If you get a physical every year, chances are that your doctor orders a blood test that will tell you, among other things, if your blood sugar level is “normal.” If it’s not, you may have diabetes, or be at risk for it in coming years. But what’s this strange thing called “normal” anyway?
There’s two main ways to measure blood glucose, depending on where you’re located.
If you’re in Europe:
In Europe, blood sugar is measured using millimoles per litre. A “normal” blood glucose level comes in at around 4 – 7 mmol/L or 4 – 8 mmol/L for a child with Type 1 diabetes before meals.
Two hours after a meal, a normal blood sugar range should be under 9 mmol/L for people with T1D. For T2D, the upper range is slightly lower at 8.5 mmol/L. You can find additional information on the Diabetes UK website.
If you’re in the US:
The clinical definition puts “normal” blood glucose at 70-120 mg/dL (milligrams per decilitre) if you’ve fasted eight to twelve hours, or 70-160 mg/dL if you did not fast. That probably makes perfect sense if you have “M.D.” after your name. If you don’t, here’s the translation: 70 to 120 milligrams per deciliter. Clear as … uh…. blood, right? Don’t worry, it’s just the mathematics of measuring density.
Here’s an easier way to remember ideal levels, courtesy of doctor Mehmet Oz: Optimal blood glucose is less than 100 after a fast, less than 125 if you weren’t fasting.
But even then, remember, glucose levels are like the tide, constantly ebbing and flowing, depending on when – and what – we last ate.
What is blood glucose anyway? Blood glucose means the same thing as blood sugar. But ironically enough, the amount of sugars coursing through our blood is not based on our intake of sugar, but how many carbohydrates we consume, and what kinds. But don’t get excited; that’s not license to head to the pastry shop.
Carbs can be “high-glycemic” or “low-glycemic,” depending on how fast your body breaks them down. High-glycemic foods enter the bloodstream rapidly. They’re the bad guys. Think doughnuts, white bread, potatoes.
Low-glycemic foods are the good guys, the carbs in white suits that amble along peacefully, keeping order, and giving your body what it needs precisely when it needs it. Think apples, oatmeal, whole-wheat bread. But, even they need help from insulin, the hormone that allows glucose to penetrate the bloodstream so it can be carried to all the body’s cells.
Type 1 — or insulin-dependent – diabetes develops when the pancreas fails to produce enough insulin, and eventually doesn’t produce any at all. Without the gatekeeping effect of insulin, blood sugar backs up and glucose levels get wildly out-of-whack. They can spiral high (hyperglycemia) or low (hypoglycemia), and each milligram away from the normal range exacerbates the symptoms.
Signs of hyperglycemia include:
- Blurred vision
- Thirst
- Increased urination
- Fatigue
- Headache
- Shortness of breath
- And, if untreated, confusion and coma.
Signs of hypoglycemia also include:
- Blurred vision
- Confusion
- Heart palpitations
- Shakiness
- Extreme hunger
- Dizziness
- Weakness
We don’t want to go there. That’s why doctors recommend that everyone – whether they have diabetes or not – keep an eye on their blood glucose levels, and have them checked every few years. And people living with diabetes, of course, check ours constantly, as part of the “new normal” that develops after a diabetes diagnosis. That’s okay …. When it comes to blood glucose, any kind of normal is good.