Could Rapid Weight Loss Mean Diabetes?

An unexplained weight loss happens when you lose a significant amount of weight without a change in diet, exercise, or lifestyle. There seems no reason for it, which is why it's sometimes called unintentional weight loss.

This type of weight loss can be associated with some health conditions, such as cancer. Among them is diabetes mellitus, a group of diseases with many causes. The link between obesity and diabetes is well-known, but less so is the fact that 10% of people living with diabetes in the United States are at normal or low weights.

This article discusses why unexplained weight loss can be a red flag for diabetes. It will help you to learn more about other symptoms to watch for and how to manage weight loss with diabetes.

standing on scale

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Why Does Diabetes Cause Weight Loss?

Diabetes is a chronic disease that typically leads to other complications and systemic, or body-wide, conditions if left untreated. Among them are:

The symptoms of diabetes are often subtle and gradually become more serious. Unexplained weight loss is one such symptom. But many people don't realize they have the condition and go undiagnosed, which is the case for about 23% of people living with diabetes in the United States.

Other symptoms most often associated with diabetes include:

  • Feeling more hungry and/or thirsty than usual
  • Frequent urination
  • Blurry vision

Insulin, Glucose and Weight

Glucose is a sugar released into the bloodstream when you eat and drink. The pancreas makes insulin in response to the higher sugar levels in your blood. The body needs this hormone to release glucose to all its cells. With diabetes, the glucose builds up in your bloodstream. You may lose weight because the body needs an energy source and burns fat and muscle instead.

Types of Diabetes

There are three main types of diabetes, all of which are treated differently. There are also other health conditions that can raise the risk of diabetes, such as while people are taking steroid drugs or when they are living with cystic fibrosis, a genetic disease with body-wide impacts.

Type 1 Diabetes

Type 1 diabetes is an autoimmune disease. This means the body's immune system mistakenly attacks healthy tissues and destroys the insulin-producing cells of the pancreas. The damage from these attacks causes the pancreas to stop making insulin. Type 1 diabetes can appear at any age but usually develops in children or teens.

Type 2 Diabetes

Type 2 diabetes happens when the pancreas doesn't make enough insulin or the body doesn't use it properly. People usually acquire type 2 diabetes later in life, although rising childhood obesity rates mean more children are developing type 2 diabetes. Being overweight is a primary risk factor for type 2 diabetes. It's the most common form.

Gestational Diabetes

Gestational diabetes is a temporary condition that happens when a person is pregnant. It usually resolves after the baby is born. It's not weight loss, but rather weight gain, that is a concern in these cases. It's also more common in people who are already overweight or obese.

How Much Weight Loss Is a Concern?

Unexplained weight loss happens when you lose significant weight without a change in diet or exercise, or without making other lifestyle changes.

Healthcare providers become concerned when there is a loss of 10 pounds or more, or 5% of body weight, during a period of six to 12 months. When they look to find a reason for the weight loss, especially in people age 65 and older, they find an underlying medical condition is at work in 72% of cases.

Weight Loss in Children

Unexplained weight loss can occur in people who have type 2 diabetes, but it’s more common in people with type 1. Type 1 diabetes usually affects children and adolescents. Parents are often the first to notice an unusual weight loss in a child with type 1 diabetes.

Weight loss in kids with diabetes can occur even in those who have a normal or increased appetite for the same reasons it happens in adults with diabetes. Once kids are diagnosed and treated for diabetes, weight loss ceases and typically returns to normal.

Other Symptoms

Symptoms of diabetes are often too subtle and gradual for people to recognize. Weight loss is just one possible indicator.

Excessive thirst, hunger, and urination are classic signs of diabetes, but they also can lead to the body's dehydration, or lack of water. Prolonged dehydration can cause:

  • Fatigue
  • Nausea
  • Headaches
  • Dizziness
  • Rapid breathing
  • Fainting

Dehydration also may cause you to urinate less often, which allows blood sugar to build up in the bloodstream. When this happens, blood sugar levels rise too fast.

Be sure to watch for these other signs of diabetes, too:

  • Itchy skin: Diabetes caused by high blood sugar can make someone prone to dry skin. Skin infections or poor circulation can also contribute to dry, itchy skin.
  • Dark skin around the neck and armpits: Dark skin in the neck folds and over the knuckles sometimes appears before a diabetes diagnosis. Insulin resistance can cause this condition, known as acanthosis nigricans.
  • Cuts and bruises that don't heal: Having high or poorly controlled blood sugar for a long time can lead to poor circulation and nerve damage, which can make it difficult for the body to heal wounds. The feet are most susceptible. These open wounds are called diabetic skin ulcers.
  • Yeast infections: When blood sugar is high and the kidneys can’t filter it well enough, sugar is released through the urine. More sugar in a warm, moist environment can cause urinary tract and yeast infections, especially in women.
  • Unusual fatigue: Several underlying causes of fatigue may relate to high sugar levels, including dehydration and kidney damage.
  • Mood changes: This can include irritability.
  • Vision changes: Early on, people with diabetes may have trouble reading or seeing far away objects. In later stages of diabetes, they may see dark, floating spots or streaks that resemble cobwebs. 

In Children

Increased urination and thirst are early signs of diabetes in children, just as they are in adults. These symptoms lead to dehydration, which can quickly become more serious in young children than it is in adults.

A child who is constantly thirsty, drinks more fluids, and needs more bathroom breaks throughout the day may be doing so because of high blood sugar levels. In babies, keep an eye out for sunken eyes or cheeks, no tears when crying, and not enough wet diapers.

Diabetes can be life-threatening if left untreated. If your child is showing signs of diabetes, it’s important for you to schedule a healthcare provider’s appointment as soon as possible.

Other symptoms that affect kids with diabetes may include:

  • Fatigue: If a child is often tired, it may be a clue that their body is having trouble converting sugar in the bloodstream into energy.
  • Vision changes: High blood sugar levels can cause blurred vision and other eyesight problems.
  • Fruity smelling breath: This sign could be indicative of too much sugar in the blood.
  • Extreme hunger: When a child's muscles and organs aren’t receiving enough energy, it can cause extreme hunger.
  • Unusual behavior: If a child seems moodier or more restless than normal—and it’s in conjunction with other symptoms that could indicate diabetes—it could be cause for concern.
  • Nausea and vomiting
  • Heavy breathing

Managing Weight Loss With Diabetes

To manage weight loss with diabetes, you'll first need to get your blood sugar under control. You'll need to work together with your healthcare provider on a treatment plan toward this goal, which may involve different strategies depending on your disease.

Diet, exercise, and other lifestyle changes work for some people with diabetes who aren't taking medication. Many people with type 1 diabetes—and some with type 2—will need to take insulin or other drugs to ensure their blood sugar levels stay well-controlled.

Typically, once someone is treated for diabetes and their blood sugar normalizes, their weight loss will stabilize. It is critical to continue to monitor diabetes under a healthcare provider's care at home because it is a lifelong condition.


It's true that being overweight can place you at higher risk for diabetes, but it's the loss of weight that may be a sign that you have developed the disease. This unexplained weight loss is one of many possible symptoms, including the need to eat and drink more.

This may happen because your body's cells aren't getting the glucose energy they need, which normally comes from your meals. They start to burn fat and muscle instead.

To manage your unexplained weight loss, you'll need to know what's causing it. Diabetes may be the reason, especially when other symptoms are present. Once you have your blood sugar under control, your weight concerns may resolve.

Frequently Asked Questions

  • Can Meal Planning Help With Diabetes and Weight Conrol?

    Yes. People living with diabetes have to watch what and how they eat to manage their lifelong condition. Good diet plans, along with exercise and healthy lifestyle choices, will help you to manage your weight as well as your blood sugar levels. Talk with your healthcare provider or dietitian to ensure you're getting the nutrients you need from foods you'll enjoy.

  • What Is a Certified Diabetes Care and Education Specialist (CDCES)?

    The CDCES is a health professional who can help you to achieve your weight goals while maintaining a balanced diet. They look at your diet within the context of your whole life and your medical history and work to support your success in managing your diabetes. You can learn more about them from the Association of Diabetes Care & Education Specialists.

13 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Cherie Berkley, MS
Cherie Berkley is an award-winning journalist and multimedia storyteller covering health features for Verywell.