Calculating Your Carbohydrate Ratio

People with diabetes who do not calculate doses are typically prescribed a fixed amount of carbohydrate for each meal, and a corresponding fixed insulin dose e.g. Breakfast 30 grams, 3 units of insulin. To use PredictBGL, the fixed carbs and fixed insulin dose need to be converted to a carb ratio so that PredictBGL can use it. This only has to be done once and then transferred to PredictBGL under Settings\Dosing\Carb Ratio, in either the App or the website.

Your carb ratio determines how much insulin to use for ANY amount of carbohydrate. Your carb ratio can vary, particularly in the morning, where you generally require more insulin for the same amount of carbs compared to the rest of the day.

Calculating how much insulin you need for any amount of carbohydrate is quite easy. Just enter the carbs you have for each meal, and the fixed amount of insulin you usually have below.

Step 1. Enter Current Values

Food measurements

 

Meal name Fixed carbs? Fixed insulin?   Carbohydrate ratio is:
Breakfast  
Morning tea  
Lunch  
Afternoon tea  
Dinner  
Supper  

Step 2. Review

Now you need to check if your ratios are right.

If you get low after breakfast (test 2-3 hours after), then you are getting too much insulin. You need to increase the amount of carbs covered by easy unit, try increasing by 1 or 2 grams, and then test with the new ratio. However, if you are getting too high after breakfast (test 2-3 hours after), then you need more insulin. Try decreasing by 1 or 2 grams, and then test with the new ratio.

Predict blood sugars three hours ahead! Get live coaching to improve your ratios! Try ManageBGL now.

Available scenarios:

How does Low GI food affect my blood sugar?
Calculating Correction Ratio
Calculating Carbohydrate Ratio
Should I inject before my meal?
Afreeza versus Humalog/Novolog/NovoRapid
Lucy thought she was Low
Undiagnosed versus diagnosed Type 2 diabetic
Diabetes and Blindness

Suggestions for more scenarios? Please send them to us