If you check your blood sugar at home, the reading will be lower than 70 mg/dL on your glucose monitor. At the hospital, you will likely have blood samples taken from your vein to: 1  Measure your blood sugar level.  Diagnose the cause of your low blood sugar.
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Frequent or ongoing high blood sugar can cause damage to your nerves, blood vessels, and organs. It can also lead to other serious conditions. People with type 1 diabetes are prone to a build-up of acids in the blood called ketoacidosis.
http://www.webmd.com/diabetes/guide/diabetes-hyperglycemia
Postprandial or after-meal hyperglycemia. This is blood sugar that's higher than 180 mg/dL 2 hours after you eat. People without diabetes rarely have blood sugar levels over 140 mg/dL after a meal, unless it’s really large.
http://www.webmd.com/diabetes/guide/diabetes-hyperglycemia
The blood carries glucose (blood sugar) to all the cells in the body. To carry glucose into the cells as an energy supply, cells need help from insulin. Insulin is a hormone made by the pancreas, an organ near the stomach. The pancreas releases insulin into the blood, based upon the blood sugar level.
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Diabetes mellitus is one of several persistent conditions causing high blood sugar levels. For someone with diabetes, hyperglycemia has many possible causes: Carbohydrates: Eating food containing too many carbohydrates, a form of sugar. The body of a person with diabetes cannot process high levels of carbohydrates fast enough to convert it into energy. Blood sugar levels in patients with diabetes can rise within hours after eating.
http://www.emedicinehealth.com/high_blood_sugar_hyperglycemia/article_em.htm
Blood sugar control is at the center of any diabetes treatment plan. High blood sugar, or hyperglycemia, is a major concern, and can affect people with both type 1 and type 2 diabetes . There are two main kinds: Fasting hyperglycemia . This is blood sugar that's higher than 130 mg/dL (milligrams per deciliter) after not eating or drinking for at least 8 hours.
http://www.webmd.com/diabetes/guide/diabetes-hyperglycemia
Blood sugar control is at the center of any diabetes treatment plan. High blood sugar, or hyperglycemia, is a major concern, and can affect people with both type 1 and type 2 diabetes . Fasting hyperglycemia .
http://www.webmd.com/diabetes/guide/diabetes-hyperglycemia
Whenever the glucose (sugar) level in one's blood rises high temporarily, this condition is known as hyperglycemia. The opposite condition, low blood sugar, is called hypoglycemia. Glucose comes from most foods, and the body uses other chemicals to create glucose in the liver and muscles.
http://www.emedicinehealth.com/high_blood_sugar_hyperglycemia/article_em.htm
Causes of High blood sugar: The following medical conditions are some of the possible causes of High blood sugar. There are likely to be other possible causes, so ask your doctor about your symptoms. Conditions listing medical symptoms: High blood sugar: The following list of conditions have 'High blood sugar' or similar listed as a symptom in our database. This computer-generated list may be inaccurate or incomplete. Always seek prompt professional medical advice about the cause of any symptom. Select from the following alphabetical view of conditions which include a symptom of High blood sugar or choose View All. View All A C D G H I L N O P S T. Adrenal Cortex Diseases ...
http://www.rightdiagnosis.com/symptoms/high_blood_sugar/causes.htm
1 When food, exercise, and insulin are not balanced, blood sugar levels rise. 2  Stress: Emotions can play a role in causing hyperglycemia, but should not be used as an excuse for poor control of diabetes.  Low levels of exercise: Daily exercise is a critical contributor to regulating blood sugar levels.
http://www.emedicinehealth.com/high_blood_sugar_hyperglycemia/article_em.htm
what causes blood sugar
Carbohydrates causes blood sugar. Carbohydrates cause blood sugar.