Blood Sugar and Food
Food raises your blood sugar the most. Stress, certain medicines, and some kinds of exercise can also raise your blood sugar.
The three major nutrients in food are carbohydrates, protein, and fat.
- Your body quickly turns carbohydrates into a sugar called glucose. This raises your blood sugar level. Carbohydrates are found in cereal, bread, pasta, potato, and rice. Fruit and some vegetables like carrots also have carbohydrates.
- Protein and fat can change your blood sugar too, but not as fast.
If you have diabetes, you may need to eat carbohydrate snacks during the day. This will help balance your blood sugar. This is particularly important if you have type 1 diabetes. Some people with type 2 diabetes who take insulin or other medicines that can cause hypoglycemia (low blood sugar) may also benefit from eating snacks during the day.
Learning how to count the carbohydrates that you eat (carb counting) helps you plan what to eat. It will also keep your blood sugar under control.
Your health care provider may tell you to eat a snack at certain times of the day, most often at bedtime. This helps keep your blood sugar from getting too low at night. Other times, you may have a snack before or during exercise for the same reason. Ask your provider about the snacks you can and you can't have.
Needing to snack to prevent low blood sugar has become much less common because of new types of insulin that are better at matching the insulin your body needs at specific times.
If you have type 2 diabetes and are taking insulin and often need to snack during the day and are gaining weight, your doses of insulin may be too high and you should talk to your provider about this.
You will also need to ask about what snacks to avoid.
Snacks for a Purpose
Your provider can tell you if you should snack at certain times to keep from having low blood sugar.
This will be based on your:
- Diabetes treatment plan from your provider
- Expected physical activity
- Low blood sugar pattern
Most often, your snacks will be easy to digest foods that have 15 to 45 grams of carbohydrates.
Snack foods that have 15 grams (g) of carbohydrates are:
- Half cup (107 g) of canned fruit (without the juice or syrup)
- Half banana
- One medium apple
- One cup (173 g) melon balls
- Two small cookies
- Ten potato chips (varies with size of chips)
- Six jelly beans (varies with size of pieces)
Snacks for Enjoyment
Having diabetes does not mean that you must stop eating snacks. It does mean that you should know what a snack does to your blood sugar. You also need to know what healthy snacks are so you can choose a snack that will not raise your blood sugar or make you gain weight. Ask your provider about what snacks you can eat. Also ask if you need to change your treatment (such as taking extra insulin shots) for snacks.
Snacks with no carbohydrates change your blood sugar the least. The healthiest snacks usually do not have many calories.
Read food labels for carbohydrates and calories. You can also use carbohydrate counting apps or books. Over time, it will get easier for you to tell how many carbohydrates are in foods or snacks.
Some low carbohydrate snacks, such as nuts and seeds, are high in calories. Some low carbohydrate snacks are:
- Celery sticks
- Peanuts (not honey-coated or glazed)
- Sunflower seeds
Healthy snacking - diabetes; Low blood sugar - snacking; Hypoglycemia - snacking
American Diabetes Association website. Get Smart on Carb Counting. www.diabetes.org/nutrition/understanding-carbs/carb-counting. Accessed April 23, 2020.
American Diabetes Association. 5. Facilitating Behavior Change and Well-being to Improve Health Outcomes: Standards of Medical Care in Diabetes-2020. Diabetes Care. 2020;43(Suppl 1):S48–S65. PMID: 31862748 pubmed.ncbi.nlm.nih.gov/31862748/.
National Institute of Diabetes and Digestive and Kidney Diseases website. Diabetes Diet, Eating, & Physical Activity. www.niddk.nih.gov/health-information/diabetes/overview/diet-eating-physical-activity/carbohydrate-counting. December 2016. Accessed April 23, 2020.
Review Date 1/26/2020
Updated by: Brent Wisse, MD, board certified in Metabolism/Endocrinology, Seattle, WA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.