A fasting blood sugar of 98 mg/dL falls within the normal range of 70 to 99 mg/dL, so yes, it’s technically a good reading. But it sits just one point below the prediabetes threshold of 100 mg/dL, which makes it worth paying attention to rather than dismissing entirely.
Where 98 Falls on the Scale
The American Diabetes Association defines three fasting blood sugar categories: normal (below 100 mg/dL), prediabetes (100 to 125 mg/dL), and diabetes (126 mg/dL or higher). By that standard, 98 clears the cutoff for normal. The World Health Organization uses a more lenient threshold, not classifying impaired fasting glucose until 110 mg/dL, which puts 98 even more comfortably in healthy territory.
Context matters, though. If you checked your blood sugar after eating, 98 is an excellent number. Post-meal glucose in healthy people can rise well above 100, and anything under 140 two hours after a meal is considered normal. A reading of 98 after food suggests your body is processing glucose efficiently.
Normal vs. Optimal
There’s a meaningful difference between “clinically normal” and “optimal.” Research on long-term health outcomes suggests the sweet spot for fasting glucose is between 80 and 94 mg/dL. Above or below that range, the risk of death from all causes begins to creep up. A reading of 98 is still safe, but it’s on the higher end of what the data considers ideal.
Think of it like blood pressure. A reading that’s technically normal but consistently near the upper boundary tells a different story than one sitting comfortably in the middle. If your fasting glucose regularly lands in the high 90s, your body may be working harder to keep blood sugar in check, and that effort could eventually fall short. People whose fasting glucose drifts from the low 90s to the high 90s over several years are often on a trajectory toward prediabetes, even though no single reading looks alarming.
Why Timing and Circumstances Matter
A single blood sugar reading is a snapshot, not a diagnosis. Your number can shift significantly based on when and what you last ate, how well you slept, your stress level, whether you exercised recently, and even the time of morning you tested. Fasting glucose tends to be slightly higher if you slept poorly or are fighting off an illness.
If you got this number from a home glucose meter, keep in mind that most consumer meters have a margin of error of about 15%. A reading of 98 could actually be anywhere from the mid-80s to the low 110s. Lab-drawn blood tests are more precise, which is why doctors use them for official diagnoses.
Special Cases: Pregnancy
If you’re pregnant, the standards are stricter. The American College of Obstetricians and Gynecologists recommends fasting glucose below 90 mg/dL during pregnancy, and the American Diabetes Association sets the target at or below 95 mg/dL for gestational diabetes management. Under those guidelines, 98 would be slightly elevated. Pregnant women with readings in this range are typically monitored more closely because even modest glucose elevations during pregnancy can affect fetal development.
What You Can Do With a Reading of 98
You don’t need to treat a fasting glucose of 98, but you can use it as a signal to make small adjustments that keep the number from climbing. The same habits that prevent prediabetes also tend to push borderline-normal readings into the more optimal range.
- Move after meals. Even a 10 to 15 minute walk after eating helps your muscles absorb glucose from the bloodstream, reducing the spike your pancreas has to manage.
- Prioritize sleep. Consistently getting fewer than six hours raises fasting glucose by impairing the way your cells respond to insulin.
- Shift your carbohydrate choices. Replacing refined carbs (white bread, sugary drinks, pastries) with whole grains, legumes, and vegetables slows the rate at which glucose enters your blood.
- Watch the trend, not just the number. If you have access to previous lab results, compare your fasting glucose over time. A reading that was 88 three years ago and is now 98 tells you more than any single number can.
A fasting glucose of 98 is not a problem today. But it’s close enough to the prediabetes line that tracking it over time, rather than filing it away and forgetting it, is the smartest thing you can do with this information.