Diabetes is diagnosed after an average of 10–12 years of diabetic development. Strict glycemic control in diabetic patients promotes the normalization of blood glucose and reduces cardiovascular diseases (CVDs) and diabetic complications. Therefore, early diagnosis in non-aware individuals is very important.

Clinical indices and nutrient intakes in Korean diabetic adults aged 19–64 years were examined according to the awareness of diabetes, using 2012 and 2013 Korea National Health and Nutrition Examination Survey (KNHANES) data. The aware group was defined as individuals who were aware of having diabetes from diagnosis by physician before the survey and the non-aware group as individuals who were not aware of having diabetes.

The average age was higher in the aware group compared to the non-aware group in both men (P = 0.002) and women ( P = 0.004). The prevalences of hypertension and dyslipidemia were not different between the two groups, but the diagnosis rate was significantly lower in the non-aware group. In the non-aware group, total and LDL-cholesterol were significantly higher ( P < 0.001), the risk for total cholesterol over 240 mg/dL was 3.4 times (95% CI: 1.58–7.52) higher ( P = 0.002) and the risk for LDL-cholesterol over 160 mg/dL was 4.59 times (95% CI: 2.07–10.17) higher ( P < 0.001). The calorie intake of the female non-aware group was significantly higher compared to the female aware group ( P = 0.033).

The results suggested that the recommendation of screening test is necessary even for young adults. Studies on the methodology for early diagnosis of diabetes are also needed.