Controlling Blood Sugar Spikes With Diet, Exercise

If you have diabetes, you know your overall blood sugar levels (you may hear it called glucose) show how well you’ve got your condition under control. When your level stays normal and steady, you lower your chance of problems like vision loss and kidney disease. You also have more energy.

Medicine can help balance your blood sugar. But the foods you eat and how active you are make a difference, too.


Get into a routine. Eat too much at one sitting and your blood sugar could skyrocket. On the other hand, if you don’t eat enough food, or take in fewer carbs than usual, your glucose level may drop, especially if you take certain diabetes medicines. Some people find it easier to manage their blood sugar if they eat at the same time each day. Talk to your doctor about a meal plan that’s right for you. Once you have it in place, stick with it.

Index your food. When you eat carbs, your blood sugar spikes. A food’s glycemic index (GI) measures how fast this can happen. The higher the number, the more quickly your glucose levels will rise. Processed foods like pretzels, white rice, and white bread tend to have a high GI. Opt for low-GI foods like:

  • Dried beans and legumes
  • Oatmeal
  • Fruit
  • Non-starchy vegetables


If you do eat something high on the index, balance it with low-GI side dishes. This can help keep your blood sugar on track.

Count carbs. If you take insulin, you may find this easier to do.  You’ll add up the number of total carbs at each meal and adjust your insulin dose as needed. For a few days, track the food you eat and what your blood sugar level is 2 hours after you finish. It'll help you see how different meals affect you.

Boost your fiber. It isn’t broken down by your body, so it doesn’t affect your blood sugar. (Although many foods with fiber contain sugars and starches that do.) Eating 25-30 grams of fiber (like you find in oatmeal) each day may help you better manage your blood sugar. Increase to this amount slowly, though. And drink lots of water so you don’t get constipated.

Keep a water bottle handy. Not having enough fluid in your body can wreak havoc on your blood sugar levels. Choose water to quench your thirst instead of juice or soda. Don’t like the taste? Choose unsweetened teas.


Make it part of your routine. Being active makes your body more sensitive to insulin. That helps your blood sugar stay steady. Once your doctor gives you the OK, try an aerobic workout that gets your heart pumping, like walking or biking. Your goal should be 30 minutes, 5 days a week. But even 5 minutes is a good start. When you’re ready, add resistance training. This strengthens your muscles, where most blood glucose is stored.

Choose the “right” time to break a sweat. Some people find that an early morning workout keeps their blood sugar low all day. Still, that might not be true for you. You may need to try working out a few different times during the day before you find a schedule that helps level off your blood sugar. Even once you do, be safe. Always carry glucose tablets or an emergency snack with you, especially if you take insulin. Check in with your doctor with any questions.


Fight the post-meal crash. An easy workout, like a 10-15 minute walk after a meal, can keep your blood sugar from spiking. More blood gets sent to your muscles instead of your stomach. That means you take in sugars better. Instead of turning on the TV after you eat, clear the kitchen table and wash the dishes or take a walk around the block.

Listen to your body. Exercise can affect your blood sugar for 24 to 48 hours. That makes it a good idea to check your glucose after each workout. It'll help you tune into how your body reacts when you’re active. You may start to notice other patterns that can help you control your blood sugar better.

WebMD Medical Reference Reviewed by Michael Dansinger, MD on June 12, 2020



National Institute of Diabetes and Digestive and Kidney Diseases: “Know Your Blood Sugar Numbers: Use Them to Manage Your Diabetes,” “4 Steps to Manage Your Diabetes for Life,” “Diabetes Diet, Eating & Physical Activity.”

American Diabetes Association: “Glycemic Index and Diabetes,” “Carbohydrate Counting,” “Factors Affecting Blood Glucose,” “What Can I Drink?” “Blood Glucose and Exercise.”

Harvard Medical School: “A good guide to good carbs: The glycemic index.”

University of Michigan C.S. Mott Children’s Hospital: “Learning to Control After-Meal High Blood Sugars.”

Mayo Clinic: “Diabetes management: How lifestyle, daily routine affect blood sugar.”

Joslin Diabetes Center: “How Does Fiber Affect Blood Glucose Levels?” “Why Do Blood Glucose Levels Sometimes Go Up After Physical Activity?”

Diabetes Canada: “Physical Activity and Diabetes,” “7 Things You Need to Know About Exercising with Diabetes.”

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