'The G.I. Diet:' A Food Drill

These days, finding the right foods to help you shed pounds and stay healthy can be a tough task.

To lose weight, experts have recommended everything from complex carbohydrates and no-fat diets to no carbs and high-protein diets. Now, Rick Gallop, former president of the Heart and Stroke foundation of Ontario, Canada, recommends a healthy and simple eating program in his new book, "The G.I. Diet."

All carbohydrates aren't equal. Gallop explains on The Early Show, some carbohydrates are digested faster and raise blood sugar more quickly than others. The goal of the G.I. (Glycemic Index) program is to identify the foods that provide the longest-acting energy, and the most efficient energy source for the body.

"There are two problems with diets," he tells co-anchor Rene Syler. "First problem, people can't stay on them. They fail because they go hungry. Or secondly, it's too darn complex. People get frustrated and give it up. That's where diets fail. This book is directed very simply at those. You won't go hungry because of the G.I. Index, and secondly, I color-coded all the foods into traffic light colors."

Gallop's book lists the carbohydrates as red, yellow or green, green being the lowest on the glycemic index and the ones that are the best for the body.

Gallop says the glycemic index has been around for 22 years, but it hasn't had much publicity until recently. It is a sound, medically-based theory of food calories and how they are used as energy by the body.

He explains the green-light foods are essentially fruits and vegetables. "Things like yogurt, pasta, even potatoes - small new potatoes that are boiled as opposed to baked potatoes."

The yellow light are the foods people should eat once in a while and in moderation such as chocolate and a glass of red wine. And the red light foods are the ones people should stay away from if they want to lose weight.

Things like rice cakes and watermelon, he says, are thought be good for losing weight. "They really aren't," he says, "because they digest so quickly you're looking for the next watermelon five minutes later. Same with rice cakes or cookies or bagels. They digest so quickly through your system, you're looking for the next sugar fix two minutes later. We all talk about the Chinese meal as a classic: High G.I. food, lots of rice and noodles. The old joke is 20 minutes before you finished your first Chinese meal, you're looking for the second one because you're hungry."

Read an excerpt from "The G.I. Diet":

During the fifteen years that I was President of the Heart and Stroke Foundation of Ontario, my job was to raise funds for research into heart disease and stroke to promote healthy lifestyle choices among Canadians to reduce their risk for those diseases. The foundation, a sister organization to the American Heart Association, has developed the most comprehensive set of heat disease, stroke and healthy lifestyle resources in Canada. We now know that smoking, high blood pressure, high blood cholesterol, a sedentary lifestyle, and being overweight are all major risk factors for heart attacks and strokes. So a few years ago, when I was twenty pounds overweight, I knew I had to reduce. And with all the information and resources I had, I thought I knew how: I went out and bought a Nordic ski machine and a stationary bike, and I started working out every day. But no matter how hard I exercised, I found I could only stabilize, not lose, the weight. For the first time in my life, I realized I had to go on a diet.

Conventional nutritional wisdom at the time recommended a low-fat, high-carbohydrate diet. All I had to do was stop eating fatty foods like cheese and ice cream, and to start eating more low-fat carbohydrates like pasta, rice and vegetables right? Wrong. Though I stuck diligently to the diet, eating pasta and tomato sauce instead of steak and Caesar salad, I wasn't losing any weight at all. In frustration, I turned to the filing cabinets at the Heart and Stroke Foundation of Ontario. The foundation receives literally hundreds of diet books, products, and recipes every year, all hoping for support or endorsement. Looking through the files, I quickly ruled out food-specific diets, such as the grapefruit and banana diets, because they have no scientific basis, are risky to your health, and are impossible to sustain over the long term. I also decided to avoid high-protein diets since various studies had found them to be a real health hazard. The fact that the high-protein, low carbohydrate diet that was very popular in the 1970s is back in the headlines again as the weight-loss choice of the stars is alarming news. This diet, popularized by Dr. Robert C. Atkins, is potentially a serious long-term risk to health.

The diet is based on high intake of animal protein and saturated fat with minimal carbohydrates. It works by the body burning fat for energy instead of carbohydrates. While that sounds like a good idea in principle, the process called ketosis has the potential to create a dangerous electrolyte imbalance and an acid buildup in the blood that can cause kidney damage, kidney stones, and osteoporosis by leaching the calcium from bones. Side effects include fatigue, headache, nausea, faintness, and bad breath. In addition, the high levels of red meat and saturated fat in this diet increase the risk of heart disease, stroke and some cancers...So, diets based on single food and high protein-diets were out. I was still left with a whole host of diets to try, and I selected on e that appeared to be based on sound nutritional principles. After several unsuccessful months with that one, I embarked on another, and then a few months later, another. I don't know how many of them I tried. I counted calories. I studied labels, a real challenge trying to make sense of servings, fat grams and daily percentages. I starved. I hallucinated about food. Sometimes I did lose a few pounds, but then I'd hit the inevitable plateau, unable to go any further. And since I was constantly hungry, I'd soon start eating what I wanted and gain back the few pounds I'd managed to lose.

It seemed as if I was destined to spend the rest of my life overweight. It was the most discouraging thing I have ever experienced. I couldn't understand why losing weight was so difficult, and I felt there had to be a way to slim down and maintain a healthy weight without having to feel hungry every moment of the day, jeopardizing my health, or requiring a Ph.D. in math to calculate various formulas and ratios. I was determined to find a diet that would work not only for myself, but also for others in the same boat.

My quest eventually led me to one of the nutritional researchers supported by the Heart and Stroke Foundation of Ontario. He introduced me to the G.I. or Glycemic Index ... The Glycemic Index was invented by Dr. David Jenkins, a professor of nutrition at the University of Toronto. Since he was living in my hometown, I decided to pay him a visit.

Excerpted from "The G.I. Diet." Copyright © 2004 by Rick Gallop. All rights reserved. Used by permission.