Unexplained sudden weight loss, constant hunger, and fatigue

Sudden unexplained weight loss is a classic symptom of type 1 diabetes, resulting from insulin deficiency, with a loss of the hormonal action of insulin in inhibiting the breakdown of protein in the body. In type 1 diabetes, weight loss may take the form of muscle wasting and a loss of muscular strength, especially as it occurs in young men. Weight loss in type 1 diabetes may also be accompanied by extreme, constant hunger (polyphagia), as well as fatigue, as the body lacks the ability to use glucose. Additionally, fatigue or lethargy may also be a sign of diabetic ketoacidosis.1

Diabetic ketoacidosis is a dangerous short-term complication of diabetes. It results when chemicals called ketones accumulate in the blood. Because a person with diabetes is unable to use glucose for energy, if they are not being treated properly, their body may burn fat instead to get energy. Burning fat causes the production of ketones, which can be toxic if they build up in the blood. In addition to fatigue or lethargy, weight loss, extreme thirst, frequent urination, stomach ache and nausea, and difficulty thinking clear are signs and symptoms of ketoacidosis. In extreme cases, ketoacidosis can cause a person to go into a coma. So, this complication should be treated as a medical emergency. If you experience any of the symptoms ketoacidosis, you should consult your healthcare provider.2,3

Learn more about diabetic ketoacidosis

Sudden weight loss is also less frequently a sign of type 2 diabetes. However, its mechanism is entirely different compared with weight loss associated with type 1 diabetes. In type 2 diabetes, weight loss may result from dietary restriction on the part of an individual who senses a health problem and deliberately attempts to change eating habits. More typically, type 2 diabetes is associated with weight gain, instead of weight loss.1,4

Fatigue resulting from a failure of glucose transport to muscle, as well as excessive hunger in response to a failure of glucose metabolism may also a sign or symptom of type 2 diabetes.1,4

What should I do if I experience these symptoms?

If you experience some or all of these symptoms and you have not been diagnosed with diabetes, you should see your doctor and discuss your symptoms. Your doctor will evaluate you and identify the cause of the symptoms. As part of this evaluation, your doctor will measure your blood glucose to determine if it is high and whether you may have diabetes. If you have already been diagnosed with diabetes, these symptoms are signs that your blood glucose is out of control. Your doctor will work with you to help you control your blood glucose, using lifestyle modifications, including a healthy, calorie-appropriate eating plan, regular physical activity, and weight loss, and, if these modifications are not enough, medication.

Learn more about lifestyle modifications that I can use to help control my blood glucose.

Learn more about medications that I can use to help control my blood glucose.

Written by: Jonathan Simmons | Last reviewed: May 2014.
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