Tips to Avoid Post-Meal Spikes in Your Blood Sugar


One of the most challenging parts of managing your diabetes is keeping your blood sugar in your goal range after a meal. For people with diabetes, trying to match the timing of your insulin with the digestion of your meal is never simple.

While there are certainly a variety of strategies that can help, it’s often hard to know which strategy to use or how to realistically apply them to real life with diabetes.

Here are three tips that may help you prevent a big post-meal spike in your blood sugar. Of course, patients should always consult with their medical provider before making changes to their diabetes management.

1. The mighty pre-bolus

If you’re taking fast or rapid-acting insulin via pen/syringe/pump/inhaler, the “pre-bolus” is the standard recommendation for meals that are moderate in carbohydrates, dietary fat and protein.

A pre-bolus means you take the insulin dose for your meal approximately 5 to 15 minutes before eating because today’s fast or rapid-acting insulin takes 15 minutes to start working in your bloodstream after injection. This insulin’s action on your blood sugar also peaks at approximately one hour after injection.

The goal here is to time the action of your insulin with when the majority of your meal is digested and hitting your bloodstream. By giving your insulin a head start in your system, it can prevent that post-meal spike and help you stay within your goal range.

When pre-bolusing won’t help: Pre-bolusing works well for meals that are moderate in carbohydrates and low-to-moderate in fat and protein, but it can be dangerous for other types of meals. If you’re eating a high-carb/high-fat meal (like pizza, cake, Chinese food, etc.), a pre-bolus can lead to a severe low within the hour or two after eating because these meals often take many hours to digest.

Pre-bolusing is also likely unnecessary and unsafe if you’re eating a low-carb/high-fat/high-protein meal because the digestion of the fat and protein is slow and the digestion of the minimal carbohydrates will be slower, too.

Talk to your healthcare team to determine when pre-bolusing is right for you.

2. Try inhaled insulin

Inhaled insulin is one of the lesser-known strategies to improve mealtime control.

  • It starts working fast—within 12 minutes
  • It’s out of your system within one-hour-and-a-half to three hours, depending on the dose

Using inhaled insulin with your meals means you don’t need to worry about pre-bolusing, which is especially helpful if you can’t always predict when you’ll eat—like when ordering at a restaurant, or fitting mealtime into a hectic work schedule.

Talk to your healthcare team about adding inhaled insulin to your diabetes toolbox!

3. Go for a walk after the biggest meal of the day.

Walking after your biggest meal of the day can have a big impact on those post-meal highs, but knowing how to add it to your routine safely takes some careful thought.

If you don’t take mealtime insulin, a 15 to 30-minute walk after eating is a generally safe way to help your body burn up the carbohydrates from your meal.

If you take long-acting insulin or other medications that can cause hypoglycemia (low blood sugar), you should always carry fast-acting carbohydrates with you, like juice, glucose tabs, or jelly beans.

Talk to your healthcare team about safely adding a post-meal walk to your diabetes management regimen.

WRITTEN BY Ginger Vieira, POSTED 10/27/21, UPDATED 03/14/24

Ginger Vieira is an author and writer living with type 1 diabetes, celiac disease, fibromyalgia and hypothyroidism. She’s authored a variety of books, including “When I Go Low” (for kids), “Pregnancy with Type 1 Diabetes,” and “Dealing with Diabetes Burnout.” Before joining Beyond Type 1 as digital content manager, Ginger wrote for Diabetes Mine, Healthline, T1D Exchange, Diabetes Strong and more! In her free time, she is jumping rope, scootering with her daughters, or walking with her handsome fella and their dog.