The Glycemic Index Diet for Dummies (4 page)

This information is good to know, but it goes beyond what's essential for your basic understanding of the glycemic index. If you're the type of person who likes to know more, you'll enjoy these tidbits. If not, feel free to skip 'em.

When you see this icon, you're sure to find handy bits of information that'll inspire you and make your transition to a low-glycemic lifestyle a little easier.

Pay close attention to the information next to this icon. It'll help you avoid common pitfalls that can hinder your weight-loss efforts.

Where to Go from Here

If you like to read the last couple pages of a novel first to see whether you're going to like it, go right ahead with this book. That's right, my friend. You don't have to start with Chapter 1 and read straight through to the end. Peruse the Table of Contents, pick out the topics that mean the most to you, and start there. Feel free to flip back and forth and read what you need at that moment.

If you're a newbie when it comes to the glycemic index, start with Chapters 1 and 2. If you're already somewhat familiar with the glycemic index but aren't sure about the glycemic load, go to Chapter 4. Ready to begin incorporating low-glycemic foods into your diet? Check out Part II for advice and Part IV for some delicious recipes. Wherever you decide to start, you're sure to pick up useful, empowering information that you can continue turning to for years to come.

Part I

In this part . . .

The glycemic index was originally developed as a way to scientifically determine how different foods that contain carbohydrates — fruits, vegetables, grains, legumes, and dairy products — affect blood sugar levels. Since that initial research took place more than 30 years ago, scientists have come to understand that the glycemic index can be effectively used in a variety of ways, including weight loss.

This part explains the glycemic index and introduces you to the glycemic load, one step beyond the glycemic index that incorporates the amounts of foods you eat. In these pages, I review the role of fiber in your food choices and show you how using the glycemic index can helyou feel more satisfied while consuming fewer total calories. After you understand how the glycemic index works and its role in promoting healthy weight loss without the need to follow a specific or restrictive diet, I help you figure out how using the glycemic index can work for your individual situation.

Chapter 1
:
Introducing the Glycemic Index and How to Use It to Lose Weight

In This Chapter

Surveying the ins and outs of the glycemic index

Looking at how using the glycemic index can help you lose weight

Recognizing that the glycemic index "diet" isn't like diets you've tried before

Reviewing the additional benefits of following a low-glycemic diet

T
he glycemic index was first introduced in the early 1980s as a way for people with diabetes to achieve tighter blood sugar control and improve their overall health. Only 62 foods were part of the original glycemic index research. Fast forward to today, and you find that hundreds of foods have now been tested. Companies are even working to develop lower-glycemic foods to meet growing consumer demand.

In this chapter, I review the research behind the glycemic index and explain how adding more low-glycemic foods to your diet can help you lose weight, embrace a healthier lifestyle, decrease your risk of heart disease, manage your blood sugar, increase your energy levels, and improve your mood. Sure, all of that may sound too good to be true, but the scientific research is clear: Looking beyond total carbohydrate content of foods into how different foods affect blood sugar and insulin levels opens up a doorway into good health.

Getting to Know the Glycemic Index

The
glycemic index
is a scientific way of looking at how the carbohydrates in foods affect
blood
glucose,
or blood sugar, levels. Scientists know that all carbohydrates raise blood sugar, but the glycemic index takes this understanding one step further by figuring out how much a specific food raises blood sugar.

When you use the glycemic index to plan your meals and snacks, you're following a glycemic index diet. It's not a "diet" in the sense that there are specific meal plans you need to follow, lists of foods to eat and foods to avoid, and other types of rules that are all too familiar to people who've tried various weight-loss diet plans. Instead, the glycemic index gives you a method for selecting foods that meet your specific needs and desires.

You know those oerlay maps, where you start with a very basic map, add an overlay with more detail, then add another overlay with yet more detail, and so on until you have a complete picture of a specific area? Think of using the glycemic index in a similar way.

The first "overlay" is basic meal planning. Your body tells you it's hungry and wants food.

Next comes the layer of basic nutrition, which is all about balance. Your meal needs to include protein (chicken, fish, lean red meat, soy products, eggs, nuts/seeds), vegetables, and starch (potato, pasta, rice, bread) to keep your body happy. If you throw in a glass of milk and some fruit on the side, your body will be even happier.

Finally, you add in the glycemic index for a complete picture. Because the glycemic index applies solely to foods that contain carbohydrates, it applies only to the vegetable, starch, milk, and fruit portions of your meal. Theoretically you already have an understanding of these foods' nutritional values. The glycemic index completes the picture by telling you how these foods will impact your blood sugar, which affects everything from your energy level to your food cravings.

Now that you have a basic understanding of the glycemic index, check out the following sections for the scoop on how it's measured and how an added bit of information makes it even more valuable.

Measuring the glycemic index

The glycemic index ranks foods on a scale of 0 to 100 based on how quickly they raise blood sugar levels. Foods that raise blood sugar quickly have a higher number, whereas foods that take longer to affect blood sugar levels have a lower number.

To measure the glycemic index of a food, a specific weight of the digestible carbohydrates in the food (usually 50 grams, which is about 4 tablespoons of sugar) is fed to at least ten different people who volunteer for the study. Their blood sugar levels are measured every 15 to 30 minutes over a two-hour period to develop a blood sugar response curve. The blood sugar response of each food is compared to that of a test food, typically table sugar (glucose), which is assigned the number 100. The responses for each test subject are averaged, resulting in the glycemic index number for that food. Every individual person may have a slightly different glycemic (blood sugar) response to foods, which is why the tests use a number of volunteers and average their results together.

The information on glycemic index (GI) lists is divided into three basic categories so you don't have to get caught up in numbers and can instead focus on the primary goal of the glycemic index — choosing foods that keep your blood sugar levels more even, resulting in longer-lasting
satiety
(the feeling of fullness) and improved health. Here are the three categories: