Plain language summary
Dietary intervention is a strategy to manage diabetes mellitus, as it can reduce the burden on islet cells and thus improve blood glucose levels, lipid profiles, and cognitive status. The aim of the study was to find out the effectiveness of the ‘six-point formula’ and the effects of a low-fat diet and low-carbohydrate diet on hyperglycaemia. The study is a prospective, single-blind randomized controlled trial which recruited 56 participants with type 2 diabetes mellitus. The participants were randomly allocated to receive either a low-fat diet or a low-carbohydrate diet. Results show that HbA1c levels (the average blood glucose levels in the last 2 – 3 months) in low-carbohydrate diet decreased significantly compared to the low-fat diet. The body mass index and the total cholesterol levels of the participants following the low-carbohydrate diet also decreased. Authors conclude that a low-carbohydrate diet can improve blood glucose, regulate blood lipids, reduce body mass index and decrease insulin doses more than a low-fat diet in Chinese patients with type 2 diabetes mellitus.
OBJECTIVE In China, a low-fat diet (LFD) is mainly recommended to help improve blood glucose levels in patients with type 2 diabetes mellitus (T2DM). However, a low-carbohydrate diet (LCD) has been shown to be effective in improving blood glucose levels in America and England. A few studies, primarily randomized controlled trials, have been reported in China as well. METHOD Firstly, we designed two 'six-point formula' methods, which met the requirements of LCD and LFD, respectively. Fifty-six T2DM patients were recruited and randomly allocated to the LCD group (n = 28) and the LFD group (n = 28). The LCD group received education about LCD's six-point formula, while the LFD group received education about LFD's six-point formula. The follow-up time was three months. The indicators for glycemic control and other metabolic parameters were collected and compared between the two groups. RESULTS Forty-nine patients completed the study. The proportions of calories from three macronutrients the patients consumed met the requirements of LCD and LFD. Compared to the LFD group, there was a greater decrease in HbA1c level in the LCD group (-0.63% vs. -0.31%, p < 0.05). The dosages of insulin and fasting blood glucoses (FBG) in the third month were lower than those at baseline in both groups. Compared with baseline values, body mass index (BMI) and total cholesterol (TC) in the LCD group were significantly reduced in the third month (p < 0.05); however, there were no statistically significant differences in the LFD group. CONCLUSIONS LCD can improve blood glucose more than LFD in Chinese patients with T2DM. It can also regulate blood lipid, reduce BMI, and decrease insulin dose in patients with T2DM. In addition, the six-point formula is feasible, easily operable, and a practical educational diet for Chinese patients with T2DM.