Unexplained Weight Loss: When to see a healthcare provider

Losing weight when you’re not trying can feel like good news, but it’s worth paying attention to. Doctors generally look into losing more than 5% of your body weight over 6 to 12 months without explanation.

Imagine your clothes getting loose, and friends complimenting your weight loss, but you haven’t changed anything. You’re also thirsty all the time and up at night to pee. A blood test shows diabetes. Treatment brings your weight and energy back into balance.

Common causes

• Stress, anxiety and depression, which affect appetite
• Overactive thyroid, often with a fast heartbeat, sweating and shakiness
• Diabetes, with thirst and frequent urination
• Gut conditions such as coeliac disease, Crohn’s disease or ulcerative colitis
• Infections such as tuberculosis or HIV
• Dental problems or difficulty swallowing
• Medicines and substance use
• Cancer, sometimes as an early sign

In older adults, weight loss can also follow loneliness, difficulty shopping or cooking, dementia or reduced sense of taste.

But when should I see a healthcare provider?

See a healthcare provider if you’ve lost a noticeable amount of weight without trying, especially with any of these: tiredness, fever or night sweats, a change in bowel habit, blood in stool or urine, a persistent cough, difficulty swallowing, ongoing tummy pain, or a new lump. Tests often start with blood tests and a check-up, then further investigation if needed.

If someone close is losing weight and seems to be restricting food deliberately, gently encourage them to get support for a possible eating disorder.

Sources: NHS (Unintentional weight loss), Mayo Clinic, Cancer Research UK, American Academy of Family Physicians.