High blood sugar (also called hyperglycemia or high blood glucose) is when there’s too much glucose (sugar) in your bloodstream, typically because your body isn’t using or producing insulin as well as it should. Insulin is a hormone that helps control blood sugar levels.
Normally, your pancreas releases insulin when your blood sugar, or blood glucose, gets high – after a meal, for example. This tells your body to absorb glucose until levels get back to normal.
But if you have diabetes, your body doesn’t make insulin (type 1 diabetes) or doesn’t respond to it normally (type 2 diabetes). That can leave your blood sugar too high for too long. Over time, this can damage nerves and blood vessels and lead to heart disease and other problems.
How much sugar in the blood is too much? And why is high blood glucose so bad for you? Here’s a look at how your levels affect your health.
What Are Normal Blood Sugar Levels?
Healthy blood sugar levels are less than 100 milligrams per deciliter (mg/dL) after not eating (fasting) for at least 8 hours. And they’re less than 140 mg/dL 2 hours after eating.
During the day, levels tend to be at their lowest just before meals. For most people without diabetes, blood sugar levels before meals hover around 70 to 80 mg/dL. For some people, 60 is normal; for others, 90.
What’s a low sugar level? It varies widely, too. Many people’s glucose won’t ever fall below 60, even when they fast for a long time. When you diet or fast, the liver keeps your levels normal by turning fat and muscle into sugar. A few people’s levels may fall somewhat lower.
Normal blood sugar levels
- While fasting, your blood sugar levels should be between 72 and 99 mg/dL
- Two hours after eating, your levels should be no higher than 140 mg/dL
Symptoms of High Blood Sugar
Symptoms of high blood sugar depend on whether you’re in the early or later stages of the condition:
- Early symptoms. You’ll feel thirstier, pee more often, get headaches, and have blurred vision.
- Long-term symptoms. If you’ve had hyperglycemia for a while, you may feel extremely tired (fatigued), lose weight, get skin or vaginal yeast infections, and have trouble healing from cuts or sores.
People with prediabetes, or a blood sugar level that’s higher than normal, usually don’t have any signs or symptoms of the illness.
- Related:Where to Get Healthy Carbs
Recent Articles
The ring you choose reflects your personality.
Pecan Cream Pie
Cases are on the rise
My 9-year-old daughter baked 300 Easter cookies for the homeless — the next morning, a stranger showed up at our door with a briefcase full of cash. My daughter, Ashley, has always had a heart too big for her chest. Since my wife died, we’ve barely been making ends meet. We spent everything we had trying to save her from cancer. But when Easter came this year, Ashley told me she’d been saving up her own money to buy ingredients. “For the homeless,” she said. Her mom used to be one of them. She was thrown out by her parents when they found out she was pregnant with Ashley. When I met her, she had nothing — but she had the brightest smile and the sharpest mind I had ever seen. I fell in love with her. I took her and Ashley in. And from that moment on, Ashley became my daughter in every way that matters. So when Ashley said she wanted to help people like her mom once was… I didn’t stop her. For three nights straight, after school and homework, she baked. Her little hands worked nonstop. She found her mom’s old cookie recipe. She rolled every piece of dough herself. She decorated every cookie. She made three hundred cookies. On Easter, she handed them out one by one. She looked people in the eyes. She wished them a Happy Easter. Some of them smiled. Some of them cried. I stood there thinking it was the proudest moment of my life. I thought that was the end of it. The next morning, I was washing a mountain of dishes when the doorbell rang. I opened the door. An older man stood there in a worn-out suit, holding a scratched aluminum briefcase. His eyes were locked on Ashley. Before I could ask anything, he set the case down and opened it. I froze. Stacks of hundred-dollar bills — more money than I had ever seen in my life. “I saw what your daughter did yesterday,” he said, his voice shaking. “I want to give all of this to her.” My heart skipped. Then he added: “But you have to agree to ONE CONDITION.” My chest tightened. “What condition?” I asked. He stepped closer. He lowered his voice. And what he asked for in return made my blood run cold.
