Carbohydrates and Insulin
Carbohydrates, proteins, and fats are the main nutrients in food that give the body energy. Sugars and starchy foods are examples of carbohydrates. Carbohydrates can raise blood sugar levels more than other nutrients because they are turned into sugars by the digestive system and then absorbed into the bloodstream. That’s why it’s important to know about the different kinds of carbohydrates and how they may affect your child’s blood sugar levels. The more you know, the better you can help your child stay in control of his or her type 1 diabetes.
A basic guide to carbohydrate counting
Carbohydrate counting can help you and your child to better understand how food affects diabetes and help to keep blood sugar levels in check. It also gives you greater flexibility at mealtimes. Your child’s dietitian will work with you to develop a meal plan that fits your child’s needs.
Balancing carbohydrates with insulin
Getting the balance right between carbohydrate (carbs) and insulin is key for maintaining good blood sugar control in children with type 1 diabetes. There are 2 common ways that you can do this:
- Matching carbohydrate intake to the insulin dose (fixed dose). One way to count carbohydrates is to limit the number of servings of carbohydrates your child consumes. Doing so helps one achieve or maintain blood sugar levels on a particular insulin dose. Every child has different needs. Your child’s dietitian will advise on how many carbohydrate servings your child should eat each day. This method requires a certain amount of consistency in terms of meal and snack times as well as carbohydrate counts
- Changing the insulin dose to match carbohydrate intake. Matching the amount of fast-acting, or mealtime, insulin your child takes before eating to the amount of carbohydrates in the meal is another way to balance carbohydrates and insulin. This can allow for more flexibility and choice at mealtime, but may take more time and effort to figure out
Your child’s dietitian or other health care professional can help you work out how much insulin is needed for the amount of carbohydrate eaten. This is called the insulin-to-carbohydrate ratio.
It is important to know that:
- This ratio varies with age and weight, so this will change as your child grows
- This ratio also varies throughout the day
You may find that some types of carbohydrates cause your child’s blood sugar to rise more quickly than others, so you may need to adjust insulin doses for different types of food.
It’s all on the label
If you’re counting carbohydrates, knowing how to read a Nutrition Facts label can make it easier. The 2 most important things to look out for when using a food label to count carbohydrates are:
- Serving size
- Total grams of carbohydrate
Are all carbohydrates created equal? Absolutely not!
Counting carbs alone may not give you the whole picture. Some carbohydrate-containing foods can cause a faster rise in blood sugar levels than others.
The glycemic index (GI) is a measurement of how much 1 kind of food will raise blood sugar levels. A food with a low glycemic index will cause a small and slow rise in blood sugar level. A food with a high glycemic index will cause blood sugar to rise faster.
The glycemic index is based on glucose, the carbohydrate that raises blood sugar the fastest. Glucose has a rating of 100. Foods are divided into 3 categories: high GI, medium GI, and low GI. They are ranked on how they compare to glucose.
When planning meals, it can be useful to try and choose foods that have a low or medium GI. If a meal does include a food with a high GI, try to eat it with a food that has a low GI. Doing so may help balance out meals.
High GI foods have a GI of 70 or more.
Some examples are:
- White bread
- Potatoes (boiled)
- White rice (boiled)
- Glucose (sugar)
Intermediate or medium GI foods have a GI between 56 and 69.
Here are some examples:
- Sweet potatoes (boiled)
- Pineapple (raw)
- Potato chips
Low GI foods have a GI of 55 or less.
Some of these are:
- Mixed-grain breads
- Legumes (such as chickpeas, beans, and lentils)
- Milk and yogurt
- Ice cream
Other things to keep in mind when using the glycemic index:
- While the GI indicates what type of carb a food contains, it does not take into account how many carbs are being eaten. So it is still necessary to pay attention to portion sizes
- Combining foods with different GIs may help balance out the effect on blood sugar
- Nutritious foods can still have a high GI, while foods with little nutritional value may also have low GI. For example, chocolate has a relatively low glycemic index (40), but its high saturated fat content reduces its nutritional value
While the GI can be a helpful way to compare or rank food choices, there is some debate as to how accurate or useful it is for blood sugar control. So before changing what you eat based on the GI, talk to your health care provider about how it may (or may not) be helpful for your child’s diabetes care plan.
Timing of meals and snacks
Generally, children with diabetes are advised to eat 3 main meals each day with 2 or 3 snacks in between. If your child is prone to low blood sugar, you may want to consider giving your child a complex, long-acting carbohydrate snack at bedtime.
Keeping to a routine with regular mealtimes, where the child and family sit down together to eat, has been shown to help improve blood sugar control, along with healthy eating and tracking food intake. Your child’s dietitian will help you to plan timing and content of meals to fit in with your child’s needs and insulin dosing.
Sometimes it can be hard to predict how much your child will eat, particularly if he or she is younger. You may find some days they are not hungry or are feeling ill, and so aren’t taking in their usual amount of food. Their insulin doses may need to be adjusted on these days.
Keeping a record
It may help to keep a record of what your child eats and their insulin doses. This will help you learn how different foods and activities affect blood sugar levels.
Some rapid-acting insulins can be given right before meals so you can work out the dose based on what is actually on their plate.
What about school lunches?
If your child is at school, you may find it easier to provide packed lunches and ask him or her to bring home anything uneaten. You may also want to write down the carbohydrate content for your child or school staff so they know how much carbohydrate your child should be eating.
If your child would like a hot lunch at school, you may be able to get a school lunch menu in advance so you can work out how many carbohydrates are in each dish. Speak to your child’s teacher or school nurse about your child’s specific needs and decide who will take responsibility for helping him or her at mealtimes.
At birthday parties, your child can still enjoy cake and other treats. You may, however, need to adjust the amount of other carbohydrate-containing foods (such as potatoes, bread, or pasta) your child has that day to compensate. Some physical activities at parties (like dancing and games involving movement) may also help balance out the treats eaten.