Your blood sugar level, or blood glucose, is the amount of sugar in the blood stream. Pretty basic, right? You eat, you digest carbs with the help of insulin, a hormone released by the pancreas, and then your cells use the resulting glucose for energy. When the pancreas doesn't produce the proper amount of insulin to regulate glucose — a telling sign of diabetes — this is where your blood sugar levels can be too high. Albert Ahn, MD, clinical instructor of internal medicine at NYU Langone, told POPSUGAR that, in terms of regulating your blood sugar, "Unless you have diabetes, your body does this for you." While some people's bodies do this better than others, "Technically speaking, everyone's sugars do stay in a pretty normal, pretty consistent level."
The American Diabetes Association advises that you talk to your doctor about whether or not you should be testing your blood sugar regularly. People with diabetes have to do this using a portable blood glucose meter, or glucometer. "Blood sugar can easily be checked by pricking one's finger for blood with a microneedle called a lancet and applying that blood onto a testing strip which is then placed into a glucometer," Deena Adimoolam, MD, assistant professor of medicine, endocrinology, diabetes, and bone disease at Mount Sinai's Icahn School of Medicine, told POPSUGAR. "People with diabetes or issues with their blood sugars can do this on their own after being trained by their doctor or nurse."
According to the American Diabetes Association, physicians may suggest blood glucose tests for pregnant women, as well as people who are overweight, prone to hypoglycemia (low blood sugar), have a family history of diabetes, or are over the age of 45. Dr. Adimoolam said that those without diabetes or prediabetes do not need to be testing their blood sugar. "If you are concerned with your blood sugar, speak to your doctor to see if any further evaluation is necessary," she said.
What Blood Sugar Level Is Considered Normal?
Note: the definition of "normal" blood sugar is hard to define because it depends on the person and whether or not you're diabetic. We'll be focusing mostly on nondiabetics.
As Dr. Adimoolam told POPSUGAR, "For those people with diabetes, each individual has different goals for their blood sugar values . . . so there is no one perfect number for everyone." She gave us the following parameters for nondiabetics: "Normal blood sugar is considered below 200 mg/dL [milligrams per deciliter] after meals and below 100 mg/dL when fasting." Dangerous levels of blood sugar would be less than 70 mg/dL and more than 200 mg/dL persistently, she said, stressing that we "need to differentiate between what's dangerous for someone who has diabetes and someone who does not have diabetes."
Dr. Ahn gave us a similar range. "If you're someone walking off the street and you're otherwise healthy, and a doctor takes your blood sugar and it's 150 mg/dL," then he'd say you needed further medical attention. In the range between 150-250 mg/dL, "you'll walk around feeling fine, but it's still not safe and I'd consider it high-risk." For people who are nondiabetic, "Your body usually is very, very good at regulating your sugar levels. Within an hour or two of having a big meal, it will come down to the 90-130 mg/dL range."
Symptoms of High and Low Blood Sugar
Both doctors listed symptoms of high blood sugar as increased urination and thirst (especially for ice water), fatigue, and unintentional weight loss. Dr. Adimoolam said women specifically could experience recurrent yeast infections. Symptoms of low blood sugar include headache, dizziness and shakiness, nausea, and slurred speech. The main differentiation between symptoms of low and high blood sugar is that "you don't have this thirst and increased urination," Dr. Ahn explained.
People who have diabetes can develop what Dr. Adimoolam called "hypoglycemia unawareness," where they show no symptoms of low blood sugar because they're using insulin. "Their body is so accustomed to living at low blood sugars that there are no symptoms until the sugar drops to a drastically low number, like less than 50 mg/dL sometimes," she said. "The body thinks that that low blood sugar is normal and no longer releases counter-regulatory hormones to raise the blood sugar until the value drops." She emphasized that this rarely happens to those who do not have diabetes.
How to Maintain Blood Sugar Throughout the Day
"In general, for a healthy person, your body will maintain blood sugars in a normal range throughout the day without much effort on your part due to the presence of hormones and certain neuroregulatory signals," Dr. Adimoolam said. Dr. Ahn agreed. But, both suggested spacing out meals as a way to prevent low blood sugar. "You'll have less peaks and valleys in your sugar levels," Dr. Ahn explained. He also suggested staying away from a high-sugar diet. Be mindful of eating too many sweets, sugar-sweetened beverages, alcohol, "which breaks down into sugar," and all simple carbs that metabolize quickly such as white flours, sugars, rice, and pastas.
Complex carbs, such as fruits and veggies, beans, brown rice, and quinoa have more nutritional value and affect your blood sugar at a slower rate than simple carbs because they take longer to digest. (Bonus: they keep you fuller for longer, too.) If you are eating simple carbs, Dr. Ahn said to make sure you're also consuming fat and protein, which will "help decrease absorption." In addition, Dr. Adimoolam stressed the importance of eating breakfast in the morning, since that's when your blood sugar is lowest.
We focused mainly on blood sugar in nondiabetics. So, for more information on diabetes, click through to diabetes.org and connect with your health care provider. And if you're a diabetic thinking about potentially starting the keto diet, make sure you read this.