8 Things that Can Affect Insulin Absorption

The way insulin is absorbed in the body can have a profound impact on blood sugar levels. If you have Type 1 or Type 2 diabetes and take insulin injections to control your blood glucose, it’s important to understand how to administer insulin and the factors that can affect its rate of absorption.

1. Amount of insulin

This one is obvious, but critical. The more insulin you administer, the more there is for your body to absorb. Too much insulin can lead to hypoglycemia (when blood sugar is too low), while too little can result in high blood glucose. If your doctor makes changes to your insulin dosage, be sure to test with a blood glucose monitor to figure out if it’s where you need it to be.

2.Type of insulin

Different types of insulin vary according to their onset (how long it takes the body to absorb insulin) and duration (how long the insulin stays in the bloodstream). Depending on the type of insulin you take, you generally want to inject it right before you eat a meal, or 20 to 30 minutes prior. That’s because insulin should peak as your food starts to digest (when the glucose from food enters your bloodstream).

3. Location of injection

Where you administer insulin injections affects its absorption rate. Insulin is absorbed the fastest when injected in the less-fatty part of the abdomen. Absorption rates are slower in the arm, even slower in the leg and slowest in the buttocks. To avoid the build up of scar tissue, try to inject in a different spot each time.

4. Exercise

Exercise can affect both the absorption rate of insulin as well as your sensitivity to insulin. Exercise typically increases your sensitivity to insulin so that you need less of it, but sometimes intense exercise can actually spike blood sugar levels and decrease insulin sensitivity. The best thing to do is to monitor your blood glucose before, during and after your workouts to determine how exercise influences your need for insulin.

5. Food

The type of food you eat doesn’t change the rate at which insulin is absorbed into the blood, but it does affect your blood sugar levels.

For example, foods high in carbs and sugar (high glycemic foods) are absorbed quickly by the body, which can raise blood glucose if insulin has not had time to enter the bloodstream.

On the other hand, fatty foods are absorbed slowly, and your insulin may run out before the food is absorbed.  

That’s why the timing of meals is important relative to when insulin is administered.

6. Hydration

If you are dehydrated, it takes longer for blood to reach your skin, which can slow the absorption rate of insulin. That’s why it’s important to drink plenty of water, especially if you have diabetes and take insulin.  

7. Heat

Heat increases the size of blood vessels, which can increase the rate at which the body absorbs insulin. It’s best to inject insulin when your body is at its normal temperature, as opposed to when it is overheated from exercise or a hot shower. Taking insulin when you are hot could cause you to have a low blood sugar reaction.

8. Insulin storage

The way you store insulin affects its stability, and exposure to extreme heat or cold can affect its absorption rate. Opened vials of insulin can typically be kept at room temperature, but unopened vials should be kept in the refrigerator.

Being mindful of these factors will increase the effectiveness of insulin and help you regulate your blood sugar levels more effectively.