GLYCEMIC INDEX

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.

The glycemic index, is a scientific method for calculating the way carbohydrates in food act in the body. By giving foods a glycemic number, ranging from 0 to 100, you know at a glance what to expect. Because people rarely eat just one food by itself, and because folks tend to eat varying amounts of foods, scientists also came up with the glycemic load. It takes into account all the carbohydrates in foods you eat at one time, along with the amounts of those carbohydrate-containing foods, and calculates a number. In short, the glycemic index and glycemic load are all about choosing carbohydrate-containing foods wisely and putting them to work for you.

A Brief History of the Glycemic Index

In 1981, scientists at the University of Toronto conducted ground-breaking research on the blood sugar effects of 62 different types of foods containing carbohydrates: vegetables, fruit, milk, legumes, and breakfast cereals. They found significant differences between different types of carbohydrate-containing foods, which led them to suggest using the glycemic index as a way to classify carbohydrate foods by how quickly they raise blood sugar levels. The glycemic index was first used as a way of helping people with diabetes control their blood sugar levels, moving beyond simple carbohydrate counting. Over the years and with more research, the glycemic index has become an important nutrition tool for several other chronic conditions, including Polycystic Ovary Syndrome (PCOS), metabolic syndrome, and diabetes.
Jennie Brand Miller, of the University of Sydney’s Human Nutrition Unit, is one of the recognized leaders in glycemic index research. She’s the lead author of the authoritative International Tables of Glycemic Index published by the American Journal of Clinical Nutrition. Her group continues to test the glycemic index of a wide variety of different foods so that consumers, health professionals, and scientists can know exactly how different foods influence blood sugar.
Australia and Canada continue to be leaders in testing large numbers of foods to help consumers more easily choose low-glycemic foods. Australia started the GI Symbol Program in 2002 to clearly identify proven low-glycemic foods. Canada, Australia, and the United Kingdom have approved the GI Symbol for use on food labels, making it easy to find low-glycemic foods in these countries. The United States has adopted a seal from an accredited testing organization; food companies can have their foods tested by the organization and can use the Low Glycemic Seal if their foods pass the test.

Ten Low-Glycemic Foods with Great Health Benefits.

Lowfat Yogurt

Yogurt is a fermented dairy product made by adding bacteria cultures to milk, resulting in a thicker texture and a tart, tangy taste. A wide range of bacteria is used to make yogurt, and each different bacteria strain has specific potential health benefits. The good news is that all the types of live bacteria found in yogurt help promote overall health. Unfortunately, not all yogurt sold contains live active cultures.
For the purpose of shelf-stability, many yogurts are heat treated — a process that kills off the healthy bacteria. So as you’re choosing yogurt, select containers that say live active cultures somewhere on the label. Also be sure to pick lowfat varieties to avoid unnecessary fat and calories. Yogurt is a good source of calcium, riboflavin, protein, vitamin B12, potassium, and zinc. Many types of yogurt now also contain added vitamin D, which together with calcium helps build strong bones. Recent research shows that many people are deficient in vitamin D, which can lead to numerous health problems such as high blood pressure and some types of cancer. Eating yogurt with added vitamin D can help prevent you from developing a vitamin D deficiency.

Peanuts

Fun fact for the day: Peanuts aren’t actually a nut — they’re a legume! Peanuts are a good source of manganese, tryptophan, niacin, and folate. The fat in peanuts is the healthier monounsaturated fat that helps protect against heart disease. Peanuts are also a good vegetarian source of protein. Unlike animal sources of protein, peanuts contain fiber, specifically 9 percent of your daily fiber needs in a 1-ounce serving.

Artichokes

The artichoke is a much-loved vegetable that’s a star of the Mediterranean diet, a traditional, heart-healthy way of eating found in countries surrounding the Mediterranean Ocean. Artichokes contain a high amount of antioxidants that provide an overall boost to your health. They’re also a good source of vitamin C. And don’t forget that one medium artichoke has more fiber than 1 cup of prunes! Often people eat artichokes by pulling off the leaves one at a time and running each leaf through their teeth to remove the soft, pulpy portion. If you’re in a hurry, choose baby artichokes, which can be eaten whole, or purchase marinated artichoke hearts.

Asparagus

It’s amazing how much nutrition is packed into each tender spear of asparagus. With only four calories per spear, asparagus is a favorite vegetable for anyone conscious of her calorie intake. Asparagus is also a good source of potassium, fiber, folate, thiamin, and vitamin B6, plus antioxidants (such as glutathione) that help protect against cell damage that may lead to cancer.

Broccoli

Broccoli routinely makes the list of “super vegetables” that contain extremely high amounts of nutrients. It’s a cruciferous vegetable that contains anticancer compounds and phytochemicals that may help protect against heart disease. One cup of steamed broccoli contains more than 200 percent of your daily intake of vitamin C; it’s also a good source of vitamin K, vitamin A, folate, and potassium.

Cauliflower

Some people think that white vegetables have little nutritional value, but cauliflower is actually a nutrition powerhouse. A cruciferous vegetable, cauliflower contains compounds that protect against cancer, plus high amounts of vitamin C, folate, and fiber.

Lettuce

Hundreds of different types of lettuce are available today, and all of them are very low in calories and have high water content, which helps fill you up so you feel satisfied longer. Varieties of lettuce with darker-green leaves contain higher amounts of vitamins and minerals compared to the lighter-colored types of lettuce. For example, romaine lettuce is an excellent source of vitamin K, vitamin A, vitamin C, folate, and manganese. Yet don’t pass up lighter green lettuces such as iceberg or butterhead completely; they also contain antioxidants and healthy amounts of several vitamins.

Peppers

All colors of peppers are good sources of vitamins A and C. Red bell peppers (which are actually fully ripened green peppers with a milder flavor) contain lycopene, a phytochemical that may help reduce the risk of some types of cancer. Choose a variety of colors of peppers for their taste, visual appeal, and nutrition content.

Spinach

Popeye was right — spinach is a good vegetable source of iron. It also contains antioxidants that help protect against cancer, as well as vitamins C and A to help promote a healthy heart and cardiovascular system. Toss raw baby spinach into salads or add it to your favorite rice at the last minute of cooking for a splash of color and flavor.

Tomatoes

For a vegetable once believed to be poisonous, tomatoes have come a long way nutritionally. They’re a rich source of lycopene, especially when cooked. Tomatoes are also a good source of vitamin C, vitamin K, and folate.

Excerpts from the book "The Clycemic Index Diet for Dummies" by Meri Raffetto RD, LDN, founder Real Living Nutrition Services, Wiley Publishing, U.S.A, 2010. Compiled, adapted and illustrated to be posted by Leopoldo Costa

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