Low-carb diet may reduce medication dependence for type 2 diabetics, new study reveals

Type 2 diabetes (T2D) patients suffer from a compromised beta-cell response to blood sugar, in part due to the consumption of too many carbohydrates. A new study suggests that a diet plan low in carbs may address this issue, allowing patients to better manage the disease and even potentially discontinue medications.

“A low carbohydrate diet does provide the opportunity to improve beta-cell function without the need for medication use or weight loss, which may be more appealing for some persons with T2D,” Dr. Barbara Gower, lead study author and a professor at the Department of Nutrition Sciences of the University of Alabama Birmingham, US, tells Nutrition Insight.

Beta cells are endocrine cells in the pancreas that produce and release insulin. Beta-cell failure or insufficiency combined with insulin resistance is responsible for the development and progression of T2D.

“Treatment of T2D optimally involves lifestyle interventions featuring healthy meal patterns in conjunction with medical therapy,” continues Gower.

“The low-carbohydrate diet can be a sustainable solution, especially with the help of a dietitian who is familiar with the low-carb lifestyle. It is possible to substitute a lot of common carb-containing foods with low-carb alternatives.”

A healthy low-carb diet

For this study, published in the Journal of Clinical Endocrinology & Metabolism, the research team gathered data from 57 adults with T2D, half of which went on a low-carbohydrate diet and half on a high-carbohydrate diet. The team then examined their beta-cell function and insulin secretion at baseline and after 12 weeks.

“Adherence to a low-carbohydrate diet is a lifestyle approach that is based on a whole-foods diet, composed primarily of meat, vegetables, eggs and dairy, while minimizing the consumption of processed foods,” Gower details.

All participants received meals as part of the research. Those on the carbohydrate-restricted diet were given 9% carbohydrates and 65% fat, while those on a high-carbohydrate diet consumed 55% carbohydrates and 20% fat in their meals.

“In general, the patients loved the low-carb diet. We provided groceries, recipes and menus, along with regular meetings with a dietitian. This clearly demonstrates that the low-carb lifestyle can be sustainable as long as one has training and can plan ahead (i.e., create meal plans and buy the groceries),” she adds.

The study found that those on a low-carbohydrate diet improved their acute and maximal beta-cell responses by two-fold and by 22%, respectively.

Challenges and opportunities 

Gower addresses some of the perceived challenges or concerns that some might associate with low-carb diets.

“Although total cholesterol goes up with the low-carb diet, it is the high density (‘good’ cholesterol) component that increases. Thus, it is not harmful. Triglycerides drop dramatically when adhering to a low-carb diet, and this decreases the risk for heart disease,” she explains.

“This type of diet approach has been shown in similar contexts (e.g., the Mediterranean diet) to be beneficial to overall health. There are no adverse effects, as long as hydration is maintained, which can be accomplished with electrolytes when necessary.”

Further discussing if the study participants faced any issues following the diet, Gower says: “Eating out at restaurants and fast food places is possible, but requires omitting the carbs, which might be perceived as increasing cost (same cost but less food).”

“For example, getting a hamburger without the bun or swapping the fries for a salad. It is important to ensure adequate energy intake. Individuals might have to add a healthy dose of olive oil to the salad or a few salad add-ins with protein and fat (e.g., hard-cooked eggs or cheese or nuts).”  

She says that the low-carbohydrate diet is “very satisfying” because it often has a high-fat content, “which leads to a feeling of fullness and reduced cravings for sugar.”

“Our patients often tell us that they no longer crave unhealthy foods when they eat low-carb because their meals and snacks are rich and satisfying.”

Effective without weight loss

One of the most notable aspects of this study is that the beta-cell response improved through the low-carb diet alone.

“Previous studies that have shown the return of a beta-cell function (e.g., through bariatric surgery or very-low-calorie diets) have involved dramatic weight loss, and such approaches are difficult, expensive or not sustainable for all individuals with T2D,” shares Gower.

“There are also no conventional drug therapies that result in improved beta-cell function. There has been very little research with exercise alone in the absence of weight loss, with beta-cell function as an outcome, so we do not know the answer to that.”

In this regard, she states that the results of this study are the first to show that a low-carbohydrate diet can improve beta-cell function, particularly without intentional weight loss, which may be a more appealing approach in some persons with T2D.

Study implications 

The scientist asserts that the research she led should not be interpreted to mean that a low-carbohydrate diet can replace medical therapy in those who need it, especially patients at risk of cardiovascular disease, heart failure, chronic kidney disease or when medications are needed to achieve hemoglobin A1c (HbA1c) targets. 

“However, a low-carb diet could be considered as a component of lifestyle therapy that could contribute to better glycemic control as a consequence of improved beta-cell function. Individuals with diabetes can be counseled to eat carb-free and potentially reduce or eliminate their medication, but it is important to work closely with their physician and a dietitian,” Gower details.

“Many medications have undesirable side effects, which can be reduced or eliminated by using nutrition therapy to treat the disease. However, for patients who use glucose-lowering medication, careful monitoring of blood glucose is required initially when transitioning to a low-carb diet, as continued use of medication can result in low blood sugar (hypoglycemia).”

She warns that individuals may want to gradually decrease their medication dose as they transition to a low-carb lifestyle while carefully monitoring blood glucose. 

The next steps 

In the future, Gower would like to find out more about how different patient populations respond to precision nutrition in the form of a low-carb diet prescription.

“T2D is a heterogeneous disease. Some patients have a genetic factor that leads to early beta-cell decline, while some primarily have insulin resistance. Thus, these two types of individuals might respond differently to a low-carb diet,” she says.

“Participants in our study were adults with ‘early’ T2D (with a diagnosis of less than ten years), which has been associated with a greater potential to restore beta-cell function.”

Long-term patients on insulin can manage their disease quite effectively with a low-carb diet, she explains, while adding that they are unlikely to show improvement in beta-cell function.  “We would also like to know more about how the diet affects glucose control in individuals who have had T2D for more than ten years.”

“Additionally, a longer duration study, while the patients remain off medications but continue to consume a low-carb diet, would determine whether this diet could eliminate or reduce the need for diabetes medications to maintain a HbA1c target.”  

The team further sets out to better understand the mechanisms by which a low-carb diet acts on target organs. “In particular, research on the effects of a low-carb diet on hepatic metabolism is limited and needs to be done. Much of the blood sugar in T2D is generated by the liver (vs what is consumed as food).”

“Thus, we need to determine if a low-carb diet decreases hepatic glucose production, in addition to how the diet affects the many metabolic pathways that are perturbed in T2D,” Gower explains.