How to Lower Blood Sugar: What Actually Works and When to Get Help

What 'high blood sugar' means and when to act

Blood sugar (glucose) fluctuates throughout the day based on meals, activity, stress, sleep, illness, and medications. A reading above the target range is called hyperglycemia. For most people with diabetes, clinicians set individualized targets — commonly a fasting level under 130 mg/dL and under 180 mg/dL one to two hours after eating, though targets vary by person and condition 1Ref 1American Diabetes Association Professional Practice Committee (2024).Standards of Care in Diabetes—2024.Individualized blood sugar targets; medication management including correction dosing; HbA1c as measure of long-term control; safe exercise guidance; guidance against self-adjusting medications.

A single elevated reading without symptoms means something different from persistently high readings or a very high reading with symptoms. Context matters greatly before deciding what to do.

Steps that can help bring blood sugar down (for people with diabetes)

Take your medication as prescribed. If a clinician has given you a correction dose of insulin for high readings, use it as directed. Do not improvise a dose or increase amounts beyond what was prescribed 1Ref 1American Diabetes Association Professional Practice Committee (2024).Standards of Care in Diabetes—2024.Individualized blood sugar targets; medication management including correction dosing; HbA1c as measure of long-term control; safe exercise guidance; guidance against self-adjusting medications.

Gentle physical activity — such as a brisk walk — can lower blood sugar meaningfully in people with type 2 diabetes who are not in ketosis. Avoid vigorous exercise if your reading is very high, as it can paradoxically raise blood sugar in people with type 1 diabetes who lack sufficient insulin 1Ref 1American Diabetes Association Professional Practice Committee (2024).Standards of Care in Diabetes—2024.Individualized blood sugar targets; medication management including correction dosing; HbA1c as measure of long-term control; safe exercise guidance; guidance against self-adjusting medications.

Drink water. Dehydration concentrates glucose in the blood; drinking plain water helps the kidneys excrete excess glucose.

Avoid sugary foods and drinks while your level is elevated.

Recheck in one to two hours to see whether the reading is trending down.

What does not work — and what to avoid

No food, supplement, or drink has a reliably fast enough effect to substitute for medication in someone who needs it. Cinnamon, apple cider vinegar, and similar remedies are sometimes promoted online — at best they may have very modest effects over time and should not be relied on in any acute situation.

Skipping meals to bring a number down can be counterproductive and dangerous if you take insulin or certain other diabetes medications, as it raises the risk of a low blood sugar rebound. Do not adjust medication doses beyond what your clinician prescribed without speaking to them first 1Ref 1American Diabetes Association Professional Practice Committee (2024).Standards of Care in Diabetes—2024.Individualized blood sugar targets; medication management including correction dosing; HbA1c as measure of long-term control; safe exercise guidance; guidance against self-adjusting medications.

For people with type 1 diabetes specifically: a very high reading without insulin can progress to diabetic ketoacidosis (DKA) — a life-threatening emergency — much faster than in type 2 diabetes 2Ref 2American Diabetes Association Professional Practice Committee (2024).6. Glycemic Goals and Hypoglycemia: Standards of Care in Diabetes—2024.DKA risk in type 1 diabetes with very high blood sugar; glycemic goals and emergency thresholds.

If you are not diagnosed with diabetes

A single high fasting blood sugar — especially if you are sick, stressed, or just ate a large meal — does not automatically mean diabetes. Illness, steroid medications, and poor sleep can temporarily push blood sugar up 3Ref 3US Preventive Services Task Force (2021).Screening for Prediabetes and Type 2 Diabetes: US Preventive Services Task Force Recommendation Statement.Screening recommendation for adults 35–70 with overweight/obesity; context for interpreting an isolated high blood sugar reading in undiagnosed individuals.

However, if you are consistently seeing elevated readings, or if you have symptoms of high blood sugar (unusual thirst, frequent urination, blurry vision, fatigue, slow-healing cuts), that is a strong reason to see a clinician for formal evaluation. The USPSTF recommends screening for prediabetes and type 2 diabetes in adults aged 35 to 70 who have overweight or obesity 3Ref 3US Preventive Services Task Force (2021).Screening for Prediabetes and Type 2 Diabetes: US Preventive Services Task Force Recommendation Statement.Screening recommendation for adults 35–70 with overweight/obesity; context for interpreting an isolated high blood sugar reading in undiagnosed individuals. Do not try to self-treat what may be a new diagnosis.

When your blood sugar plan needs a tune-up

If you regularly see readings outside your target range despite following your plan, that is a signal to contact your clinician — not to increase medication on your own. Blood sugar control often needs adjustment as weight, activity level, other medications, or overall health change 1Ref 1American Diabetes Association Professional Practice Committee (2024).Standards of Care in Diabetes—2024.Individualized blood sugar targets; medication management including correction dosing; HbA1c as measure of long-term control; safe exercise guidance; guidance against self-adjusting medications.

The hemoglobin A1c (HbA1c) test reflects average blood sugar control over roughly the past three months and is the key measure for assessing how well diabetes is managed overall. A telehealth visit can be a convenient way to review recent numbers and adjust the plan.