Blood sugar (glucose) levels are represented in either the UK or US standard units. UK Standard uses mmol/L, while US Standard uses mg/dL. Both sets of units measure concentration of glucose in our blood, and represents blood sugar level for diebetic patients.
Formula 1 mg/dL = 18 x mmol/L
We often use blood sugar test to diagnose dibetes, and there are 2 standards used globally. The USA standard uses mg/dL, and the "fasting" (before meal) blood sugar reading of 99mg/dL or lower is determined normal. A blood sugar levell of 100 ~ 125 mg/dL indicates prediabetes, and anything over 125 mg/dL indicates you're diabetes.