Can Carbohydrate Restriction Reduce the Need for Medication in Type 2 Diabetes?

A New Study

Type 2 diabetes (T2D) patients may preserve beta-cell function with a low-carbohydrate diet, allowing some to reach blood glucose targets without medication, according to a new study.

These results came from a 12-week study involving 57 patients with T2D who were not using insulin. Participants were assigned a low-carbohydrate diet (9% carbohydrate) or a high-carbohydrate diet (55% carbohydrate). C-peptide levels were significantly higher in those following the low-carbohydrate diet than in those following the high-carbohydrate diet. The findings were published on October 22, 2024 in The Journal of Clinical Endocrinology & Metabolism.

Carbohydrate Restriction and Beta-Cell Function

Marian L. Yurchishin of the University of Alabama, who led the research, said this study was the first to show that carbohydrate restriction can improve beta-cell function. It also showed a greater increase in insulin secretion with carbohydrate restriction among African American patients than among European American patients. According to Yurchishin, carbohydrate restriction could offer an opportunity to improve beta-cell function without medication and may be a more effective approach particularly for patients of African ancestry.

However, Yurchishin emphasized that this research does not mean carbohydrate restriction can replace medication, particularly in patients at risk of cardiovascular disease, heart failure, or chronic kidney disease, for whom particular caution is needed.

Can It Be Applied in Real Life?

The study's striking findings may raise some concerns. First, this type of low-carbohydrate diet may not be sustainable over the long term because of its high fat content (65%). Essentially a ketogenic diet, this approach does not sufficiently emphasize consumption of heart-healthy unsaturated fats. In addition, home delivery of participants' food and instructions on its preparation are considered factors limiting applicability in real-life conditions.

Improvement in Beta-Cell Function

Participants were either African American or European American and had all been diagnosed with T2D within the preceding 10 years. Calorie intake was similar in the two diet groups, but all medications were discontinued 1-2 weeks before the study.

At the end of 12 weeks, C-peptide levels in the low-carbohydrate group were twice as high as in the high-carbohydrate group. This difference was particularly significant among African American participants (a 110% increase). The difference was not seen among European American participants. Carbohydrate restriction also increased the beta-cell response by 22%.

Differences Between Racial Groups

The researchers note that the pathophysiology of T2D may vary between racial groups because of genetic factors and environmental interactions. Obesity and insulin resistance may play a smaller role in the development of T2D among African Americans, while beta-cell dysfunction may be more decisive. They emphasize the need for further investigation of these biological differences.

Although Yurchishin and colleagues suggested that carbohydrate restriction might offer a medication-free treatment option for some patients, they noted that sustaining the diet could be difficult and that it might not suit everyone.

Conclusion

Although this study suggests that carbohydrate restriction has the potential to reduce medication use in T2D, experts stress that the approach may not be sustainable for everyone and that medication should not be disregarded. The protective role of medications is particularly important for patients with cardiovascular risk.