Wednesday, April 01, 2015

ASK GINGER - How do I figure out my insulin-to-carbohydrate ratio?

By Ginger Vieira, Health Guide Thursday, May 07, 2009

Hey Ginger, How do I figure out what my insulin-to-carbohydrate ratio? I’ve been guessing for a while, too long! And I want to be more precise. -Scott




Hey Scott! I’m glad you asked J It’s so important to know this, especially because you may have to determine what this ratio is again at different points in your life. Stress, diet, weight gain, activity level, age, etc. are all things that can change your insulin needs, but once you get an initial insulin-to-carbohydrates ratio, it’ll be easier to adjust it as you need to.


First off, here's one very common approach but it may not work for everyone. It's called the 500 Rule and there's a very good guide to it here. This method doesn't work for me as well, because I've found my body has much higher and almost illogical insulin needs in the morning, but it could be applied to later parts of the day. The 500 Rule implies you'll use th same ratio through the whole day.


For another approach...


How do you count carbs? For some carb-basics and knowledge, check these out:

Understanding Carbohydrates

The Carbohydrate Quiz


WHAT IS AN INSULIN-TO-CARBOHYDRATE RATIO? This is the amount of insulin you need to for a certain gram of carbohydrates. For instance, when I was first diagnosed and still in my “honeymoon phase” of producing a small amount of insulin, 1 unit of insulin would cover 15 grams of carbohydrates in my body. Today, I need more insulin, so during the middle of the day, 1 unit of insulin covers me for about 7 – 10 grams of carbohydrate.


At breakfast, I need A LOT of insulin because of all the hormones being produced when we get out of bed, and I use a ratio of about 1 to 4 (1 unit of insulin for 4 grams of carbohydrates). How did I figure this out? When my blood sugar was repeatedly high after a meal, I kept notes on how many carbs I ate and how much insulin I had taken, and gradually adjusted this amount until I saw my numbers where I wanted them to be. Lots of blood sugar checking! But only at first, once you determine your ratio, you won’t have to try nearly as hard to stay in range.

Step 1: Start with a level blood sugar. You need to start your experiment with a good blood sugar, having not done any heavy activity before or during (anything that will really effect your blood sugar).


Step 2: Count the carbohydrates in your meal precisely! Try not to use a meal of pizza or Chinese food, anything high in fat, that could cause your meal to digest more slowly. That is something you will adjust for later on after you know your true ratio. Eat a normal amount carbohydrates, like toast or cereal or fruit. It doesn’t have to be an entire meal, just something with at least 15 to 20 grams of carbs.


Step 3: Do the math!!! Counting carbs involves math. Non-diabetics don’t have to add and subtract before they eat lunch…we do. So, let’s say you’re going to begin with an estimated ratio of 1 to 12 (1 unit of insulin for 12 grams of carbs), and you’re eating a bowl of cereal for breakfast.

By Ginger Vieira, Health Guide— Last Modified: 01/23/12, First Published: 05/07/09