When you choose a food to eat, do you read the label first? If you’re like many people, you might glance at the servings per package, total number of calories, or added sugar, but ultimately, most of us choose to eat the foods we like. For individuals with diabetes, however, every meal or snack requires careful calculation to ensure their blood sugar remains stable, and one tool commonly used in this process is the glycemic index.
The Glycemic Index: A History
The concepts underlying the glycemic index were first introduced by a group of researchers in the pages of The American Journal of Clinical Nutrition in 1981, and the goal of the study was to measure blood glucose changes after the consumption of different foods. Though the initial study was quite small and looked at just 62 common foods, this work forms the foundation of a now substantial body of research and generated a useful diet management tool, not just for diabetics, but for everyone.
Measurement Basics
Since the original research was published, many others have built on the concept of the glycemic index such that we now have a clear sense of what foods have a high glycemic index. Food in this group cause substantial fluctuations in blood glucose levels over a short period of time, while those with a lower glycemic index cause little or no fluctuation.
Using a scale of 1 to 100, foods with a glycemic index under 55 are considered to have a low glycemic index, while, foods with a value of 70 or more are considered to have a high glycemic index. You can use a glycemic index chart to identify foods with a low glycemic index, though foods with no carbohydrates have a glycemic index of 0 and pure sugar forms the top of the scale at 100.
Why Go Low GI?
While there are obvious benefits to a low glycemic diet for those with diabetes and some other health conditions, but why should others consider the diet? There are a number of proven benefits to eating a diet with a lower glycemic index, including:
- Increased Energy: Did you know that many of the foods favored for breakfast in the United States have a high glycemic index? These include foods like corn flakes (81), Cheerios (74), and wheat bread (70). Even worse are foods like waffles and pancakes topped with faux-maple syrup, which is essentially pure sugar. Foods like this cause your blood sugar to quickly spike and then plummet, which can leave you feeling tired all day, while eating a small amount of a high glycemic index food in combination with one lower on the scale, such as eggs or fruit, can make a big difference in both energy and satiety.
- Weight Loss: Every day there’s a new headline about the obesity epidemic in the United States, and one issue that has stymied doctors and nutritionists is that, while Americans have largely reduced their fat consumption to around 30% of dietary calories, they continue to gain weight. Eating a low glycemic index diet, then, may be key to sustained weight loss on a larger scale.
- Reduced Cancer Risk: Cancer is a complex disease, and virtually all cancer occurrences are dependent on multiple factors. That being said, when adjusting for factors like socioeconomic status, BMI, age, and certain medications, among others variables, researchers have found a direct link between high glycemic index diets and colorectal cancer. As with other dietary factors that influence colorectal cancer risk, the more processed the high glycemic index food, the greater the cancer risk.
- PCOS Management: Polycystic ovarian syndrome (PCOS) is an endocrine disorder that affects as many as 5 to 10% of women of childbearing age, though it is generally underdiagnosed. Because of its impact on hormone production, PCOS can also cause an increased degree of insulin resistance, which can lead to lifelong metabolic problems and make women with this condition more likely to be overweight or obese. When women with PCOS are prescribed metformin alongside a low glycemic index diet, however, they see a greater improvement on insulin resistance tests than those who follow a healthy diet without metformin or consideration for glycemic index.
- Lower Heart Disease Risk: Insulin resistance and other manifestations of metabolic disease are linked to greater risks of cardiovascular disease, even as we tend to focus on issues like saturated fat or sodium content in this regard. What’s overlooked here is that high glycemic index diets have less healthy fat profiles on lab tests than those consuming low glycemic index diets. Low glycemic index foods seem to actively prevent de novo lipogenesis, however, lowering patients’ risk of various cardiovascular issues. Such a connection makes sense given the additional link between heart disease and obesity.
Low Glycemic Index: It’s Not The Only Factor
Understanding the impact of glycemic index on your overall health is valuable, but at the end of the day, it’s not the only factor you need to consider in order to consume a healthy and balanced diet. Rather, it’s important to balance high glycemic index foods with much a much lower glycemic index because glycemic load – a factor that is related, in part, to the amount of food consumed – is also a critical factor in how your body processes foods. Furthermore, many healthy foods, such as starchy vegetables, have a high glycemic index, but that doesn’t mean they aren’t good for you. As with everything in the world of nutrition, the rule is all things in moderation.
Learning to use a glycemic index chart can help you make wise decisions when planning your meals, but you should always consult your doctor before making major changes to your diet as individual needs vary. While most diabetics will make extensive use of the glycemic index to manage their blood sugar, individuals with no underlying conditions or who have a very different health profile may require a different set of modifications for optimal health.