Unintended weight loss may have medical and nonmedical causes. Often, a combination of things results in changes in your health and related weight loss. Sometimes, a specific cause of weight loss isn't found.

Most often, medical or mental health conditions that cause weight loss have other symptoms.

Potential causes of unintended weight loss include the following.

Cancer

1. Cancer particularly in the digestive tract.
2. Kidney cancer
3. Liver cancer
4. Lymphoma
5. Pancreatic cancer

Hormone-related conditions

1. Adrenal cancer and other conditions of the adrenal gland.
2. Diabetes
3. Hyperthyroidism (overactive thyroid)

Economic, social and physical factors

1. Dental pain, gum disease or poorly fitting dentures that make it hard to eat.
2. Limited ability to shop for food or prepare meals.
3. Limited income or limited access to healthy food.
4. Physical disabilities that make it hard to use cooking or eating utensils.

Mental health and substance use

1. Alcohol use disorder
2. Depression (major depressive disorder)
3. Mood disorders
4. Drug addiction (substance use disorder)
5. Eating disorders
6. Prescription drug abuse
7. Side effect of medicines, supplements or herbal products.

Digestive system conditions

1. Celiac disease
2. Inflammatory bowel disease (IBD)
3. Peptic ulcer

Nervous systems conditions

1. Dementia
2. Parkinson's disease

Long-term conditions, particularly in later stages of disease

1. Cirrhosis
2. COPD
3. End-stage renal disease
4. Heart failure
5. HIV/AIDS
6. Tuberculosis