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Unplanned Weight Loss

Condition Basics

What is unplanned weight loss?

Unplanned weight loss means losing weight without trying to. It may be caused by a medical problem, so be sure to see your doctor if you are losing weight without trying. If you are losing weight because you're exercising more or eating less, that's normal weight loss.

What causes it?

Lots of medical problems can cause you to lose weight without trying. These problems include:

  • An overactive thyroid gland.
  • Long-term infections.
  • Mouth or throat problems that make it hard to eat.
  • Digestive problems.
  • Depression.
  • Diabetes.
  • COPD (chronic obstructive pulmonary disease).
  • Cancer.

Other causes of unplanned weight loss include taking certain prescription and over-the-counter medicines.

In older adults, memory problems such as dementia can lead to weight loss.

How is unplanned weight loss treated?

If your weight loss is caused by a medical problem, such as an overactive thyroid gland, digestive problems, or depression, your doctor will treat that problem. Your doctor may also suggest a change in what you eat. In some cases, the doctor may prescribe medicines that help you gain weight.

What can you do to gain weight?

There are several things you can do to help gain back any weight you lost.

  • Talk to your doctor about what you can do to gain weight.

    Don't use expensive supplements for quick weight gain. Your doctor may suggest that you see a dietitian, who can help you make a meal plan that fits your lifestyle.

  • If your doctor says it's okay, find ways to eat more high-calorie, nutritious foods.

    These foods include:

    Put cheese on crackers or sandwiches, or add it to soups and salads. Eat string cheese as a snack.
    Dried fruits or nuts.
    Put dried fruit on cereal or in salads or yogurt. Put nuts on mashed potatoes or ice cream or in a gravy.
    Granola bars.
    Carry them with you as a snack.
    Peanut butter.
    Use it in a sandwich, or spread it on bread, bagels, bananas, or celery.

When should you call the doctor?

Call your doctor if:

  • You are following your meal plan but are not gaining weight.
  • You are following your doctor's treatment plan but are not getting better as expected.
  • You start to have other symptoms, such as belly pain, vomiting, or changes in how often you have a bowel movement, the color or size of your stools, or how solid they are.


Current as of: October 2, 2023

Author: Healthwise Staff
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.