The factors affecting on estimation of carbohydrate content of meals in carbohydrate counting

The objective of this study was to identify factors affecting on errors in carbohydrate (CHO) content estimation during CHO counting. Thirty-seven type 1 diabetes patients and 22 of their parents and 28 physicians/dieticians were enrolled in this study. CHO counting was counted in "Carb", with 1 Carb defined as 10 g of CHO. To evaluate the accuracy of CHO counting, 80 real-size photographs of cooked meals were presented to the subjects for Carb estimation. Carbs tended to be overestimated for foods containing relatively small amounts of Carbs. On the other hands, Carbs tended to be underestimated for foods with higher than 6 Carbs. Accurate estimation of the Carbs in food containing a large amount of rice was particularly difficult even in the subjects having the CHO counting experience. The Carb contents of high-calorie foods such as meats, fried foods, and desserts tended to be overestimated. This error was smaller in subjects having the CHO counting experience. In conclusion, misunderstanding of high-calorie dishes containing high amounts of CHO was observed in inexperienced subjects, indicating the efficacy of the current methodology of CHO counting. On the other hand it was difficult even for experienced subjects to assess the amount of seasoned rice, suggesting the need for a new methodology for accurate estimation.