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What’s so complex about carbohydrates?
Carbs and body weight

What’s the ‘glycemic index’?
What’s the ‘glycemic index’?

If you keep up with the latest fad diets, you’ve probably come across the term “glycemic index” at least once. You may even be wondering if you should refer to it when making food choices. The answer, in a nutshell, is no.

The index tracks how quickly food is converted into blood sugar—the faster the rate, the higher its ranking on the index. It also considers factors such as fiber, fat and refined sugar content, and if the food was served cooked or raw.

Some researchers believe that the quicker carbs are absorbed as glucose into the bloodstream, the greater the risk of developing diabetes. Many nutritionists, however, consider the index junk science—certainly, not a practical guide to a healthy diet. A primary flaw: It ranks each food by itself without considering its value as part of a meal. As a result, some very nutritious foods, such as raisins and carrots, are high on the index.

Carbohydrates are nothing more than molecules consisting of carbon and water, present in a vast array of the foods we buy—from fruits, vegetables and breads to milk, soda and pancake syrup. Carbs are basic to good health, giving us the vitamin, mineral and antioxidant fuel our bodies need to think, grow, maintain cellular functions, even fend off illness.

Yet these rather ordinary compounds remain the subject of continual debate by health experts and weight-conscious consumers. For some time, diet gurus have been targeting carbohydrates as a weight-gain culprit. The Atkins diet, the Zone diet and Protein Power are examples of popular plans that advocate cutting back on bread, rice, pasta, cereal and fruits and eating mainly meat, fish, eggs, nuts and dairy products. The result: a mixed bag in which proteins—and all too often, fat—take center stage. Eliminated along with the carbohydrates are the essential vitamins, minerals and phytochemicals they provide—nutrients that help protect our bodies from heart disease and cancer. Those who stick with high-protein, low-carbohydrate plans long enough tend to lose weight—and muscle mass. That’s because when carbs are banished from the diet, the body turns to valuable muscle for fuel. Give the diet more time and the metabolism slows—along with the weight loss. Before you can say, “Let’s have steak for dinner again!” the pounds start creeping back on.

Carbs and body weight

Carbohydrates are largely plant-based foods that become sugar in our bodies during digestion. Simple carbohydrates are usually sweet; examples include table sugar, honey, candy, fruit, milk and juice. Complex carbs include starchy and fibrous foods such as potatoes, rice, bread, whole-grain foods, vegetables and legumes. It takes the body several steps to break down complex carbohydrates before they can be absorbed as sugar into the bloodstream.

Carbohydrates should account for about 55 percent to 60 percent of a healthy diet. Of course, not all carbohydrates are created equal—and that’s something to keep in mind when planning your daily food intake. Follow these tips to make carbs a valuable part of your healthy diet—and one that won’t sabotage your weight-management efforts:

  • Choose wisely. Aim for complex carbohydrates with a high fiber content, such as whole grains, legumes and vegetables while limiting low-fiber carbs such as white bread, bagels and refined pasta. Complex carbs are digested more slowly than simple carbohydrates, keeping blood sugar levels even. What’s more, they appear to offer protection against heart disease, high blood pressure and some forms of cancer.
  • Reduce sugary snacks. Cut back on processed, sugary foods like cookies, cakes and candy. The sugar in simple carbs is absorbed directly into the bloodstream, causing blood sugar levels to soar. In addition, these foods tend to be high in fat—fill up on them regularly and you’ll make yourself vulnerable to obesity, diabetes and other conditions.
  • Watch portions. Added pounds show up when we consume too much of any food, not just carbohydrates.

To keep your carbohydrate intake in check, it will help to know that a serving equals:

  • 1/2 cup of cereal, rice or pasta
  • one slice of bread
  • 1/2 bagel
  • 6 saltines
  • 1 cup of raw, leafy green vegetables
  • 1 medium potato
  • 3/4 cup of fruit or vegetable juice
  • 1 medium orange

In addition, the USDA Food Guide Pyramid recommends six to 11 servings from the bread, cereal, rice and pasta group; two to four servings from the fruit group; and three to five from the vegetable group.