Benefits of a Low-Carb Diet for Prediabetes and Diabetes

Dr. Tashko explains the physiology and importance of a low-carb diet for prediabetes and diabetes. It improves insulin resistance, glucose control, weight loss, and overall metabolic health among other benefits.

Introduction – Prediabetes & Diabetes Care in Montgomery County, Maryland

As a board-certified diabetologist, I am dedicated to providing the highest quality care in preventing and treating prediabetes and diabetes in my community. I specialize in offering personalized treatment plans for patients with insulin resistance, type 2 diabetes, and other metabolic disorders, utilizing a comprehensive, evidence-based approach.

Conveniently located in Rockville, my practice offers virtual and in-person services, extending support to nearby areas such as Chevy Chase, Bethesda, North Bethesda, Potomac, North Potomac, Gaithersburg, Germantown, Frederick, Silver Spring, Northern Virginia, Howard County, Anne Arundel, and the Eastern Shore of Maryland, ensuring comprehensive care. 

Now, let us delve into the significance and benefits of a low-carb diet in preventing and managing prediabetes and diabetes.


Diabetes affects millions worldwide. Prediabetes, a precursor to diabetes, indicates elevated blood sugar levels that are not high enough to be classified as diabetes. Managing both conditions is key to preventing complications like heart disease, nerve damage, and vision problems. One effective way to manage blood sugar levels is through dietary changes, particularly a low-carb diet.

Understanding Prediabetes & Diabetes

Prediabetes occurs when blood glucose concentration is higher than normal but not sufficiently high for a diabetes diagnosis. If untreated, prediabetes can progress to type 2 diabetes. Both conditions involve insulin resistance or insufficient insulin production, leading to elevated blood glucose levels.

Physiological Perspective

1. The Role of Carbohydrates

Carbohydrates are the body’s primary energy source. They eventually break down into glucose, which enters the bloodstream. This process triggers insulin release from the pancreas, allowing cells to use glucose for energy. However, in prediabetes and diabetes, this system doesn’t work correctly. Limiting carbohydrate intake can help manage blood sugar readings more effectively.

2. The ‘’Stored Glucose” by the Liver

The liver stores glucose as glycogen in response to excessive carbohydrate intake. During periods of prolonged fasting, the liver releases glycogen as glucose into the bloodstream to maintain normal blood glucose levels. When a person consumes fewer carbs, the liver breaks down more glycogen stores to provide glucose. As this process continues, the glycogen supply eventually depletes, leading to lower serum glucose levels. This reduction in glucose helps improve blood sugar control in individuals with prediabetes and diabetes.

3. Switching to Fat for Energy

As glycogen supplies deplete, the body shifts to using fat for energy. This process, known as ketosis, involves the liver producing ketone bodies from fats. Ketone bodies serve as an alternative energy source, particularly for the brain, which can efficiently use ketones for fuel. This switch to fat metabolism can aid weight loss, a key factor in managing prediabetes and diabetes.

Benefits of the Low-Carb Diet

1. Blood Sugar Control

A low-carb diet helps stabilize blood sugar concentration, reducing the spikes and crashes associated with high-carb meals. By keeping blood glucose readings consistent, individuals with prediabetes and diabetes can manage their condition better and lower the risk of complications.

2. No Hypoglycemia

One theoretical concern with low-carb diets is the risk of hypoglycemia, or low blood sugar. However, the body has adaptive mechanisms to prevent this. When glycogen stores are emptied, the liver activates gluconeogenesis, a process that produces glucose from fats and amino acids. This ensures a steady supply of blood glucose even with low carbohydrate intake.

3. Weight Loss & Insulin Sensitivity

A low-carb diet, combined with reduced daily caloric intake, significantly aids in weight loss. Excess weight is a major risk factor for insulin resistance, a key feature of prediabetes and type 2 diabetes. By losing weight, individuals can improve their insulin sensitivity, making it easier for their bodies to use insulin effectively and manage blood sugar levels.

4. Fewer Diabetes Medications

As mentioned above, a low-carb diet lowers blood glucose concentration, improves insulin performance, and promotes weight loss. This can reduce reliance on medications like insulin, sulfonylureas, metformin, GLP-1 agonists, or SGLT-2 inhibitors. Patients may need lower doses or might stop these medications altogether.

5. Improved Energy & Mental Clarity

Many people on low-carb diets report improved energy levels and mental clarity. This is partly due to the stable blood glucose concentration and the brain’s efficient use of ketones for energy. Better energy levels and mental function can enhance overall quality of life and make it easier to maintain healthy habits.

Practical Tips for a Low-Carb Diet

  • Choose Non-Starchy Vegetables: Fill your plate with vegetables like leafy greens, broccoli, and bell peppers. These are low in carbs but high in nutrients.
  • Opt for Healthy Fats: Include sources of healthy fats like omega-3s, avocados, nuts, seeds, and olive oil. These fats can help you feel full and satisfied.
  • Select High-Quality Proteins: Focus on lean proteins such as fish, poultry, and tofu. Protein helps maintain muscle mass and keeps you full.
  • Limit Sugary Foods and Drinks: Avoid sugary snacks, desserts, and beverages. These can cause blood sugar spikes and contribute to weight gain.
  • Stay Hydrated: Drink plenty of water to stay hydrated and support your body’s metabolic processes.
  • Monitor Your Blood Sugar: Regularly check your serum glucose readings to see how your diet affects them. This can help you make necessary adjustments.

Success Stories & Evidence

Clinical experience, studies, and personal success stories highlight the benefits of a low-carb diet for diabetes management. Research shows that low-carb diets can lead to significant improvements in blood sugar control, weight loss, and a reduction in diabetes medications.

For instance, a 2018 study in Diabetes Therapy found that a low-carb diet helped people with Type 2 diabetes. After six months, participants saw significant reductions in hemoglobin A1C levels, a marker of long-term blood sugar control. A 2022 study in The JAMA Network reported similar findings. Participants showed improved insulin sensitivity and hemoglobin A1C


A low-carb diet can be a powerful tool for managing prediabetes and diabetes. By reducing carbohydrate intake, you can lower blood glucose levels, promote weight loss, and improve insulin sensitivity. Additionally, the body’s ability to switch to fat metabolism and produce glucose through gluconeogenesis ensures stable energy levels without the risk of hypoglycemia. With careful planning and monitoring, a low-carb diet can significantly enhance your health and quality of life. 

Dr. Tashko