Diabetes Bites Newsletter

JENNY'S journalJenny’s Journal:

How to Adjust for Fiber When You Have Type 1 Diabetes

good fiber sourcesFiber is good for the body for many reasons. Does this need to be considered when we eat meals high in dietary fiber? Should there be any insulin adjustment when we have a meal with more fiber?

What is fiber?

Fiber is a type of carbohydrate that is made of both soluble and insoluble components. Soluble fiber is the kind that gets sticky in oatmeal and is good for helping to pull fats out of the digestive system to be eliminated when we go to the bathroom. Our body does digest soluble fiber so it’s important to take this into consideration when counting carbs at a meal. Insoluble fiber is the roughage that we get from many vegetables and true whole grains. This type of fiber doesn’t get digested, so we do not have to “count” this type when calculating carbohydrates at a meal or snack.

How do you know how much soluble versus insoluble fiber is in a particular food?

The breakdown is about 50/50 for most high fiber foods. When you look at a food label, first look at Dietary Fiber – this is the total amount of both soluble and insoluble fiber in the food.  When calculating the carbohydrates that you’ll use to dose your insulin, you can subtract 50% of the total dietary fiber off of the total carbohydrate. Try to do this when foods have at least 5 grams of fiber or more per serving.  Subtract 50% for the insoluble fibers that will never effect our BG.

~ Some labels already have the breakdown of soluble vs insoluble fiber – if this is the case, deduct the noted insoluble fiber from the total carb count.

How to adjust your insulin?

Consider that high fiber foods may slow the digestion of other carbohydrates and nutrients at that meal. This helps to minimize post-meal blood sugar spikes. It is often necessary to delay mealtime insulin when consuming meals that are high in fiber or low glycemic (such as beans or a large vegetable salad).

If you use injections this may mean you take your injection mid-meal or even at the end of the meal.
If you use an insulin pump, it may be beneficial to learn how to use your extended bolus feature to accommodate for high fiber foods and the slower digestion.

What are good sources of fiber?

Good sources of fiber include delicious fresh fruits and vegetables, whole grains, legumes, bran, nuts and seeds.