8 I’ll know right away if I have diabetes ThinkstockPhotos-585806934.jpg

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“You might feel tired, sluggish or a little mental slowness, but you may not feel anything,” Dr. Philis-Tsimikas says. “That is why diabetes can sometimes progress for long periods of times, sometimes even years, before it is diagnosed.” Patients can monitor what happens to their blood sugar during exercise, sleep, after eating different kinds of foods, and in different work or leisure environments.  If a certain situation makes their blood sugar go up, they may want to alter this activity to be able to better control it in the future, she adds.