The glycemic index (GI): some swear by it, while others brush it off as insignificant. Although it has been around since 1981, the debate surrounding its use and effectiveness continues to divide experts.
Understanding the Glycemic Index
In simple terms, the glycemic index measures how much a food containing carbohydrates raises blood sugar levels. It represents the percentage of increase after consuming an amount of food that supplies 50 grams of carbohydrate. The scale ranges from 0 to 100, with pure glucose receiving a rating of 100. A GI of 55 or less is considered low, 56-69 is medium, and 70 or more is high. To find a food’s GI ranking, you can visit glycemicindex.com.
The Importance of the Glycemic Index
Why does this matter? Some experts argue that the average GI of our diet can indicate the risk of developing heart disease and type 2 diabetes. Research suggests that following a low GI diet can reduce the risk of certain cancers, stabilize blood sugar levels, enhance mental performance, boost energy, and even help reduce inflammation in the body’s cells, which is linked to various health conditions. Many people turn to the glycemic index to manage blood sugar levels or maintain a healthy weight.
The Controversial Rankings
Sugary foods and highly processed carbohydrates, like those made with white flour, tend to rank high on the glycemic index. Conversely, whole foods such as fresh fruits, vegetables, and whole grains generally have lower rankings. However, it gets tricky because some extremely healthy foods have higher rankings than less nutritious, processed options. For example, carrots have a GI ranking of 92, while ice cream sits at 37.
Multiple factors influence a food’s GI rating. The presence of fat, fiber, and protein in the food can slow down carbohydrate absorption, affecting the GI. Other factors include the food’s acidity, preparation method, and cooking time. Additionally, the size of food particles plays a role. Mashed potatoes, for instance, have a higher GI than a whole baked potato, and instant oatmeal has a higher GI than rolled oats.
The Ice Cream Paradox
Now, let’s address the issue of ice cream having a lower GI ranking compared to carrots. Remember that each food is tested after consuming enough to provide 50 grams of carbohydrate. In a serving of 1.5 cups of ice cream, you consume 50 grams of carbohydrate, which is a reasonable amount for many. Furthermore, ice cream contains a significant amount of fat, which lowers its GI rating. On the other hand, it would take a whopping 70 baby carrots to reach the 50-gram carbohydrate mark. Who could devour 70 baby carrots in one sitting?
Another factor impacting the GI ranking is when a food is consumed alongside other items. For instance, if you eat a regular portion of carrots with a meal containing chicken and rice, your blood sugar won’t experience a significant impact.
With so many factors influencing the blood sugar response, it’s no wonder the glycemic index remains highly controversial. In fact, the 2015-2020 Dietary Guidelines for Americans don’t mention the glycemic index at all, suggesting it may not be crucial for the average healthy person.
In my practice, I always advise clients to focus on consuming wholesome carbohydrates like whole fruits, vegetables, whole grains, and low-fat dairy products such as milk and yogurt. Limiting added sugars to a maximum of 25 grams per day for women and 37 grams per day for men is also essential. Rather than relying on a complex ranking system, simply choose nutritious and wholesome foods, and let the rest fall into place.
Susie Bond is a Registered and Licensed Dietitian/Nutritionist with Health First Pro-Health & Fitness Center. Contact her here.