Watching Your Sugar? A New National Glycemic Index Makes It Easier Than Ever Before

What if the same food that spikes one person’s blood sugar barely affects another?

New research is turning conventional wisdom on its head, revealing that the way your body responds to carbohydrates isn’t as simple as we once thought.

Scientists have built a national glycemic index (GI) and glycemic load (GL) database to help us make better dietary choices, but there’s a catch—our bodies don’t always follow the numbers. Here’s what you need to know…

Key Takeaway

• Two people can eat the exact same food and experience utterly different blood sugar spikes, proving that GI values aren’t universal.
• Diets high in high-GI foods (like white bread and soda) are strongly linked to diabetes, heart disease, and obesity.
• Even though personalized nutrition is the future, experts agree that sticking to whole grains, legumes, fruits, and non-starchy vegetables is a reliable way to support metabolic health.

Glycemic Index vs. Personalized Nutrition: The Future of Blood Sugar Control

Health experts have created the first national glycemic index and glycemic load database. This reveals how foods containing carbohydrates affect blood sugar levels. This is important to know because high blood sugar substantially increases the risk of developing heart disease, diabetes, and dementia.

The team that created it hopes their work will help people make more informed food choices. But there’s a catch… Two people can eat the same amount of the same food, yet their blood sugar responses can be completely different.

Using The Glycemic Index

The Glycemic Index (GI) is a scale that categorizes the quality of carbohydrates according to their impact on blood sugar. High-GI foods like white flour and sugary cereals cause a “sugar rush” that can negatively impact metabolic health. The glycemic load (GL) factors in the GI value and the serving size.

A team of researchers at Brigham Young University (BYU) in Utah led by Karen Della Corte, professor of nutrition and dietetics, developed the database to offer insights into the evolving quality of carbs consumed in the United States.

Soft Drinks And White Bread Are The Worst Offenders

“Large-scale studies have shown that both high GI and GL diets are associated with an increased risk of Type-2 diabetes, cardiovascular disease, and some cancers,” she noted. “In addition, high-GI foods lead to quicker hunger and increased caloric intake and contribute to weight gain.”

To create the database, the team used the National Health and Nutrition Examination Survey (NHANES), which provided a sample list of nearly 10,000 foods Americans eat daily. It developed an AI-enabled model that analyzed foods based on their GI and GL. The AI matched the foods from the NHANES based on the food descriptions with their correlated GI/GL values.

Professor Della Corte said that looking forward, “many new and important questions can now be investigated using this database relating to the role GI and GL play for chronic disease risk in the U.S.”

Over the period from 1999 to 2018, they found soft drinks and white bread were top contributors to dietary GI and GL. Interestingly, over these 20 years, the GI of the 49,205 NHANES adult participants fell by 4.65 and the GL by 13.8, even though obesity rates rose by more than a third over the same period, which begs the question of how useful these indices are.

We’ll come back to this shortly.

Eat Whole Foods

Professor Della Corte wanted to emphasize the importance of eating whole foods: “One key takeaway from this study,” she believes, “is the importance of prioritizing low-glycemic carbohydrates in the diet. This means focusing on whole, minimally processed foods that release glucose slowly into the bloodstream and prevent spikes in blood sugar levels. Making swaps from refined grains to whole grains can help improve the healthfulness of the diet and lower the overall dietary GI.”

She continued that being aware of low glycemic foods allows people to make more informed choices, turning your pantry into a “GI-friendly zone.” She suggests adding the following items to your grocery list:

• Whole grains
• Beans
• Lentils
• Chickpeas
• Brown or wild rice
• Quinoa
• Barley
• Steel-cut or rolled oats
• Non-starchy vegetables
• Fruits
• Nuts

The professor’s advice is sound. Eating lower GI/GL whole foods with their higher fiber content and nutrients is far superior to high GI/GL refined, processed, sugar-laden foods. This will lower the risk of chronic disease, as found in major studies quoted in the BYU group’s paper published in The American Journal of Clinical Nutrition.

High GI Foods Linked To Chronic Disease And Early Death

A systematic review by an international research group found diets high in GI and GL were robustly linked with the incidence of type-2 diabetes.

A nutrition and chronic diseases expert group provided convincing evidence of the causal effects of GL on cardiometabolic outcomes, including coronary artery disease, stroke, and type-2 diabetes.

A recent meta-analysis assessing the highest-quality data found consumption of high GI foods was significantly linked with an increased incidence of diabetes, heart disease, diabetes-related cancer, and death from any cause.

GI and GL are valuable tools that can be relied on. But not so fast. How food affects people is far more complex than these indices suggest.

Huge GI Variation in a Single Food

The GI puts a number on a single food, but this isn’t realistic as meals contain combinations of ingredients in varying amounts. For instance, potatoes have a high GI but needn’t negatively impact blood glucose levels depending on how they are prepared and what they’re eaten with.

Professor Julie Miller Jones, a renowned expert in the field of nutrition and food science, writes that:

1. A food’s GI can vary as much as five-fold depending on the form of the food and how it’s measured.
2. Food eaten at the previous meal can affect the glycemic response at the current meal.
3. Day-to-day variation in the same subject is often more significant than the variation between subjects.

Moreover, the renowned Weizman Institute of Science in Israel found that individual blood sugar levels can vary dramatically in response to eating the same food. They found the GI to be a poor predictor of the actual response to a food item because it’s not just the relevant food, but the person eating it.

Personalized Nutrition

Professor Eran Segal, who helped carry out the research, said: “The huge differences that we found in the rise of blood sugar levels among different people who consumed identical meals partly explain why so many diets fail in so many people. Our results point to personalized eating choices being more likely to help people stay healthy than universal dietary advice.”

Professor Segal and his colleagues developed an algorithm containing factors that influence the metabolism of foods. These include age, body mass index, lifestyle choices, genes, and gut bacteria, among 137 factors. This was remarkably accurate and superior to GI/GL and other approaches.

Personalized nutrition will likely be in the future rather than a one-size-fits-all approach. While we’re waiting, stick to consuming real whole foods provided by nature, and you won’t go far wrong.

Supplements Can Help Too

If you're looking to optimize blood sugar levels and improve metabolic health, certain supplements have been scientifically shown to support insulin sensitivity, reduce glucose spikes, and promote better carbohydrate metabolism. Here are some top supplements that can complement a low-glycemic index, whole-food diet:

• For insulin resistance and blood sugar control: Berberine, Chromium, Alpha lipoic acid (ALA), Magnesium
• For reducing inflammation and improving metabolic health: Omega-3s, vitamin D3 (cholecalciferol), probiotics
• For insulin spikes related to hormonal balance: Myo-inositol, Magnesium, Cinnamon
• For post-meal glucose spikes: Cinnamon, green tea and green tea extract, Alpha lipoic acid (ALA)

Whichever supplement you choose, it should be taken before your meals for the best results.

Summary

A team of researchers at Brigham Young University (BYU) has developed the first national glycemic index and glycemic load database, offering new insights into how carbohydrates impact blood sugar. Their research confirms that high-GI and high-GL diets are linked to a greater risk of diabetes, heart disease, and weight gain. However, scientists also discovered considerable variations in how individuals respond to the same food, suggesting that personalized nutrition may be the key to better health. While GI and GL can provide general guidance, factors like gut bacteria, metabolism, and lifestyle play a major role in how each person processes carbohydrates. Until more personalized solutions are available, experts recommend focusing on whole, minimally processed foods for better blood sugar control.

Frequently Asked Questions

• What is the glycemic index (GI), and why does it matter?

The glycemic index (GI) ranks carbohydrates based on how quickly they raise blood sugar levels. High-GI foods cause rapid spikes, while low-GI foods provide a slower, more stable energy release.

• How is the glycemic load (GL) different from the glycemic index?

The glycemic load (GL) considers both the GI of a food AND the serving size, making it a more practical measure of blood sugar impact.

• Can GI and GL help prevent diabetes and heart disease?

Yes! Studies show that diets high in GI and GL increase the risk of diabetes, heart disease, and even certain cancers. Choosing lower GI foods can help regulate blood sugar and improve long-term health.

• Why do some people react differently to the same food?

Individual factors like gut bacteria, metabolism, genetics, and lifestyle all play a role in how food affects blood sugar. This is why personalized nutrition is gaining attention as a more effective dietary approach.

• What’s the best way to improve blood sugar control?

While GI and GL are helpful tools, the best approach is to focus on whole, minimally processed foods like fruits, vegetables, legumes, and whole grains. Personalized nutrition may offer even better insights in the future!