The signs and symptoms of elevated blood sugar are easy to ignore, mistake or miss. This is especially true for type 2 diabetes, which can go undiagnosed for many years. “Undiagnosed diabetes is more common than many people think,” says Mary Ellen Phipps, M.P.H., RDN, LD, author of The Easy Diabetes Cookbook. “According to the CDC, 8.7 million adults meet the diagnostic criteria for diabetes, but don’t know they have it. That's 3.4% of the U.S. adult population.”
Why are so many people in the dark? “Many people with mild to moderately high blood sugar, especially in prediabetes or early type 2 diabetes, may have no noticeable symptoms at all,” says Jackie Topol, M.S., RD, CDN, a New York City-based registered dietitian and prediabetes expert. Plus, high blood sugar develops gradually. During early stages, it’s often not severe enough to be recognized by classic symptoms.
The good news is that early intervention can help, says Phipps. Whether you have a family history of high blood sugar or just want to protect yourself, here are the symptoms you want to be aware of.
View Recipe
1. You’re Always Thirsty and Need to Pee
Is your thirst unquenchable? And are you making more frequent trips to the bathroom? With high blood sugar these symptoms often go hand in hand. The reason: “Excess sugar in the blood results in the kidneys working harder to get rid of it,” says Maria Elena Fraga, RD, CDCES, CDN, a registered dietitian with Mount Sinai New York-Concierge Care. “The kidneys draw in water from your tissues to dilute the glucose so it can be excreted via the urine, resulting in more frequent trips to the bathroom.” That loss of water and electrolytes increases thirst, so you continue to drink more. If you’re drinking extra sugary beverages such as juice, sports drinks and soda, your blood sugar can rise even higher.
2. You’re Hungry All the Time
“Your body converts the food you eat into glucose, later used by your cells for energy,” says Fraga. However, sometimes, that glucose is unable to enter your cells. This can happen because your body cannot make enough of the hormone insulin needed to shuttle glucose into your cells. Or the insulin that it makes is not being used efficiently. The result? “The inability to use glucose causes a lack of energy, which can make you hungrier than usual,” says Fraga.
Excessive hunger accompanied by weight loss can be an indication of diabetes, especially type 1 diabetes. If you’re eating enough but are still constantly hungry and are also losing weight, an evaluation by a medical professional is critical.
3. Your Vision Is Blurry
High blood sugar can affect the small vessels of the eyes, resulting in blurry vision that comes and goes, sometimes long before a diabetes diagnosis is made. Over time, this can damage the retina of your eye, resulting in a condition known as diabetic retinopathy., That’s why the American Diabetes Association recommends that all people diagnosed with type 2 diabetes receive a dilated eye exam shortly after diagnosis.
4. You’re Always Tired
Remember how your cells need glucose for fuel? A lack of insulin, insulin resistance or a combination of both can prevent cells from taking in glucose from the bloodstream for energy. Without the proper fuel, you can feel very tired and fatigued.
5. You’re Having Frequent Urinary Tract Infections
Research shows that nearly 40% of people living with diabetes experience urinary tract infections (UTIs). That’s because the body works to get rid of excess blood sugar by increasing urine output. While that may help lower sugar in the bloodstream, it can also lead to increased bacterial growth that can cause UTIs, says Fraga.
6. You Develop Dark Spots and Skin Tags
Dark velvety patches in crevices of the skin, such as the neck folds, armpits, fingers and groin, could be an indication of a diabetes-related condition called acanthosis nigricans. It is caused by high insulin levels, “which can be an early sign of prediabetes, diabetes [or] insulin resistance,” says Fraga. However, those aren’t the only skin issues linked to high blood sugar. Skin tags, dermatitis, bacterial and fungal infections and dry, itchy skin can also be hidden signs of high blood sugar.
7. You Have Other Strange Symptoms
Not everyone will experience the same symptoms, and some are more common than others. “Hair loss and dry skin, nausea, wounds that won’t heal, tingling in the fingers and toes, and dry mouth are other symptoms of high blood sugar,” says Phipps. So are sexual issues like loss of libido or erectile dysfunction in men and vaginal dryness in women.
Causes of High Blood Sugar
Elevated blood sugar occurs when sugar in the form of glucose accumulates in your blood, says Topol. We get glucose from carbohydrate-containing foods such as bread, rice, pasta, fruits and sugary foods. “After digestion, [their] glucose enters the blood and is used by the body for energy,” she explains. “Insulin, a hormone made by the pancreas, assists in moving glucose from the blood into the cells. If a person doesn’t make insulin or can’t use it properly (as in insulin resistance), sugar stays in the bloodstream instead of being used for energy.” Over time, chronically elevated blood sugar can lead to prediabetes, type 2 diabetes and other health issues, she says.
There are some risk factors that can increase the likelihood of developing type 2 diabetes or prediabetes:
- Are over age 45
- Have a family history of diabetes
- Have had gestational diabetes or delivered a baby weighing 9 or more pounds
- Are of Asian American, African American, Native American, Hispanic, Latino or Pacific Island descent
However, there are some risk factors you can control like:
- Maintaining a healthy body weight
- Being physically active
- Avoiding smoking
- Managing high blood pressure, if you have it
Fortunately, early detection and intervention can prevent diabetes, delay a diabetes diagnosis and reduce the risk of complications. In some instances, it may even be possible to reverse diabetes. “People are more likely to achieve diabetes remission if their diagnosis was within the last two years as opposed to longer,” says Phipps. If you suspect you have diabetes or prediabetes, don’t wait. Speak with your health care provider, who can recommend a quick, easy blood test to find out for sure.
These 8 Things Could Increase Your Prediabetes Risk, According to Experts
The Bottom Line
Elevated blood sugar is not always accompanied by symptoms. However, there are some sneaky signs to be aware of. If you’re always thirsty, hungry, tired and constantly need to pee, high blood sugar could be the culprit. There are other hidden signs, like blurry vision, frequent urinary tract infections and strange skin developments like dark patches or skin tags.
If you have high blood sugar, targeted lifestyle changes—like a blood sugar-friendly diet, exercise and weight loss, if indicated—can make a meaningful difference. The first and most impactful change you can make is to assess your eating habits. If you need assistance planning meals specific to your food preferences and culture or discovering which foods work best for your body, consider meeting with a registered dietitian. These nutrition experts can provide personalized guidance on the best ways to structure your meals and snacks for better blood sugar and overall health.
