What are insulin spikes?

Happy Thanksgiving everyone! Just a quick reminder that CFC will be having classes at 9:00 AM and 10:00 AM on both Thanksgiving and Black Friday this week, to help you earn your way to that turkey & stuffing dinner!


Today we’re talking about insulin spikes, and how they affect your health and fitness.

What are insulin spikes?

Many of the most common foods we eat have a moderate to high level of carbohydrate content. Some of those carbs are simple, like table sugars and candies, while others are complex, like whole oats. When you eat carbs, your body digests them into their component sugars – typically glucose or fructose – and those sugars are shunted around the body to be used in other areas. Glucose goes directly into the blood stream to be used for energy, while fructose takes a more roundabout way through the liver where it is processed into glucose, and then shunted into the blood stream. When the sugars reach the blood, your aptly named Blood Sugar Levels go up and the body has to deal with it.

Enter the protein Insulin, which is released by the pancreas in response to increased blood sugar. When your body releases insulin into the blood we call it an “insulin spike”, and we could accurately say that’s it’s released in response to a “sugar spike”.

This action is natural, but it can also “wear out” when too many carbs are eaten too often. Over time, excessive intake of sugars can lead to perpetually high blood insulin levels, and the body starts to become insulin resistant. This leads to poor functioning and, eventually, the body stops producing it completely. This is called type-2 diabetes and it’s bad, mm’kay?

What do insulin spikes actually do?

Insulin acts as a messenger molecule that tells muscle and fat cells to “open up” so they can use the sugars floating around in the blood stream. For muscles this equates to more energy being available for movement that the body is currently doing. This can be helpful when you are having a pre-workout protein/carb shake, so that your muscles have all the “oomph!” they need to get the work done.

The down side to insulin, though, is when your levels spike and the muscles don’t need the energy floating around available to them. If the muscle in the body can’t seem to make use of the blood sugar, the insulin response will instead open up the fat cells in your body. We evolved to conserve energy as much as possible because for the majority of human existence we never really knew when the next meal was coming. The body, seeing all this free-floating energy not being needed, stuffs it into fat cells for later use. This way, the body figures, when we can’t find food we won’t starve!

Your body is a pretty awesome machine, but it doesn’t really understand the fact that there’s a grocery store right down the road where food is plentiful. You’ve likely heard about the “fight or flight” response, where adrenalin kicks in to either help you run or defend yourself. You can think of the insulin response as “feast or famine”, where the body is either gearing up to use energy or conserve it. If you’re active and food is coming regularly, you go into “feast mode” and your body uses what you eat. If you’re sedentary and food is plentiful, you go into “famine mode” and store the energy.

What can you do to manage blood insulin levels?

The two major ways to manage the insulin response so that it functions properly are:

  1. Reduce the carbohydrates you take in overall
  2. Eat more slow-digesting carbs and less fast-digesting carbs

The easiest way to help prevent insulin levels from going haywire is to simply take in less sugar in your diet. The less you eat, the less your body will need to release insulin to deal with it. While it may not be reasonable to completely cut carbs from your diet, you certainly do not need 50% or more of your calories per day coming from carbohydrates. Many people see a healthy, sustainable reduction in body fat by going down to 100 grams or less of carbs per day total, mostly pulled from low glycemic index (GI) carbs that digest slowly (see below). Your body can get the energy it needs from body fat and other dietary nutrients, so eating carbohydrates is pretty superfluous.

A good addition to cutting down on dietary carbs in general is to also eat foods with a low glycemic index. This is a measure of how quickly and how much your blood sugar levels will spike after eating a particular food. Things like white rice, white potatoes, and white bread all have very high GI values, thus causing big spikes very quickly. Better food choices are brown rice, whole oats, most fruits, and some nuts like cashews.

Whenever possible, choose low GI foods over high GI foods. You can use the awesome, searchable database maintained by The University of Sydney to help you plan your meals effectively. Go to http://www.glycemicindex.com to get started planning your healthy meals.

So that’s it! Have a healthy, happy, and safe holiday!