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

How a very 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 an ultra-low carbohydrate may be able to reverse diabetes. Let's take a look at the role of carbohydrates in a healthy diet for people with diabetes, and what studies to date have been telling us 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 carbohydrates 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 Dietary Guidelines for Americans, 2015-2020 recommends you get about half of your daily calories from nutrient-dense carbohydrate sources—around 900 to 1,300 calories in a 2,000 calorie diet. This translates to roughly 250 grams of healthy carbohydrates per day, but it depends on your size, sex, and how active you are.

History of Carbohydrates in a Diabetic Diet

For people with diabetes, the amount of recommended daily intake of carbohydrates has a roller coaster history and remains somewhat as 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 and when we began to learn 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 people with diabetes, the recommended intake of carbohydrates actually increased. Since a low-carb diet means more fat, it was not recommended. Now we are learning that the amount of fat in our diet is much less important than we once thought. In addition, eating a low-carb diet became the new way to achieve weight loss, also important with diabetes.

Next we'll take a look at the current arguments both for and against a low-carb diet for people with diabetes.

Argument Against a Low-Carb Diet for Diabetes

The Academy of Nutrition and Dietetics advises those with diabetes to eat a variety of foods, consuming less fat, and choosing healthy carbohydrates for a balanced diet. Opt for complex carbohydrates and maintain consistency with your daily carbohydrate intake. And if you're overweight or obese, a healthy diet and regular exercise can help you lose weight.

Argument for Low-Carb Diet for Diabetes

It's important to acknowledge how a low-carb diet can potentially affect people living with diabetes. A low carb diet consists of 20 to 60 grams per day of carbohydrates, which equals around 80 to 240 calories within the standard 2,000 calorie diet. A very low-carb diet is even more restrictive, with carbohydrate intake limited to only 10% of daily calories or less.

A 2015 review looked at almost 100 studies to see if there were any advantages to eating a very low-carb diet. 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.

Overall, researchers concluded that a low-carb diet should be a first approach in treating type 2 diabetes.

There are arguments both for and against their claims, but for those who find this information compelling, it's not just diabetes and lipids that might improve. There are several health benefits of a low-carb diet that have been found in medical studies ranging from improvements in conditions ranging from irritable bowel syndrome to acne.

If You Choose to Adopt a Low-Carb Diet

If you're interested in following a low-carb diet it's important to talk to your health care provider, diabetes educator, or a dietician or nutritionist who specializes in medical nutrition therapy for diabetes prior making any dietary changes. Since your blood sugars may very well decrease, talk with your doctor about medications and low carb diets. In addition to affecting your diabetes medications, changing to a low-carb diet may affect your high blood pressure medications as well.

Since the major "side effects" of a low-carb diet are weight loss and low blood sugar, it's important to monitor your blood glucose very closely and keep a journal of dietary intake alongside your readings at first. The the first week on a low carb diet can be challenging, with people complaining of both carb withdrawal in the first few days followed by a "carb crash" occurring roughly 3 to 5 days after your switch.

Take a moment to learn the basics of a low-carb diet as well as common mistakes people make when starting a low-carb diet.

After you talk with your doctor and learn about low-carb diets, here are some low-carb dinner recipes to get you started.

Bottom Line on a Low-Carb Diet for Diabetes

In general, it's been thought that a low-carb diet is unnecessary for people with diabetes, though some research suggests that a very low-carb diet may sometimes even reverse the disease. Before making any changes, it's important to talk with your doctor. In general, going on a low-carb diet has few side effects with the exception of weight loss, but doing so may result in changes in your blood sugars which could affect the medications you are taking.

As research continues to emerge, it's likely we will learn more about the ideal amount of daily carbohydrate intake for the diabetic diet in the near future.

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Article Sources
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