All About Blood Sugar

By Melinda Maryniuk, MEd, RD, CDCES

What should my blood sugar be?

Your blood sugar levels will vary throughout the day. Generally speaking, your glucose will be lower before a meal and higher after a meal. Check with your doctor or healthcare provider to find out what specific goals are right for you, but here are the general goals for people with diabetes.

Before breakfast and before meals: 80 – 130 mg/dl

Two hours after meals: Less than 180 mg/dl

Bedtime: 90 – 150 mg/dl

When do I check?

It depends. Checking your blood sugar first thing in the morning can give you valuable information for managing your diabetes. If you take insulin, your doctor may also ask you to check throughout the day, checking before and after some meals, or at bedtime.

If you’re starting a new diabetes medicine, you may need to check more often to see how it is working. Or, if you are trying to figure out how certain foods affect your blood sugar, you may want to check before and 2 hours after eating (also called paired checking).

Other times to check more often are during an illness, if you are worried about a low blood sugar, or when you’re starting a new exercise routine or meal plan.

What are things that affect blood sugar?

While there are many factors that can affect blood sugar, these are some of the most common. Keep records and learn what may affect your blood sugar.

Things that can raise blood sugar:

  • Food, especially carbohydrates (bread, starches, fruit, grains, legumes, milk, yogurt, and sweets)
  • Forgetting to take medicine
  • Illness, surgery, or stressful situations

Things that can lower blood sugar:

  • Physical activity
  • Taking too much medicine
  • Alcohol (sometimes)

Why does it matter?

1. Too much sugar in the blood can cause serious problems. When things in the body are working as they should, hormones (such as insulin) keep blood sugar levels in the right balance. Not too high, and not too low. But for people with diabetes, there is either not enough insulin or it’s not working correctly, and blood sugar can start creeping up to levels that are not healthy.

2. Over time, high blood sugar levels can damage blood vessels which can lead to problems such as heart disease, stroke, vision loss, nerve pain and kidney damage. These problems can be prevented when blood sugar levels stay in target range.

Learn to take action.

Checking your blood sugar and keeping good records allows you and your doctor to monitor the progress of your diabetes treatment. Talk with your doctor or healthcare provider about your numbers so that you know what actions to take and how your diabetes is doing.

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