University of Illinois Extension

Coordinating Diet and Exercise with Diabetes Treatment

In children who already have diabetes, diet and exercise need to be carefully coordinated with the medication regimen to maintain target blood glucose levels.

Physical Activity

Here are some things that need to be considered when incorporating physical activity into diabetes treatment.

  • Talk to the child's doctor first about the types of physical activity that might be best.
  • If the child has not been active in the past, they should start with just a few minutes each day. They shouldn't get upset if they can't do very much at first, but any amount of activity helps.
  • Get the child’s blood pressure checked before they start any very active play.
  • Blood glucose and blood lipids should be monitored and within a normal range.
  • If the child has type 1 diabetes and is taking insulin, you need to make sure that the blood glucose level doesn’t get too low during or after activity. In case of a hypoglycemic emergency, they should have a medical ID bracelet. Read more about this in “Hypoglycemia.”

Diet Therapy

Diet therapy for individuals with diabetes may be overseen by a registered dietitian (RD). Treatment will be personalized for each child, but some of the terms encountered might include “carb counting” and “carb units.” Keep reading to learn more.

Carbohydrates are found in almost every food. What do they have to do with diabetes? Carbohydrates contain glucose. They also cause blood glucose to rise faster and higher than protein or fat do. Some foods with added sugar like cakes, cookies, or candy can contain a lot of carbohydrate per bite. Compact foods like granola or dried fruit are also higher in carbohydrate on a volume per item basis. Do they have to be avoided? No, but they have to be counted.

Some carbohydrates cause blood glucose to rise more quickly and have a higher peak. Liquid carbohydrates are more quickly digested and absorbed than solid food. Milk and fruit juice may cause blood glucose to go higher and faster than other starchy foods. This is important to remember for children who drink a lot of fruit juice.

Most carbohydrates are digested and absorbed with 2 hours of eating. This is usually when a post-prandial (after meal) blood glucose value would be taken. Monitoring both before and after blood glucose is very important until the meal pattern becomes a habit.

Carb Units

Carb units are used with carbohydrate counting. Fifteen grams of a high carbohydrate food is counted as one carbohydrate serving or unit. High carbohydrate foods that we count are starches, milk, and fruit. Other foods aren’t counted since they don’t have 15 g of carbohydrate per serving. These include most green leafy vegetables, meats, and cheeses.

How many carbohydrates does a child need? About half of the child's daily calories need to come from carbohydrates and there are 4 calories in 1 gram of carbohydrate. Remember that 15 grams of carbohydrates are approximately equal to 1 carb unit. Divide the total grams of carbohydrate per day by 15 grams to find the number of carb units that can be spread throughout the day. We divide that into 3 meals, to find out how many carb units the child is receiving per meal. We then match the carb units to the insulin units to keep blood glucose in the right range.

Example

Remember our 13 year old boy?

  1. Let's say he needed 1400 calories. Remember, half of those calories should be from carbohydrates.
    1400/2 = 700
  2. Next we need to translate calories to grams. There are 4 calories in 1 gram of carbohydrate.
    700 calories x (1 gram/4 calories) = 175 grams of carbohydrates
  3. How many carb units does the child need?
    175 grams of carbohydrates x (1 carb unit/15 grams of carbohydrates) = about 12 carb units
  4. How should the carb units be spread out?
    12 carb units/3 meals = ~4 carb units per meal

For practive with carb units, go to Carbohydrate Counting in Games and More

Matching Carbohydrates to Insulin

The ratio of carb units to insulin units varies with individual sensitivity. While most adults need 1-3 units of insulin for one carb unit (15 grams of carbohydrate), the child may need less than that to begin. Much of the variance in the carb to insulin ratio may be related to the person's weight. Children who weigh less may need less than 1 unit of insulin per carb unit.

A key to figuring out the right insulin to carb ratio is in blood glucose monitoring. If a child is just starting insulin therapy, it’s usually recommended to test blood glucose four times per day. Those four tests per day may be before breakfast or just upon rising, before the other two meals and after one of the meals.

However, if the child is very young or does not recognize when they have low blood glucose, 3 a.m. tests may be the key in determining basal insulin needs; 3 a.m. tests allow the parent and the physician to see if the basal insulin is too high. If it is, there will be a dip in blood glucose levels early in the morning.

The amount of insulin needed can be anywhere from 0.3 units/kg to 1 unit/kg, but the average is 0.3-0.4 units/lb or 0.7 to 0.9 per kg. Insulin dosage may need to be adjusted if there is a change in food intake or physical activity. Insulin may also need to be adjusted during illness.