Carbohydrates, or "carbs", along with proteins and fats, are one of the 3 main nutrients that provide energy. Understanding the types of carbs and when to eat them can help better manage post meal blood glucose.
Found in things such as desserts, soda, and candy. They are also found naturally in
milk and fruit.
Starches are found in things such as bread and pasta. They are found naturally in beans,
potatoes and corn.
When eaten, sugars and starches are broken down into a simple sugar called glucose. Glucose
enters the blood stream to be taken through the body. Insulin then allows glucose to leave the
bloodstream and enter the body’s cells and be used for energy. Some carbohydrates raise the
blood sugar quickly and others more slowly. Regardless, carbohydrates have the largest impact
on blood sugar than any other nutrient.
Dietary fiber is a part of plant-based food that cannot be digested. It is found in whole grains,
vegetables, fruit, and beans. It can help control blood sugar by slowing your body’s absorption
of sugar but does not directly raise blood sugar like sugar and starches.
Consistent carbohydrate meals and snack
Choosing the appropriate quantity and quality of carbs from day to day at each meal and snack
can help keep blood sugars more consistent and make it easier to manage diabetes. Use your
CGM data to guide the amount and type of carbohydrates that work best for you. Your DCES
can be a valuable resource to guide your needs based on your food preferences and usual
Food and medication timing
- Rapid-acting insulins, sometimes called “mealtime” or “bolus” insulins, start working in 10-15 minutes and work the hardest to lower blood sugar levels in 1-2 hours. It is important to eat within 15-30 minutes of taking rapid-acting insulin, or blood sugar levels could drop too low.
- NPH is an intermediate-acting insulin. It’s peak action takes place approximately 4 to 8 hours after injection. When taking NPH insulin during the day, it is important to eat within the peak action time.
- Meglitinides (Repaglinide and Nateglinide) are oral medications that stimulate the pancreas to produce more insulin fairly quickly. When taking meglitinides, it is important to eat within about 15-30 minutes.
Space Out Eating Times
Spacing out times to eat can help keep blood glucose levels more even throughout the day. It's important to create gaps between eating times to allow the body to rest from the hard work it takes to digest and absorb food. During the resting phase the pancreas feels less pressured to constantly keep up with having to make more insulin to move glucose out of the bloodstream and into the muscles and cells. Insulin keeps working for 3-4 hours after eating to help blood glucose levels return to pre meal levels. For this reason, grazing on food can prove to be detrimental in managing not only diabetes but also weight. For people with diabetes who need mealtime insulin, when meals are eaten too close together, both food and insulin can stack on top of each other, resulting in both chronic elevated blood sugar as well as an increased risk of hypoglycemia.
A general rule of thumb is to allow at least 2 hours between eating times (the most typical time it takes for blood glucose to peak after eating). For meals, allow 3-4 hours of a gap.
Timing of Physical Activity
Physical activity plays an important role in diabetes management. Whether it is a brisk walk, a
bike ride or performing chores around the house, any muscle movement helps the
insulin work more efficiently. It is recommended to get least 150 minutes of vigorous physical activity
each week. Engaging in easy physical activity after meals, when glucose is on the rise, can
improve post-meal blood sugar control. When we have muscle movement, it helps our body be
more sensitive to the insulin we are producing. The insulin is able to work more efficiently and
as a result can effectively lower blood glucose levels. Know your blood glucose trends by checking your CGM
data. Be sure to address possible risks for low blood sugar prior to beginning activity post
meals, especially if taking mealtime insulin or oral medications such as sulfonylureas and
Late-night snacking can lead to excessive calorie intake. Nighttime snacking can become
habitual, especially if you are a “night-owl.” This is a time when we tend to be LESS active and it
is more difficult to lower post-snack blood sugars. Most people who snack at night tend to
graze and mindlessly eat more than they realize. Have an action plan ready when you get the
late-night munchies. Have some low-calorie, low-carb snacks available (such as cut-up veggies)
to munch on. Portion out your snack and put the rest away.
Research suggests that limiting food intake in the evening can improve blood glucose in those
with type 2 diabetes. It may be beneficial to limit snacking after dinner or during evening
hours. Have healthy foods available and eat in moderation if you are hungry before bedtime.
©Gary Scheiner MS, CDCES – Integrated Diabetes Services. May be reproduced and used for patient education, but not sold.