- With Mayo Clinic endocrinologist
Maria Collazo-Clavell, M.D.
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Maria Collazo-Clavell, M.D.
Maria Collazo-Clavell, M.D.
Dr. Maria Collazo-Clavell is board certified in internal medicine, endocrinology, diabetes and metabolism. She is a consultant in the Division of Endocrinology, Diabetes, Metabolism & Nutrition at Mayo Clinic and an assistant professor at Mayo Clinic College of Medicine.
The Aibonito, Puerto Rico, native has been with Mayo Clinic since 1994.
She is a member of the American Association of Clinical Endocrinologists, the American College of Endocrinology, the American Diabetes Association and The Endocrine Society.
Dr. Collazo-Clavell is medical editor for the Web site's diabetes content and the book "Mayo Clinic on Managing Diabetes." Her clinical interests include management of type 1 and type 2 diabetes, obesity and nutritional disorders.
Risk factors (1)
- Diabetes: Does alcohol and tobacco use increase my risk?
Symptoms (1)
- The 'dawn phenomenon': What causes it?
Causes (1)
- Diabetes and depression: What's the link?
Complications (2)
- Diabetes: How does it affect my liver?
- Blood sugar and mood: Any connection?
Treatments and drugs (2)
- Diabetes management: Does aspirin therapy prevent heart problems?
- Byetta: Can diabetes drug also help me lose weight?
Lifestyle and home remedies (11)
- Vegetarian diet: Can it help me control my diabetes?
- Diabetes: Are electric blankets off-limits?
- Caffeine: Does it affect blood sugar?
- see all in Lifestyle and home remedies
Alternative medicine (1)
- Diabetes treatment: Can cinnamon lower blood sugar?
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Question
The 'dawn phenomenon': What causes it?
What is the "dawn phenomenon" that some people with diabetes experience? Can anything be done about it?
Answer
from Maria Collazo-Clavell, M.D.
The "dawn effect," also called the "dawn phenomenon," is the term used to describe an abnormal early-morning increase in blood sugar (glucose) — usually between 4 a.m. and 8 a.m. — in people with diabetes. The dawn phenomenon is more common in people with type 1 diabetes than in those with type 2 diabetes.
The exact cause of the dawn phenomenon isn't known. Some researchers believe it's due to the natural overnight release of hormones — including growth hormones, cortisol, glucagon and epinephrine — that increase insulin resistance.
High morning blood sugar may also have other causes. Insufficient insulin the night before, incorrect medication dosages or eating carbohydrate snacks at bedtime may cause blood sugar to be elevated in the morning. Checking your blood sugars throughout the night will help you and your doctor to determine if you have the dawn phenomenon or if there's another reason for an elevated morning blood sugar reading.
Based on the results of blood testing throughout the night, your doctor may recommend one of the following options to prevent or correct high blood sugar levels in the morning:
- Not eating a carbohydrate snack at bedtime
- Adjusting your dosage of medication or insulin
- Switching to a different medication
- Using an insulin pump to administer extra insulin during early morning hours
