1. You’ve noticed unpleasant skin changes Dark, velvety patches in the folds of skin, usually on the back of the neck, elbows, or knuckles, are often an early warning sign of too-high blood sugar levels. Although genetics or hormonal conditions can cause the skin disorder, called acanthosis nigricans, “when I notice the patches, the first thing I do is test my patient’s blood sugar,” says Sanjiv Saini, MD, a dermatologist in Edgewater, Maryland. “High insulin levels promote the growth of skin cells, and melanin, a pigment in these cells, makes the patches dark.” The test may show that the patient already has diabetes, but, more likely, it will detect higher-than-normal blood sugar levels, suggesting the patient is on the way to developing the disease, explains Saini. Losing weight—as little as 10 pounds—will likely lower blood sugar levels and help the condition clear up. Otherwise, he says a dermatologist can treat it with laser therapy or topical retina A.
2. Your vision improved out of nowhere
Sorry, suddenly being able to ditch your glasses probably isn’t good news: “You’ll often read that blurry vision is as a diabetes symptom when, in fact, vision can change for better or worse,” says Howard Baum, MD, an assistant professor of medicine in the diabetes division at Vanderbilt University. “I’ve had patients tell me that their vision has improved when their blood sugars were elevated, and then after they start treating their diabetes, they needed their glasses again.” What gives? Diabetes causes fluid levels in the body to shift around, including inside your eyes, which leads to the erratic eyesight.
3. You have unrelenting itchiness Think it’s silly to mention scratchy skin to your doctor? Not so. Diabetes impairs blood circulation, which can lead to dryness and itchiness. “Some of my newly diagnosed diabetes patients mention they’re itchy on their extremities—the hands, lower legs, and feet—so it’s something doctors should consider in conjunction with other symptoms,” says Baum. If regular use of a moisturizer doesn’t fix the itch, bring it up at your next appointment.
4. Your hearing isn’t what it used to be
If you find yourself cranking the volume on the TV or you can’t get through a conversation without asking people to repeat themselves, tell your doctor you need a blood sugar test. One study by the National Institute of Health suggested hearing loss could be an early warning sign of diabetes: People with higher than normal blood sugar who didn’t yet meet the criteria for diabetes were 30% more likely to have hearing damage than those with healthy glucose levels. The researchers believe that diabetes damages the blood vessels and nerves of the inner ear, leading to sub-par hearing.5. You snore like a chainsaw “About half of type 2 diabetics have sleep-disordered breathing,” says Osama Hamdy, MD, director of inpatient diabetes management at Joslin Diabetes Center in Boston. So if you’re diagnosed with the condition—characterized by loud snoring and daytime sleepiness—it’s a good bet to get your blood sugar levels checked, too. One recent Canadian study showed that 23% of patients diagnosed with mild or moderate obstructivesleep apnea, a common sleep disorder, went on to develop diabetes within 5½ years. The connection isn’t completely understood, but there’s one important link between the two: Patients with sleep-disordered breathing tend to release stress hormones during sleep, which can raise blood sugar levels.