyroxine hormone which controls metabolism. Sometimes autoimmune disorders or viral infections of the thyroid can cause it to become overactive, leading to excessive thyroxine hormone production called hyperthyroidism, which can cause significant weight loss.

2. Diabetes

There are two main types of diabetes: Type 1, an autoimmune condition, and Type 2, which typically appears later in life as a result of improper insulin synthesis or processing. Gestational diabetes is the third kind of diabetes that manifests itself during pregnancy and is transient. Both kinds of diabetes can cause unexplained weight loss, but Type 1 diabetes is more likely to cause it.

3. Mood disorder

For people with mood disorders such as anxiety and depression, there may be appetite loss leading to decreased food intake and weight loss. Plus, changes in eating patterns brought on by depression may result in weight reduction. Many people from all walks of life are impacted by depression, and one in six people may deal with depression at some point in their lives, according to the data by Centers for Disease Control and Prevention.

4. Cancer

As per a study published in the British Journal weight loss may be the first symptom of blood cancers such as leukaemia and lymphoma, or solid tumours like lung cancer (particularly adenocarcinoma of the lung), colon cancer, ovarian cancer, and pancreatic cancer. Recurrence of an early-stage tumour (like breast cancer) can also result in sudden weight loss.

5. Addison disease

Addison’s disease is an endocrine condition characterised by difficulties with the adrenal glands located on top of each kidney. These glands create essential hormones, or chemical messengers, such as cortisol. The absence of these hormones in Addison’s disease could lead to weight loss, exhaustion, and other symptoms, as per a study published in the National Institute of Diabetes and Digestive and Kidney Disease Journal.

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6. Stress

Stressful life events such as divorce, the death of a family member, or financial issues can lead you to lose appetite, miss meals, or eat less than normal. This can cause unexplained weight loss.

7. Lupus

Lupus is an autoimmune disease that leads your immune system to wrongly target healthy cells. It can impair your body’s capacity to absorb nutrients and create issues with your digestive system. Lupus often causes loss of appetite. Inadvertent weight loss occurs in 15-17 percent of patients with this illness. The weight loss will usually be apparent before the diagnosis, according to research published in the Arthritis and Care Research Journal.

8. Neurological disorder

A prevalent sign of neurological diseases like Parkinson’s, Alzheimer’s, and Huntington’s is early weight loss. According to a study published in the American Academy of Journal, alterations in the brain’s metabolism of proteins that increase the need for energy may be linked to weight loss in certain conditions.

9. Kidney failure

Loss of appetite and nausea can lead to weight loss, but so can a shift in fluid retention in an individual with kidney disease.

Potter Syndrome
In some cases, kidney disease can lead to sudden weight loss. Image courtesy: Adobe Stock

10. Alcohol and drug abuse

Reduction in appetite, nausea, vomiting, mental health issues, and lifestyle changes can all contribute to weight loss in individuals with alcohol use disorders. Malnutrition can occur as a result of severe liver disease in people with long-term alcohol use disorders, which can lead to weight loss.

How to prevent unexplained weight loss?

If you’ve been losing weight without doing anything, don’t take it lightly! It could be a sign of a serious disease that should be addressed immediately. You must consult a physician and get investigated for the same. Plus, it is not always possible to avoid unexplained weight loss. It is crucial to inform your healthcare practitioner if you observe any changes in your appetite or weight. This is the best way to keep an eye on your weight and an underlying health problem.

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About the Author

Shruti Bhattacharya is a content writer and editor for over 2 years. She specialises in writing on a variety of topics such as wellness, lifestyle, beauty, technology and fashion. Her current focus is on creating factually correct and informative stories for readers. ...Read More

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