Insulin Ratios
What are Insulin Ratios?
Insulin ratios, also known as insulin-to-carbohydrate ratios (ICR), are a fundamental aspect of diabetes management.
An insulin ratio represents the amount of insulin needed to metabolize (metabolize means for your body to use as fuel) a certain amount of carbohydrates consumed, or as they are more often presented, the amount of carbohydrates than can be metabolized by one unit of insulin.
Insulin ratios vary from person to person and can even change for an individual over time based on factors such as activity level, stress, illness, and hormonal changes.
How to Use an Insulin Ratio
Often your doctor will provide you with an insulin ratio to use, or you may calculate your own (see below). Once you have your insulin ratio, you can now use it to determine the appropriate insulin dose for meals and snacks. When consuming carbohydrates, simply divide the number of grams of carbohydrates by your insulin ratio to find the amount of insulin needed.
For instance, if you plan to eat a meal containing 60 grams of carbohydrates and your insulin ratio is 1:4, you would require 15 units of insulin for that meal (60g / 4 = 15 units).
For another example, if you plan to eat a meal containing 100 grams of carbohydrates and your insulin ratio is 1:5, you would require 20 units of insulin for that meal (100g / 5 = 20 units).
Adjusting Insulin Ratios
It’s important to note that insulin ratios are a starting point and may need adjustment based on individual responses to insulin, blood sugar levels, and other factors. Regular monitoring and consultation with a healthcare provider or diabetes educator are essential for fine-tuning insulin ratios.
Several factors can influence insulin ratios, including:
Physical Activity: Exercise can increase insulin sensitivity, requiring less insulin to metabolize carbohydrates.
Stress: Stress hormones can affect blood sugar levels and insulin requirements.
Illness: During illness, insulin requirements may increase or decrease due to the body’s response to infection or changes in eating habits.
Hormonal Changes: Hormonal fluctuations, such as those occurring during puberty, menstruation, or pregnancy, can impact insulin sensitivity and ratios.
Regular monitoring of blood sugar levels and carbohydrate intake is essential for assessing the effectiveness of insulin ratios. If blood sugar levels consistently run high or low after meals, it may indicate the need to adjust insulin ratios. Consulting with a healthcare provider or diabetes educator can help identify the appropriate adjustments to insulin ratios based on individual needs and circumstances.
Easy Practice Problems
Below are some basic practice problems to help you get used to converting a certain number of carbohydrates into a certain number of units of insulin. The answers can be found after the problems.
Convert 40g of net carbohydrates into insulin using a 1u:10g insulin to carb ratio.
Convert 80g of net carbohydrates into insulin using a 1u:10g insulin to carb ratio.
Convert 16g of net carbohydrates into insulin using a 1u:4g insulin to carb ratio.
Convert 50g of net carbohydrates into insulin using a 1u:5g insulin to carb ratio.
Convert 64g of net carbohydrates into insulin using a 1u:8g insulin to carb ratio.
Convert 49g of net carbohydrates into insulin using a 1u:7g insulin to carb ratio.
Convert 21g of net carbohydrates into insulin using a 1u:7g insulin to carb ratio.
Convert 27g of net carbohydrates into insulin using a 1u:9g insulin to carb ratio.
Convert 10g of net carbohydrates into insulin using a 1u:5g insulin to carb ratio.
Convert 30g of net carbohydrates into insulin using a 1u:10g insulin to carb ratio.
Click to show answers
4 units
8 units
4 units
10 units
8 units
7 units
3 units
3 units
2 units
3 units
Intermediate Practice Problems
Here are some more practice problems, but this time the amount of carbohydrates and ratios might not line up perfectly, so you'll probably have some decimals in the answers!
Convert 50g of net carbohydrates into insulin using a 1u:10g insulin to carb ratio.
Convert 85g of net carbohydrates into insulin using a 1u:8g insulin to carb ratio.
Convert 12g of net carbohydrates into insulin using a 1u:6g insulin to carb ratio.
Convert 20g of net carbohydrates into insulin using a 1u:3g insulin to carb ratio.
Convert 63g of net carbohydrates into insulin using a 1u:9g insulin to carb ratio.
Convert 40g of net carbohydrates into insulin using a 1u:5g insulin to carb ratio.
Convert 21g of net carbohydrates into insulin using a 1u:6g insulin to carb ratio.
Convert 24g of net carbohydrates into insulin using a 1u:3g insulin to carb ratio.
Convert 26g of net carbohydrates into insulin using a 1u:6g insulin to carb ratio.
Convert 60g of net carbohydrates into insulin using a 1u:10g insulin to carb ratio.
Click to show answers
5 units
10.63 units
2 units
6.67 units
7 units
8 units
3.5 units
8 units
4.33 units
6 units
Difficult Practice Problems
Now that you're an expert in converting grams of carbohydrates to units of insulin try these multi-part problems that require you to calculate the total daily dose of insulin using some of the hardest insulin ratios.
Calculate the total daily dose of insulin if the person dosed as follows:
Breakfast: 30g carbs at 1u:6g insulin carb ratio.
Lunch: 50g carbs at 1u:5g insulin carb ratio.
Dinner: 80g carbs at 1u:8g insulin carb ratio.
Calculate the total daily dose of insulin if the person dosed as follows:
Breakfast: 40g carbs at 1u:4g insulin carb ratio.
Lunch: 20g carbs at 1u:4g insulin carb ratio.
Dinner: 40g carbs at 1u:8g insulin carb ratio.
Calculate the total daily dose of insulin if the person dosed as follows:
Breakfast: 10g carbs at 1u:10g insulin carb ratio.
Lunch: 20g carbs at 1u:10g insulin carb ratio.
Dinner: 50g carbs at 1u:5g insulin carb ratio.
Calculate the total daily dose of insulin if the person dosed as follows:
Breakfast: 50g carbs at 1u:6g insulin carb ratio.
Lunch: 30g carbs at 1u:8g insulin carb ratio.
Dinner: 45g carbs at 1u:8g insulin carb ratio.
Calculate the total daily dose of insulin if the person dosed as follows:
Breakfast: 45g carbs at 1u:6g insulin carb ratio.
Lunch: 27g carbs at 1u:5g insulin carb ratio.
Dinner: 53g carbs at 1u:5g insulin carb ratio.
Bonus: Eleanor is using an insulin pump set to deliver a basal rate of 0.7u per hour. If she gave insulin boluses based on the following conditions, what was her total daily dose of insulin (for a period of 24 hours)?
Breakfast: 10g carbs at 1u:6g insulin carb ratio.
Lunch: 56g carbs at 1u:9g insulin carb ratio.
Dinner: 53g carbs at 1u:7g insulin carb ratio.
Click to show answers
Breakfast: 5 units
Lunch: 10 units
Dinner: 10 units
Total: 25 units
Breakfast: 10 units
Lunch: 5 units
Dinner: 5 units
Total: 20 units
Breakfast: 1 unit
Lunch: 2 units
Dinner: 10 units
Total: 13 units
Breakfast: 8.33 units
Lunch: 3.75 units
Dinner: 5.63 units
Total: 17.71 units
Breakfast: 7.5 units
Lunch: 5.4 units
Dinner: 10.6 units
Total: 23 units
Bonus
Breakfast: 1.67 units
Lunch: 6.22 units
Dinner: 7.57 units
Basal Rate: 0.7 units/hour • 24 hours = 16.8 units
Total: 32.26 units