If you're losing weight without trying, talk with your healthcare professional. As a rule of thumb, losing more than 5% of your weight over 6 to 12 months is a concern if the weight loss is not intentional. If you're an older adult or have ongoing medical issues, even a smaller amount of weight loss may be an important sign.

Your healthcare professional can work with you to try to figure out what's causing the weight loss. In addition to a complete exam, a health professional asks questions about:

Your healthcare professional likely also will review any recent cancer screenings. These may include a colon cancer screening test, breast exam and mammogram, or a prostate exam. This can help determine if more testing is needed.

Your healthcare professional may order blood and urine tests that can give information about your general health. Based on the results or other symptoms, you may have other tests, including imaging tests.

Sometimes, if the tests do not show a cause, watchful waiting for 1 to 6 months is a next step. Your healthcare professional may suggest you keep a food diary and track your weight.

Your health professional may suggest that you stop following a diet that limits healthy food choices and calorie intake. You may need a special diet to prevent further weight loss or to regain lost pounds. Your health professional can refer you to a dietitian, who can offer suggestions on getting enough calories.