In a recent study published in The American Journal of Clinical Nutrition, researchers report that a low-carbohydrate (LC) weight loss plan led to a 74% reduction in postprandial glucose and lower glycemic variability in type 2 diabetics in comparison with those fed a regular low-fat breakfast. 

Study: Impact of a Low-Carbohydrate Compared with Low-Fat Breakfast on Blood Glucose Control in Type 2 Diabetes: A Randomized Trial. Image Credit: Patrycja St / Shutterstock.com

Background

Glycemic variability and postprandial increases in blood glucose are independent risk aspects for heart disease and mortality in individuals with type 2 diabetes (T2D). Likewise, day by day fluctuations in blood glucose levels, including hyper- and hypoglycemia, can increase the danger of diabetes complications.

Heart disease is a major reason behind morbidity and mortality in T2D patients; subsequently, strategies to lower postprandial glucose variations and glycemic variability are crucial. Although a weight loss plan low in carbohydrates is taken into account a potent dietary strategy for higher glucose control, poor dietary adherence can limit the advantages of any such weight loss plan.   

The consumption of carbohydrates causes a rapid increase in blood glucose levels in individuals with T2D, especially within the morning. Due to this fact, one potential and easy solution may very well be to cut back the carbohydrate content of only one meal a day, akin to breakfast, in individuals with diabetes without modifying the macronutrient composition of other meals.

Concerning the study

The current study involved a 12-week, two-site, parallel-arm randomized control trial (RCT) through the coronavirus disease 2019 (COVID-19) pandemic. The target of this study was to find out whether a breakfast low in carbohydrates can improve glucose control in individuals with T2D as in comparison with a low-fat breakfast.

The eligibility criteria included T2D diagnosed by a physician, age between 20 and 79 years, current HbA1c of lower than 69 mmol/L or 8.5%, blood pressure lower than 160/99 mmHg, and a body mass index (BMI) greater than 25 kg/m².

Smokers, individuals using exogenous insulin, those that were on greater than two glucose-lowering medications, those receiving treatment for autoimmune or inflammatory diseases, cancer, and liver or kidney disorders, individuals who were on corticosteroids, hormone substitute therapy (HRT), or anti-inflammatory medications those with allergies or some dietary restrictions, in addition to those that were unable to follow the weight loss plan prescription were excluded from the trial.

Study procedures were explained to the participants, and digital consent was obtained by the research team members through video conference or telephone because of restrictions imposed by the pandemic. The first consequence of the study was changes in HbA1c levels.

Data related to self-reported anthropometrics, glucose monitoring, and dietary information of the participants were gathered. The participants also accomplished the Godin Leisure-Time Exercise Questionnaire to report physical activity.

Study findings

Of the 246 participants who were pre-screened for the study, 127 individuals with T2D satisfied the inclusion criteria. After randomization, 60 individuals were assigned to the LC breakfast group and 61 to the low-fat breakfast group.

The mean age of the participants was 64 years, HbA1c was 7.0, and BMI was 32.3 kg/m², with 53% of the participants being women. While carbohydrate intake was significantly lower within the LC breakfast group, no significant between-group differences were observed in day by day fat or protein intake.

After 12 weeks of consuming an LC breakfast, HbA1c decreased by about 0.3%; nonetheless, the between-group HbA1c difference was only barely significant. No significant differences were observed between LC and low-fat groups when it comes to BMI, weight, or waist circumference. Moreover, no significant between-group differences in physical activity or hunger and satiety were observed through the study period.

Within the LC group, total self-reported day by day energy was -242 kcal, and carbohydrate intake was -73 g. Each values were lower as in comparison with the low-fat group; nonetheless, their significance was not clear. Parameters akin to glycemic variability, mean and maximum glucose, standard deviation, time above range, and area under the curve were significantly lower as in comparison with the low-fat group.

Conclusions

There’s extensive evidence to suggest that carbohydrate restriction improves glycemic control in individuals with T2D. Although the first consequence of the present study was not significantly different between the 2 groups, many other glucose monitoring metrics were higher within the LC breakfast group as in comparison with the low-fat breakfast group through the monitoring periods. Longer and more controlled studies may help result in significant HbA1c reductions within the LC group as in comparison with the low-fat group.

The present study also demonstrated high compliance with breakfast interventions, despite being a distant study with minimal supervision. High feasibility of the LC breakfast over the 12-week study period was also observed, thus indicating that moderate carbohydrate restrictions are easier for people to comply with as in comparison with severe carbohydrate restrictions.

Overall, the study findings suggest that consuming an LC breakfast may very well be an easy and simpler dietary strategy that helps reduce overall carbohydrate and energy intake and improve multiple glucose monitoring variables in individuals with T2D as in comparison with consuming a low-fat breakfast.