Glycemic Index and Glycemic Load and Weight Loss, Tortilla Wraps, Sulfur Dioxide in Dried Fruit

Glycemic Index and Glycemic Load and Weight Loss, Tortilla Wraps, Sulfur Dioxide in Dried Fruit

Q: What do the terms “glycemic index” and “glycemic load” mean?
Q: Will lowering my glycemic index or glycemic load help with weight loss?
Q: Are the green and orange colored tortilla wraps more nutritious than regular tortillas since they are made with vegetables?
Q: What does the additive sulfur dioxide in dried fruit do?

Karen Collins, MS, RD, CDN
American Institute for Cancer Research

Q: What do the terms “glycemic index” and “glycemic load” mean?
A: Carbohydrate that is broken down quickly by the body, raising blood sugar rapidly and leading to a quick rise in insulin, is referred to as having a high glycemic index (GI). Many factors can effect the GI of a food. In general, foods with a high GI include not only sweets, but potatoes, white rice and refined breads. Foods with a low GI are digested and absorbed more slowly. Low GI foods include whole grain breads, pasta, beans, and most fruits and vegetables. Glycemic load measures foods’ impact on blood sugar based on the GI and portion size.

Q: Will lowering my glycemic index or glycemic load help with weight loss?
A: Unfortunately, we still have no clear answer that supports or refutes this theory. Some theories suggest that if blood sugar rises less after eating, insulin will be kept at levels that promote weight control and hunger will be better controlled. (Insulin is a hormone that regulates blood sugar and promotes fat storage.) One recent year-long study compared two groups of dieters: Both diets contained equal calories but the glycemic load of one diet was high and the other low. The groups showed no difference in hunger, weight loss or body fat. Insulin levels dropped in both groups due to weight loss, regardless of carbohydrate choice. However, other studies suggest that some people – such as women or sedentary people – may be more sensitive to dietary glycemic load. For now, it seems that reducing calories and increasing physical activity are most important for weight loss. If you want to experiment with reducing the glycemic load of your diet to see if that will make weight loss easier, that’s fine. Just remember that you can reduce your glycemic load as part of a balanced diet or as part of a high-fat diet with limited healthful foods. What overall research does show is that smart eating – for health and weight loss – should be built around a plant-based diet with two-thirds or more plant foods and no more than one-third animal protein.

Q: Are the green and orange colored tortilla wraps more nutritious than regular tortillas since they are made with vegetables?
A: No. So little spinach and tomatoes are used to make “spinach” and “tomato” tortillas that the nutritional difference between a colored and conventional tortilla is negligible. Some of these specialty tortillas state they contain four to six percent of the daily value for vitamin A or C. Although little bits of added nutrition do add up, this is not enough to qualify the tortillas as a source of these nutrients. The more important differences among tortillas relate to whether they are whole grain or made of refined flour, and the amount of fat added. Add plenty of vegetables and perhaps an extra salad to accompany your wrap, rather than counting on little bits of vegetables added to tortillas only for color.

Q: What does the additive sulfur dioxide in dried fruit do?
A: Sulfur dioxide is a preservative. It stops the growth of food-spoiling microorganisms and prevents fruit from browning and changing flavor. In 1985, a scientific panel concluded that sulfur dioxide in food poses no hazard to most people. Foods commonly refer to sulfur dioxide as sulfites, which is formed from sulfur dioxide and water. Sulfites do not pose any cancer risk. The concern with their safety is for people with asthma or sulfite allergies who may have reactions, sometimes severe, to these products. To help sulfite-sensitive people avoid foods that contain this substance, foods that contain detectable levels of sulfites are legally required to state this on the label.

Reprinted with permission from the American Institute for Cancer Research www.aicr.org