A popular low-carb, high-fat diet, often promoted for weight loss, may increase the risk of developing type 2 diabetes by 20%, according to new research. The study emphasizes the importance of maintaining a balanced diet to reduce health risks.
Researchers from Monash and RMIT Universities in Melbourne conducted the study, aiming to explore how a low-carb, high-fat diet impacts the likelihood of developing type 2 diabetes (T2D). Despite public health efforts, T2D rates continue to rise in developed countries. While it’s well-known that poor diet quality is linked to T2D, this study focused on understanding the effects of low-carb diets.
Professor Barbora De Courten from Monash’s Department of Medicine and RMIT’s School of Health and Biomedical Sciences, co-author of the study, explained the common link between high-carb, processed diets and weight gain. “Highly refined carbohydrates increase insulin secretion and resistance, leading to type 2 diabetes,” she said. However, this study shifts focus to low-carb diets, showing they could increase diabetes risk over time, potentially due to higher fat consumption and lower fiber intake.
While prior research has studied low-carb diets for diabetes management, there’s limited and conflicting data on whether such diets increase diabetes risk. Most of the previous studies have been conducted in European and Asian populations, but this study analyzed data from 39,185 Australian adults, aged 40 to 69, as part of the Melbourne Collaborative Cohort Study (MCCS). Participants were followed for up to 17 years after being recruited between 1990 and 1994.
The researchers calculated participants’ low-carbohydrate diet (LCD) scores based on the proportion of calories they consumed from carbs, fats, and proteins. A higher LCD score indicated a diet low in carbs and high in fat and protein.
The findings showed a clear link between LCD scores and diabetes risk. Participants who derived 38% of their energy from carbs had a 20% higher chance of developing T2D than those consuming 55% of their energy from carbs. Obesity played a significant role in this association, explaining 76% of the link, suggesting that a high-fat, low-fiber diet contributes to weight gain, which increases diabetes risk.
“This study shows that low-carbohydrate diets might increase the long-term risk of type 2 diabetes, largely through obesity,” the researchers noted. They emphasized that simply reducing carbohydrates without considering fat and fiber intake may not be effective in preventing diabetes. The Mediterranean diet, which balances carbs, fats, and proteins, was recommended as a better option.
The researchers acknowledged some limitations, such as using 16-year-old self-reported dietary data. However, they pointed out the study’s strengths, including its large cohort size and long follow-up period. They called for further research, particularly clinical trials examining different carb sources in low-carb diets and their effects on diabetes risk.
The study was published in Diabetes & Metabolic Syndrome: Clinical Research & Reviews.
