Unintentional Weight Loss in Adults

Welcome to our Decision Guide on Unintentional Weight Loss.

This guide is designed to provide insight as to why you are losing weight without purposefully trying to diet. The guide should be used as a complement to the care you receive from a health professional. It is not intended to replace direct interaction with your doctor.

Doctors become most concerned about unintentional weight loss if it reaches more than five percent of the usual body weight (about ten pounds), especially if your weight has not stabilized and continues to go down.

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It is quite common for weight to fluctuate a few pounds in either direction. People who tend to retain fluid and get swollen legs can quickly lose several pounds of water over one to two days. This is especially true if a person takes water pills (diuretics).

Weight loss related to water only is not the subject of this guide. Weight loss in this guide refers to a decrease in "dry" weight.

Most people who lose weight and are concerned about it often have a diminished appetite.

Has your appetite decreased?

Yes, my appetite has decreased.

No, my appetite is still good.

Sometimes people remain hungry and look forward to eating while still losing weight. Maintaining a good appetite while unintentionally losing weight suggests a different set of possibilities.

A person who has become physically much more active can burn more calories than they take in. This is usually pretty obvious and it takes a lot of exercise to get there. Other causes of losing weight while maintaining a good appetite include an overactive thyroid, diabetes and eating disorders such as bulimia.

With an overactive thyroid, your metabolism increases and you burn more calories.

Do you have some of the following symptoms:

  • hand tremor

  • feeling hot and sweaty

  • a swelling in the front of your neck

  • feeling jittery and anxious

  • palpitations?

Yes, I have one or more of these symptoms.

No, I do not have any of these symptoms.

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