Glycemic Index

Important for everyone but even more so for those with a sweet tooth!

Today’s discussion will be centered around the topic of glycemic index (GI)– something many may be familiar with but are still unsure what it means and the implications it has on our health. Quickly, glycemic index is simply defined as how rapidly a food causes an increase in the blood sugar levels of the consumer. We are all probably familiar (especially those living with or know someone with diabetes) with the idea that carbohydrate-rich foods increase our blood glucose levels…but what does that mean and what are the consequences?

Glucose and Insulin

I assure you that this will be the only science lesson of this article and it will be easy to follow if you stick with me. The amount of sugar we have in our bloodstream, referred to as blood glucose, is a very important aspect of our health and the ability to do the things we do. Our bodies need glucose because it is our main source of ‘fuel’, however, our blood glucose levels must be kept in a tight range as levels too high or low can have deleterious effects. Ask anyone living with diabetes about their episodes of hypo/hyperglycemia and they will confirm this point. For glucose to have its effect, a hormone called insulin must also be present. Think of insulin as the key that opens the lock to allow glucose to enter through the door and go to work. Without it, glucose serves no purpose and is instead very harmful to our health.

A very common saying that applies to many things in life and particularly blood glucose levels is “too much of a good thing is a bad thing”. When our blood sugar levels become too high, insulin is overwhelmed and has a hard time allowing all of this excess glucose through the door which can lead to immediate symptoms like blurred vision and excessive urination. More important is the long-term detrimental impact high blood glucose has on our blood vessels which accumulates over time and can lead to cardiovascular disease, nerve damage, kidney issues, and many other preventable diseases. I’ll stop here and return back to the planned programming but you’ll see how this ties into today’s discussion on the glycemic index of foods.

Glycemic Index – Measurement & Importance

A food’s glycemic index is placed on a scale of 0-100. A score of 0 means that the food has no effect on blood sugar levels whereas a score of 100 means the food has the same effect that pure glucose (sugar) has when eaten by itself. Foods that are lower on the scale have a more gradual, longer lasting increase in blood glucose levels which makes insulin’s job easier whereas foods higher on the scale create a rapid spike that is shorter in duration. Specifically, low GI foods fall in the range of 0-55, medium GI foods are considered 56-69, and anything higher than 70 on this scale is considered to have a high GI. Below is a table to familiarize yourself with the scale and where certain foods fall. A quick Google search will tell you almost every food’s GI so use it to your advantage!

The most important part of this post is why higher GI foods are best kept to a minimum and only consumed at certain strategic times. In a study comparing multiple groups of people, it was discovered that the group consuming, on average, the lowest glycemic index foods had a 90% (!) less likelihood of developing Type 2 diabetes than the group consuming the highest (1). Read that again, a 90% less likelihood of being diagnosed with one of the world’s most debilitating diseases. Other research has time and time again demonstrated that prioritizing consuming lower glycemic index foods improves lipids (cholesterol & triglycerides), decreases inflammation, and is a great tool for weight management (2) . Although this information is beneficial to ALL people, it’s especially important for those currently living with Type 2 diabetes or pre-diabetes as these individuals already have disruptions in their sugar metabolism.

Circling back to the table above, you may have been surprised to find some of the foods we tend to think of as healthy (e.g., watermelon), are fairly high on the GI list. It’s important to note here that the glycemic index does NOT factor in the total amount of carbohydrates in the food itself. This means that although watermelon is higher on the list than cereal, the amount of carbohydrates per serving of food is much greater in cereal (for most brands) so you must be mindful about this aspect.

However, it is true that watermelon (and other fruits) have high glycemic indexes and therefore should be consumed in moderation while using the strategies below to limit their impact on spiking blood sugar levels! Furthermore, certain foods on the list such as oatmeal are not specific to the many different types (instant, whole grain, steel cut) so make sure you search specifically for the type you plan to consume for a more accurate estimation!

What does this mean for you?

1. Strategize Timing of High GI Foods

The first tip is to strategize when you consume foods that are higher up on the glycemic index list. Two of the best times to incorporate these foods are prior to and after exercising. For optimal performance, our bodies need fuel (glucose) to support the demands that we put on them during exercise. Eaten anywhere from 30-60 minutes before activity, higher GI foods can be a good choice to provide the body with this fuel. On the flip side, our bodies are much more capable of controlling our glucose levels following exercise due to the muscles becoming better equipped to take up the excess sugar – they become ‘hungry’ for glucose in a sense. Choosing to eat a higher GI food such as a baked potato is a good option in this scenario assuming the exercise was of sufficient intensity!

2. Intelligent Pairing of Foods

As mentioned previously, the glycemic index of foods is measured when eaten ALONE, however, it’s altered when other foods are added in. This is very important when it comes to our discussion because incorporating protein (and some fat) with higher GI foods slows their digestion and blunts the glucose spike mentioned previously. Instead of eating just cinnamon sugar toast for breakfast, pair it with a spinach omelette for better blood glucose control!

3. Movement After Meals

Another key tip to offset some of the effects that higher GI foods have on blood glucose levels is to move after your meals! Although for some reason it’s become popular to turn into a hibernating bear after a big meal, this is actually detrimental and research has shown that even walking as little as 2 minutes following a meal improves blood glucose levels and enhances digestion. This is even more applicable for those that often experience bloating and stomach distress after meals! Any type of exercise is fine including simply moving around your place of living! An upcoming post will dive into the science and more extensive benefits of incorporating movement after meals so stay tuned!

If you have any questions about glycemic index, drop them in the comment box below!

Citations:

1.     https://www.mdpi.com/2072-6643/12/2/536

2.     https://pubmed.ncbi.nlm.nih.gov/20234030/

Quote of the week:

“It is health that is real wealth and not pieces of gold and silver.” – Gandhi

DISCLAIMER

-       This is NOT Medical advice. Consult your medical professional before starting any supplement, diet regimen, or workout program.