After eating, everyone experiences a temporary rise in blood sugar as the glucose from food enters your blood stream. This blip is barely noticeable in healthy individuals. However, when you have diabetes, food digests faster than normal and these post meal (post prandial) spikes and subsequent dips can be dangerous.

In the short term, spikes decrease energy, affect brain function, diminish physical abilities, and alters mood, says Gary Scheiner, a certified diabetes educator at Integrated Diabetes Services. Over time, multiple spikes raises patients' overall average blood sugar.

Significant post-meal rises have been shown to:

  • Produce early onset of kidney disease
  • Accelerate progression of existing eye problems in people with type 1 diabetes
  • Are an independent risk factor for cardiovascular disease in type 2 diabetes

How much blood glucose levels rise or fall depends on how much you eat, what you eat, and the amount of mealtime insulin in your blood. Here are a few guidelines:

1. Choose foods carefully

  • Foods high in fiber digest more slowly and blunt blood glucose increases.
  • Solids, cold food, and whole foods digest more slowly than liquid, warm, or processed foods.
  • Avoid foods with added sugar.
  • Eat carbs with foods that contain fat or protein since they cause blood sugar to rise more slowly.
  • Choose foods with lower glycemic index, which raise blood sugar at a slower rate than those with a high glycemic index; they are less likely to cause spikes. According to the American Diabetes Association (ADA), glycemic index can vary for the same food depending on the source and how it's prepared.

However, foods with lower glycemic index are not necessarily healthier, so choose whole foods that are natural, raw, and unprocessed.

2. Change portion sizes

Adjusting portion sizes allows you to still eat the foods you want. Scheiner suggests splitting your meal and saving a portion of it for a snack one to two hours later.

3. Move

A short walk after eating will help burn excess glucose by diverting blood to your muscles and slowing digestion. Avoid sitting for an extended time after eating.

4. Adjust your medications

Scheiner recommends adjusting insulin doses depending on what you are eating and your pre-meal blood sugar. For example, he says, research shows giving meal time bolus before eating rather than after can reduce post meal spikes significantly. Work with your diabetes health professional to safely adjust dose and timing of medications.

5. Keep track

A journal will help you monitor how food, exercise, stress, and other factors affect your blood sugar so you can spot trends and make changes if needed.

Allison Massey, MS, RD, LDN, CDE, reviewed this article.


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