A blood sugar of 85 mg/dL is not low. It falls squarely within the normal range for both fasting and non-fasting readings. The clinical threshold for low blood sugar (hypoglycemia) is 70 mg/dL, which means 85 mg/dL sits comfortably 15 points above that cutoff.
Where 85 mg/dL Falls in the Normal Range
A normal fasting blood sugar is anything below 100 mg/dL. After eating, blood sugar naturally rises and then settles back down; a reading below 140 mg/dL two hours after a meal is also considered normal. At 85 mg/dL, your reading is well within healthy territory whether you measured it before breakfast or a couple of hours after lunch.
For context, here’s how the standard ranges break down for fasting readings:
- Normal: below 100 mg/dL
- Prediabetes: 100 to 125 mg/dL
- Diabetes: 126 mg/dL or higher (on two separate tests)
An 85 mg/dL fasting reading is actually right in the middle of the healthy zone. Many clinicians consider the 70 to 99 mg/dL window the sweet spot for fasting glucose.
Why You Might Feel “Low” at 85
If your blood sugar reads 85 but you feel shaky, lightheaded, or irritable, you’re not imagining it. What matters isn’t just the number on the meter but how quickly your blood sugar dropped to get there. If you ate a large, carb-heavy meal and your glucose spiked to 180 or 200 mg/dL, then fell rapidly back to 85, your body can interpret that steep decline as a threat. You may experience classic low blood sugar symptoms even though your actual level is perfectly normal.
This is sometimes called relative hypoglycemia or pseudo-hypoglycemia. It’s especially common in people who run higher blood sugars on a regular basis, such as those with poorly controlled diabetes or insulin resistance. Their bodies have adapted to elevated glucose, so a normal reading can feel uncomfortably low by comparison. Over time, as blood sugar control improves, these false-alarm symptoms typically fade.
When Blood Sugar Actually Becomes Low
True hypoglycemia starts at 70 mg/dL. Below that point, the body begins sending distress signals: shakiness, sweating, a racing heartbeat, sudden hunger, and difficulty concentrating. These symptoms serve as an early warning to eat something and bring glucose back up.
Severe hypoglycemia, defined as blood sugar below 54 mg/dL, is a more urgent situation. At that level, the brain isn’t getting enough fuel and symptoms can escalate to confusion, blurred vision, slurred speech, and even loss of consciousness. This level of low blood sugar is rare in people without diabetes but can happen in those taking insulin or certain diabetes medications.
The 15-15 Rule for Actual Lows
If your blood sugar does drop below 70 mg/dL, the standard approach is straightforward: eat or drink 15 to 20 grams of fast-acting carbohydrates. That’s about half a cup of juice, a tablespoon of honey, or 3 to 4 glucose tablets. Wait 15 minutes, then recheck your level. If it’s still below 70, repeat with another 15 grams of carbs. Continue this cycle until your reading is back in the normal range.
At 85 mg/dL, you don’t need this intervention. If you’re feeling off, a small balanced snack with some protein and carbs can help stabilize things, but there’s no medical urgency at this level.
Blood Sugar of 85 During Pregnancy
Pregnant women are often monitored more closely for blood sugar fluctuations, especially if gestational diabetes is a concern. Even by pregnancy standards, 85 mg/dL is a healthy number. The recommended fasting target during pregnancy is 95 mg/dL or less, so 85 falls well within range. That said, persistently low blood sugar during pregnancy (consistently in the low 60s or below) can be a concern worth raising with your provider, since steady glucose delivery matters for fetal development.
What Can Cause Blood Sugar to Sit on the Lower End
Some people naturally run blood sugars in the 70s and 80s and feel perfectly fine. But if you’re consistently seeing readings in the low 80s or upper 70s and experiencing symptoms, a few common factors could be at play:
- Skipping meals or eating infrequently: Going long stretches without food can gradually draw down your glucose stores, especially if you’re active.
- Intense or prolonged exercise: Physical activity burns through glucose. A post-workout reading in the low 80s is common and not a problem, though you may feel depleted.
- Alcohol consumption: Alcohol can suppress your liver’s ability to release stored glucose, leading to lower readings several hours after drinking.
- Diabetes medications: Insulin and certain oral medications are the most common cause of blood sugar dipping lower than intended. If you’re on these medications and frequently seeing readings in the 70s or low 80s with symptoms, your dosing may need adjustment.
For most people, a blood sugar of 85 mg/dL is a sign that your metabolism is doing exactly what it should. It’s a normal, healthy number that requires no treatment and no concern.