BP & SugarHigh Blood Sugar In The Morning: Dawn Phenomenon Explained
Many people see their highest reading of the day before breakfast. Often the cause is the dawn phenomenon: hormones released early in the morning raise glucose.
Common Causes
- Dawn phenomenon (cortisol and growth hormone)
- A late or large evening snack
- Medication wearing off overnight
- Poor sleep or illness
How To Find Your Cause
Log your bedtime reading and your fasting reading for one or two weeks and share them with your doctor. The pattern helps decide what to change.
Fasting ranges are in Fasting Blood Sugar Levels: Normal, Prediabetes And Diabetes.
Helpful Habits
- Finish dinner earlier.
- Take a short walk after dinner.
- Keep a consistent sleep schedule.
Track blood sugar and blood pressure in one app
Free on iPhone. Private, works offline, doctor-ready reports.
Frequently Asked Questions
Is high morning blood sugar dangerous?
Repeated high fasting readings deserve a talk with your doctor; they can often be managed with small changes.
Track blood sugar and blood pressure in one app
Free on iPhone. Private, works offline, doctor-ready reports.
This content is for information only and does not replace advice from your doctor. If you think you have very low or very high blood sugar, or a blood pressure above 180/120 mmHg with symptoms, seek medical help immediately.
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