For most adults without diabetes, blood sugar stays between about 70 and 140 mg/dL throughout the day, rising temporarily after meals and dipping to its lowest point after several hours without food. If you have diabetes, the recommended targets are slightly wider: 80 to 130 mg/dL before meals and under 180 mg/dL one to two hours after eating, according to the American Diabetes Association’s 2025 Standards of Care.
Normal Ranges Before and After Meals
Your blood sugar isn’t a fixed number. It moves constantly in response to what you eat, how active you are, your stress level, and your hormones. In a person without diabetes, fasting blood sugar (first thing in the morning or after not eating for eight or more hours) typically falls between 70 and 99 mg/dL. After a meal, it may climb to 120 or 140 mg/dL, then return to baseline within two to three hours as insulin clears the glucose from your bloodstream.
A fasting reading of 100 to 125 mg/dL falls in the prediabetes range. At 126 mg/dL or higher on two separate tests, the threshold for a diabetes diagnosis is met.
Targets if You Have Diabetes
People with diabetes can’t clear glucose as efficiently, so their targets reflect that reality. The ADA recommends these goals for most nonpregnant adults with diabetes:
- Before meals: 80 to 130 mg/dL
- One to two hours after starting a meal: under 180 mg/dL
- A1C (a three-month average): under 7%
An A1C of 7% translates to an estimated average glucose of about 154 mg/dL over the course of a day. At 6%, the average is closer to 126 mg/dL, and at 8% it’s roughly 183 mg/dL. These averages include all the peaks after meals and all the dips overnight, so your actual readings at any given moment will be higher or lower than the number your A1C suggests.
These targets aren’t one-size-fits-all. Some people benefit from tighter control (an A1C below 7%), especially if they can achieve it without frequent low blood sugar episodes. Others, particularly older adults or those with other serious health conditions, may do better with a more relaxed goal, such as an A1C under 8%.
When Blood Sugar Drops Too Low
Blood sugar below 70 mg/dL is considered hypoglycemia. Early symptoms include sweating, a racing heartbeat, anxiety, and sudden hunger. If it continues to fall, you may develop a headache, dizziness, confusion, or difficulty speaking. Severe lows can lead to seizures or loss of consciousness.
Hypoglycemia is most common in people taking insulin or certain oral diabetes medications, but it can also happen after intense exercise or a long stretch without eating. The ADA recommends spending less than 4% of the day below 70 mg/dL and less than 1% below 54 mg/dL if you’re using a continuous glucose monitor to track your numbers.
Why Morning Readings Run Higher
Many people notice their blood sugar is surprisingly elevated first thing in the morning, even if they haven’t eaten since dinner. This is called the dawn phenomenon, and it typically happens between 4 a.m. and 8 a.m. Your body naturally releases a surge of hormones during this window, including cortisol, growth hormone, and glucagon. These hormones work against insulin, prompting your liver to release stored glucose to fuel your body for the day ahead. In someone without diabetes, the pancreas compensates by producing extra insulin. In someone with diabetes, that compensation is incomplete, and fasting readings may be higher than expected.
How Exercise Shifts Your Numbers
Physical activity lowers blood sugar, sometimes dramatically. Your muscles pull glucose from your bloodstream for fuel during a workout, and the effect doesn’t stop when you do. After exercise, your body replenishes the sugar stored in your muscles and liver by continuing to draw from your blood. The more intense the workout, the longer this process takes. Low blood sugar can occur four to eight hours after exercise, which is why some people experience unexpected dips in the evening after an afternoon run or gym session.
If you take insulin or track your glucose closely, checking your levels before, during (every 30 minutes for long workouts), and after exercise helps you spot trends. A small snack with slow-digesting carbohydrates after a tough session can prevent a delayed drop.
What These Numbers Mean Day to Day
Your blood sugar will never sit at one constant number, and it’s not supposed to. A healthy pattern looks like gentle waves: a rise after meals, a gradual return to baseline, and a relatively stable overnight period. What matters more than any single reading is the overall pattern. Consistently landing above 140 mg/dL before meals or above 180 mg/dL after meals suggests your glucose management needs attention. Consistently dipping below 70 mg/dL means your medication, meals, or activity level may need adjusting.
If you’re using a continuous glucose monitor, the concept of “time in range” captures this idea in a single metric. Spending more than 70% of the day between 70 and 180 mg/dL is the goal for most adults with diabetes. That still allows room for occasional spikes and dips, because perfection isn’t the target. Consistency is.