Do People With Diabetes Have to Follow a Low-Carb Diet?

How a low-carb diet may affect your blood sugars

Complex carbohydrates are okay for a person with diabetes.
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If you're living with type 2 diabetes, you may be wondering if you should follow a low-carb diet. In fact, some recent studies suggest that a very low-carbohydrate diet may be able to reverse type 2 diabetes. Learn about the role of carbohydrates in a healthy diet for people with diabetes and what some of the current research says about the impact of low-carb or very low-carb diets on blood sugar.

The Role of Carbohydrates in Our Diet

Carbohydrates include sugars and starches and together they make up one group of macronutrients; the other two are protein and fat. When you consume carbohydrates, your digestive system breaks them down into individual sugar units that are absorbed into your blood. This triggers the release of insulin, a protein that helps move glucose out of your blood and into your body's cells so it can be used for energy. Sugars that aren't immediately used for energy are either stored or converted to fat (when you eat more food than your body needs).

You need to consume carbohydrates every day because they are your body's primary energy source. The Academy of Nutrition and Dietetics and the U.S. Department of Agriculture's 2020–2025 Dietary Guidelines for Americans recommend that you get about half of your daily calories (45–65% of calories) from nutrient-dense carbohydrate sources, which is between 900 to 1,300 calories in a 2,000 calorie diet.

According to the USDA, that's an average intake of about 130 grams of carbohydrates per day for most people. But this number can vary depending on an individual's age, sex, weight, height, and level of physical activity.

History of Carbohydrates in a Diabetic Diet

For people with diabetes, the recommended daily intake of carbohydrates has a roller-coaster history and remains somewhat an area of controversy. Before insulin or diabetes medications were available, eating a low-carb diet was the only treatment available. That changed with both the discovery of insulin and medications, as well as with the knowledge gained about the role of fat in heart disease.

Since fat was considered a major culprit in heart disease, and since heart disease is common in those with diabetes, the recommended intake of carbohydrates has actually increased. Because low-carb eating plans tend to mean consuming more fat, following a strict low-carb style of eating isn't always recommended.

For anyone following a low-carb diet, it's important to understand the difference between healthy fats and unhealthy fats. A low-carb diet that's too high in saturated fats is not a healthy choice for anyone. The USDA recommends that no more than 10% of daily calories come from saturated fats.

Low-carb diets have become synonymous with weight loss, which is also important for many people with diabetes. Choose sources of healthy fats like nuts, fish, and healthy oils over unhealthy sources like processed meat.

Benefits of a Low-Carb Diet for Diabetes

A low-carb diet consists of 20–60 grams per day of carbohydrates, which equals around 80–240 calories (there are 4 calories in 1 carbohydrate). A very low-carb diet is even more restrictive, with carbohydrate intake limited to just 10% of daily calories or less.

Many people with type 1 and type 2 diabetes can benefit from a low-carb diet. A 2015 review looked at almost 100 different studies to determine the advantages of a very low-carb diet for people with these conditions. The authors drew several conclusions, some of which included:

  • A low-carb (very low carb) diet resulted in lower blood sugars.
  • A reduction in blood sugars on a low-carb diet didn't require weight loss, though weight loss is a common result of low-carb diets. (Learn more about weight loss on a low-carb diet).
  • People with type 2 diabetes were sometimes able to reduce the dose of their diabetic medications or eliminate them completely.
  • Changing to a low-carb diet was fairly easy.
  • There were no side effects on the low-carb diet.

The researchers concluded that a low-carb diet should be a first approach in treating type 2 diabetes and is also an effective supplement to medication in the treatment of type 1 diabetes.

Alternatives to a Low-Carb Diet for Diabetes

The Academy of Nutrition and Dietetics recommends a well-balanced diet for people with diabetes and advises consuming a variety of nutrient-dense foods, opting for less fat and salt, and choosing healthy complex carbohydrates over refined carbs. The Academy's recommendations are in alignment with USDA dietary guidelines for a healthy diet.

If your doctor recommends a balanced diet over a low-carb diet, be sure to opt for complex carbs and maintain consistency with your daily carbohydrate intake.

If you're overweight or obese, a healthy, balanced diet combined with regular exercise can help you lose weight.

Following a Low-Carb Diet

If you're interested in following a low-carb diet, talk to your healthcare provider, diabetes educator, or a registered dietician or nutritionist who specializes in medical nutrition therapy for diabetes prior to making any dietary changes.

Since your blood sugars may decrease on a low-carb plan, ask your doctor about any medications you're taking while following a low-carb plan. Switching to a low-carb diet may affect your diabetes and/or blood pressure medications.

Weight loss is likely for many people following a low-carb diet. Many people experience mild side effects like low blood sugar, so it's a good idea to track your blood glucose closely. Keep a journal of your dietary intake to monitor how certain foods are affecting you.

Many people report that the first week or so on a low-carb diet can be challenging. You may experience carb withdrawal in the first few days followed by a "carb crash" occurring roughly 3 to 5 days after you make the switch. Familiarizing yourself with the basics of a low-carb diet can help you avoid some of the common mistakes people make when starting a low-carb plan.

If you're unsure whether a low-carb diet is right for you, ask your doctor for advice. Once you have your physician's approval, you can get started by making your own delicious low-carb recipes at home.

A Word From Verywell

While some health experts argue that a low-carb diet is unnecessary for people with diabetes, there is enough research to suggest that a very low-carb diet may help to reverse the disease.

If you're living with diabetes, always consult your doctor before making any changes to your diet. In general, going on a low-carb diet has few side effects with the exception of low blood sugar. Changes in your blood sugars associated with a low-carb diet could also affect any medications you're taking.

Although low-carb diets for people with diabetes are still up for debate, as research continues to emerge we will likely learn more about the ideal amount of carbohydrates for those living with this condition.

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Article Sources
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