Can Rapid Weight Loss Cause Diabetes?

Can Rapid Weight Loss Cause Diabetes?

Can Rapid Weight Loss Cause Diabetes?

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Key Takeaways

  • Losing over five percent of your body weight without trying is considered rapid weight loss. 
  • Unintended rapid weight loss may indicate an underlying condition, like diabetes or a digestive disease, making it essential to seek medical attention. 
  • If you have diabetes and desire weight loss, it is important to avoid rapid weight loss in order to promote sustainable habits and minimize negative metabolic effects. 

You may wonder if rapid weight loss can cause diabetes. Unintentional weight loss, or losing weight without trying, does not cause diabetes, but it is a common symptom of undiagnosed diabetes. 

Rapid weight loss can lead to long-term complications like malnutrition, but it also may be a signal of an underlying medical condition. It’s important to talk to your doctor if you notice you are losing weight unintentionally. 

Continue reading to learn about rapid weight loss, its implications in diabetes, and how to lose weight safely.

Nourish offers virtual appointments with registered dietitians specializing in diabetes care. We’ll connect you with a registered dietitians who will create an individualized plan to target your concerns. Nourish accepts the most common insurance plans, making accessing the care you need easy. Start today. 

What is Considered Rapid Weight Loss?

Rapid unintentional weight loss is when a person loses at least five percent of their body weight over a period of six to twelve months without trying. For a 200-pound individual, this would mean losing a minimum of 10 lbs. 

Unintentional weight loss is defined by a decrease in body mass despite no purposeful changes in diet, lifestyle, or medication changes. Rapid weight loss is concerning because it can be a sign of an underlying medical condition and it can lead to muscle loss or malnutrition.  

Though anyone can experience unintentional weight loss, it is more common in people over 65. Regardless of age, rapid weight loss is not a symptom to be ignored. 

Can Rapid Weight Loss Cause Diabetes?

While rapid weight loss does not cause diabetes, it can be a warning sign of undiagnosed diabetes. When a person is unaware they have diabetes, blood sugar levels can become dangerously high (called hyperglycemia), which can lead to numerous symptoms, like unintended weight loss. 

Insulin is a hormone made in the pancreas responsible for delivering glucose or sugar from the foods you eat to your cells to be burned for energy. In diabetes, insulin is either not being produced (type 1 diabetes) or not being utilized properly (type 2 diabetes). This causes glucose to build up in your bloodstream, resulting in elevated blood sugar levels. 

Since the glucose remains in the bloodstream, your cells can’t use it for energy. Your body thinks it’s starving and increases appetite signals to encourage you to eat more. However, eating more won’t solve the problem because the sugar still can’t enter your cells. Many people feel confused by rapid weight loss in the context of increased hunger, and these symptoms are a sign to visit your doctor.  

The body starts to burn muscle and fat to be used for energy. Your kidneys attempt to flush out the extra sugar in your bloodstream, resulting in increased urination, which can lead to dehydration in severe cases. 

Rapid weight loss can then occur due to an energy imbalance from your body not being able to utilize glucose for energy and burning muscle and fat mass. Fluid loss from dehydration can also contribute to weight loss. 

Once diabetes treatment begins, the body can better utilize the sugar for energy, which typically stops the rapid weight loss.

Why Is Rapid Weight Loss Dangerous?

Rapid unintentional weight loss is concerning because it’s often a symptom of an underlying medical condition. If you experience a significant weight decrease without changing your diet or lifestyle and without the presence of a known medical condition, talk to your doctor. The sooner the root cause is identified, the easier it will be to treat. 

Examples of common causes of unintentional weight loss include: 

  • Diabetes.
  • Digestive issues, like chronic diarrhea.
  • Psychiatric conditions.
  • Cancer.
  • Hyperthyroidism.
  • Infections.
  • Organ failure, such as heart, lung, or kidney failure.

In diabetes specifically, rapid weight loss is a sign that blood sugar levels are too high and the body cannot utilize the energy you consume from food. This can result in loss of muscle mass since the body starts burning muscle and fat when it can’t access glucose.

One older study from 2016 found that people who experienced unintentional weight loss before being diagnosed with type 2 diabetes were at an increased risk of developing diabetic retinopathy and nephropathy (damage to the eyes and kidneys caused by chronic high blood sugar levels). This is thought to be because people who lose weight before being diagnosed often have very high blood glucose levels at that time. 

Other Signs and Symptoms of Diabetes

Not everyone experiences rapid unintentional weight loss prior to a diabetes diagnosis. However, there are other symptoms to be aware of that may indicate diabetes. If you experience any of these symptoms, talk to your doctor for a medical evaluation. 

  • Frequent urination. 
  • Increased thirst. 
  • Fatigue.
  • Increased hunger.
  • Eye changes, like blurry vision.
  • Slow wound healing.
  • Numbness or tingling of hands or feet. 

It’s estimated that one in five people with diabetes is unaware of their condition. Symptoms like unintended weight loss often come on slowly over time, making it challenging to identify a problem. Some people don’t experience any symptoms at all. 

Regular screening for diabetes is recommended, especially if you are over 45 or have risk factors like a family history of diabetes, high blood pressure, high cholesterol, elevated body weight, or prediabetes. Screening is done through a routine blood test that checks fasting blood sugar levels or hemoglobin A1c, a three-month average of blood glucose levels. 

Tips for Safe Weight Loss with Prediabetes or Diabetes

If you have prediabetes or diabetes and desire weight loss, the first step is working with your doctor to manage your blood sugar levels. This can be done through a combination of dietary and lifestyle changes and medication. Your doctor might ask you to monitor your blood glucose levels at home and will give you target ranges to aim for before and after eating. 

The diabetes plate method is a great starting point for balancing your meals. Aim to fill one-quarter of your plate with lean proteins, another quarter with high-fiber carbohydrates, and half with non-starchy vegetables. Talk to your doctor about an exercise plan that is safe for you. 

If your goal is to lose weight intentionally, it’s important to do so at a safe rate, avoiding rapid weight loss. Research shows that gradual weight loss results in greater reductions in fat mass while minimizing reductions in lean body mass and metabolic rate. On the other hand, rapid weight loss can lead to loss of muscle mass and a slower metabolism. 

The American Diabetes Association recommends a rate of weight loss of one to one and a half pounds per week for people with diabetes intentionally trying to lose weight. It’s also important to eat at regular intervals throughout the day to prevent hypoglycemia if you are on a reduced-calorie eating plan. 

For further guidance on safely losing weight, consider booking a virtual consultation with a registered dietitian through Nourish.  


Rapid unintended weight loss can be a sign of an underlying medical condition, like cancer, diabetes, or hyperthyroidism. If you experience rapid weight loss, or other common symptoms of undiagnosed diabetes, like increased urination and thirst, talk to your doctor for a medical evaluation. 

If you have diabetes or prediabetes and desire weight loss, it is important to do so gradually through balanced nutrition and sustainable exercise habits. A registered dietitian can be a helpful resource during this process. 

Managing Diabetes with an RD 

If you’ve been diagnosed with diabetes, the American Diabetes Association recommends working with a registered dietitian for guidance on blood sugar management, balanced nutrition, and weight loss if desired. 

Nourish offers virtual appointments with registered dietitians specializing in diabetes care. We’ll connect you with an online diabetes nutritionist who will create an individualized plan to target your concerns. Nourish accepts the most common insurance plans, making accessing the care you need easy. Start today.

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