If you need to keep an eye on your blood sugar levels, then you are no doubt closely watching the amount of carbohydrates you eat.
But here’s something you might not know…
Not all carbs are created equal.
Just because you know the number of grams of carbohydrates you’re eating doesn’t mean you know everything about how your body is going to respond. We digest and metabolize different foods differently.
The Glycemic Index is a useful tool for better understanding how your diet impacts your glucose levels. It can also help diabetics better manage their health.
What the Glycemic Index is & How it Works
It’s actually pretty simple. The Glycemic Index – or GI – ranks certain food items on a scale of 0 to 100 (or higher in some cases) based on how much potential the food has for making your blood sugar spike quickly.
The larger the number, the faster that type of food causes your blood sugar to rise. Typically, pure glucose is used as a reference point by which to compare everything else. Glucose is given a GI ranking of 100.
Other foods are grouped into High, Medium and Low GI based on their number:
- High GI Foods = 70-100+
- Medium GI Foods = 56-69
- Low GI Foods = 0-55
The GI number is determined after calculating the “available carbohydrates.” Those are the carbs your body actually digests and metabolizes. Some forms of carbohydrates – such as insoluble fiber – are non-digestible. It passes through your system without any caloric impact.
So to figure out the available carbohydrates, you would subtract the fiber from the total carbs in a normal serving size.
Researchers then examine how an individual’s blood sugar rises over a period of two hours after eating 50 grams of available carbs from a certain food item. Finally, that food is compared with how the body reacts to 50 grams of pure sugar – or glucose – as the reference.
Health experts have discovered that examining food this way can be important. Too often we assume things about what we eat and end up being incorrect. For instance – would you expect potatoes to have a higher GI number than honey? They do. Potatoes have a higher Glycemic Index than table sugar!
Most diabetics use some form of carbohydrate counting to understand the effect their meal will have on their sugars and to know how much insulin should be taken.
The Glycemic Index is not a replacement for counting carbs, But it can be a useful guide to reference in addition to counting the carbohydrates in a meal. Here’s what the American Diabetes Association says…
“Because the type of carbohydrate can affect blood glucose, using the GI may be helpful in ‘fine-tuning’ blood glucose management. In other words, combined with carbohydrate counting, it may provide an additional benefit for achieving blood glucose goals for individuals who can and want to put extra effort into monitoring their food choices.”
The Glycemic Index isn’t perfectly accurate either. The combination of foods you eat can also have an effect on glucose levels. For example, a meal that’s high in fat can cause your blood sugar to rise slower than a low-fat meal, and as a result a spike will come later. But the GI only takes carbohydrates into account and the result of fat content is not considered.
Variations in GI can also occur because of things like the ripeness of a fruit or the cooking method used to prepare food.
Factoring in the Glycemic Load
Another potential fault of the Glycemic Index is that it only shows you the speed at which foods cause your blood sugar to rise.
It doesn’t actually tell you much about how many carbs are in something – which can cause confusion. Remember – the test uses 50 grams worth of carbs for everything. But you need to eat different amounts of different foods to equal 50 grams of carbohydrates.
Watermelon is a food that’s fairly high on the Glycemic Index – its sugars are easily broken down and it effects glucose levels rather quickly. But there is a relatively low amount of total carbs in your typical serving of watermelon.
Some food isn’t even tested using the GI simply because you’d have to eat so much of it just to equal 50 grams of carbohydrates. As diabetic health writer David Mendosa explains…
“The problem is a technical one for the testers, because they would be so hard put to get anyone to volunteer to eat 50 grams of carbohydrate from celery—it’s just too much celery to think about!”
Glycemic Load (GL) takes the GI and uses it in a formula that also involves available carbs. It works like this…
GLYCEMIC LOAD = GI Number multiplied by Available Carbohydrates and then divided by 100.
So if something had a GI of 70 with 10 available carbs per serving, it would be 70 x 10/100 = 7 GL.
- Want more help? Check out How to Calculate Glycemic Load for Dummies
Foods are also broken down into High Medium and Low Glycemic Load:
- High GL = 20 or higher
- Medium GL = 11-19
- Low GL = 11 and lower
So in the example above – that food item would be considered High on the Glycemic Index (raises blood sugar quickly), but Low on Glycemic Load.
Glycemic Load also has more flexibility than GI. It allows you to determine the GL for any portion size. In fact, you can use the formula to calculate the Glycemic Load of an entire meal or everything you eat in a day.
You wouldn’t want to avoid healthy foods with a high GI – like some fruits and vegetables. Determining the GL can paint a clearer picture.
Choosing Your Food Based on GI and GL
The Glycemic Index and Glycemic Load can be used for more than just managing diabetes. Many people use them as tools for healthier eating, low-carb dieting and to promote weight loss.
Some say using the GI can lead to improved energy levels and reduced stress. That’s because meals high in carbohydrates cause your blood sugar to spike – and then you crash. That’s what makes you feel fatigued and experience mood swings after consuming unhealthy stuff.
We’ve put together an infographic featuring 20 common foods and their GI/GL rank. Check out the resources mentioned at the end of this post for even more information on the Glycemic Index and your diet.
Supplements and Natural Health Products That Could Help
A dietary supplement like Lo-Glycemix could help convert high glycemic index foods to low glycemic index foods.
It is formulated to help your body slow down digestion and metabolizing of carbohydrates. Lo-Glycemix from Pure Encapsulations includes a proprietary fiber blend, iodine and brown seaweed.
There are also herbal supplements such as Sugar Balance from Organic India. It may reduce the effective glycemic index of foods while balancing energy levels and curbing your cravings for sweets.
And of course, you can also order natural sweeteners that may be beneficial to those with diabetes.
If you do choose to add supplements that can effect blood glucose, make sure to discuss them with your doctor or diabetic educator and closely monitor your blood sugar levels.
You can visit GlycemicIndex.com for a lot more information on how to use the GI. There is even a search function to help you look up specific types of food. You’ll also find meal plans and articles detailing the latest research.
Check out Mendosa.com for a much more extensive list of foods and a look at their Glycemic Index and Glycemic Load. You can also find a list of more than 100 foods on the website for Harvard Medical School.
Watch a Video Explaining the Difference Between the Glycemic Index and Glycemic Load
Featured Image Credit – Jonny Wilkins via Flickr