For most adults with type 2 diabetes, the target fasting blood sugar is 80 to 130 mg/dL, and blood sugar should stay below 180 mg/dL two hours after eating. These are management targets, not “normal” in the way a non-diabetic body regulates glucose. A person without diabetes typically stays below 100 mg/dL fasting and rarely exceeds 140 mg/dL after meals. Understanding the gap between those ranges, and where your own numbers should fall, is the core of daily blood sugar management.
Fasting Blood Sugar Targets
Fasting blood sugar is measured first thing in the morning, before eating or drinking anything other than water. In a person without diabetes, a normal fasting reading is below 100 mg/dL. Readings between 100 and 125 mg/dL fall into the prediabetes range, and 126 mg/dL or higher on two separate tests is the threshold used to diagnose diabetes.
Once you have a type 2 diagnosis, the goal shifts from “normal” to “well-managed.” Most guidelines recommend keeping fasting glucose between 80 and 130 mg/dL. That range balances the long-term risks of high blood sugar (nerve damage, kidney problems, cardiovascular disease) against the short-term danger of dropping too low.
After-Meal Blood Sugar
Blood sugar peaks about one to two hours after the start of a meal. The CDC recommends that people with diabetes aim for a reading below 180 mg/dL at the two-hour mark. Some clinicians set a tighter target of under 140 mg/dL for people who can reach it without frequent lows, but 180 mg/dL is the widely accepted ceiling.
What you eat, how much, and how quickly your body responds to insulin all affect that post-meal spike. Meals heavy in refined carbohydrates tend to push the number higher and faster than meals built around protein, fiber, and healthy fats. Tracking your readings after different meals can reveal patterns that are more useful than any single number.
A1C: The Bigger Picture
While finger-stick readings capture a single moment, the A1C test reflects your average blood sugar over roughly two to three months. It measures the percentage of your red blood cells that have glucose attached to them. An A1C below 5.7% is considered normal, 5.7% to 6.4% indicates prediabetes, and 6.5% or higher confirms diabetes.
For most adults already living with type 2 diabetes, the American Diabetes Association sets a management goal of below 7%. That roughly translates to an average blood sugar of about 154 mg/dL. Some people aim lower, and some are given a higher target depending on their age, overall health, and risk of low blood sugar episodes. The key point: A1C is not one-size-fits-all, and your target may change over time as your health evolves.
Time in Range
If you use a continuous glucose monitor (CGM), you’ll encounter the concept of “time in range,” which tracks what percentage of the day your blood sugar stays between 70 and 180 mg/dL. The general goal is at least 70% of readings within that window, which works out to roughly 17 out of 24 hours per day. This metric captures something that fasting readings and A1C miss: how much your blood sugar swings throughout the day. Two people can have the same A1C but very different patterns of spikes and dips, and time in range helps reveal those differences.
Why Morning Readings Run High
Many people with type 2 diabetes notice that their fasting number is stubbornly higher than expected, even when they ate well the night before. There are a few common explanations.
The most frequent is the dawn phenomenon. In the early morning hours, your body releases cortisol and growth hormone to prepare you for waking up. These hormones signal the liver to release stored glucose. In someone without diabetes, the pancreas responds with enough insulin to keep things level. With type 2 diabetes, your body either can’t produce enough insulin or can’t use it efficiently enough to counteract that surge, so you wake up with an elevated reading.
A simpler cause is that your evening medication dose isn’t lasting through the night. If your blood sugar is in range at bedtime but climbs overnight, this is the likely culprit. On the other hand, if your reading is already high at bedtime, the problem is more likely related to a late dinner, a large bedtime snack, or insufficient medication with your evening meal. Checking your blood sugar at bedtime and again first thing in the morning for several nights can help you and your doctor identify which pattern applies.
When Blood Sugar Drops Too Low
Low blood sugar, or hypoglycemia, is defined as a reading below 70 mg/dL. Symptoms include shakiness, sweating, confusion, irritability, and a rapid heartbeat. A reading below 54 mg/dL is considered severe and can lead to seizures, loss of consciousness, or the inability to treat yourself without help.
Hypoglycemia is more common in people who take insulin or certain oral medications that stimulate the pancreas to produce more insulin. Skipping meals, exercising more than usual, or drinking alcohol on an empty stomach can all trigger a low. If you’re on medications that carry this risk, keeping fast-acting glucose (juice, glucose tablets, or regular soda) within reach is a practical safeguard.
Adjusted Targets for Older Adults
Blood sugar targets aren’t the same for everyone, and age is one of the biggest reasons they shift. For older adults, especially those managing several health conditions or taking multiple medications, aggressive blood sugar control can do more harm than good. The risk of a dangerous low, which can cause falls, confusion, or hospitalization, often outweighs the long-term benefits of keeping numbers tightly controlled.
For an otherwise healthy older adult with few risk factors for hypoglycemia, tighter targets may still make sense because the primary purpose of tight control is preventing complications years down the line. But for someone with limited life expectancy, cognitive decline, or frequent lows, a higher A1C target (sometimes 7.5% to 8% or above) can be the safer, more realistic goal. These decisions are always individualized.
Emergency Blood Sugar Levels
Extremely high blood sugar is a medical emergency. A condition called hyperosmolar hyperglycemic state, or HHS, occurs when blood sugar climbs above 600 mg/dL. HHS is more common in type 2 diabetes than in type 1, and it develops over days or weeks, often triggered by illness, infection, or missed medication. Symptoms include extreme thirst, frequent urination, confusion, and eventually loss of consciousness. A blood sugar reading over 600 mg/dL warrants a call to 911.
Readings that stay persistently above 250 to 300 mg/dL, even if they don’t reach the HHS threshold, still signal that something in your management plan isn’t working and needs attention.