Current Topics in Food Safety & Nutrition IFIC Foundation http://ific.org September / October 2006 Shopping for Health? Check Out these Food Components ore and more consumers The Produce Department— and many different flavonoids in Mare aware of the relationship A Cornucopia of Healthful berries, cherries, grapes, cranberries, between diet and health and are apples, onions, and more. The interested in learning more about Components tongue-twisting antioxidants, lutein foods that can promote health. With Fruits and vegetables are and zeaxanthin, may contribute to this is mind, it is important that especially praised for being chock- maintenance of healthy vision. Look consumers understand how to put full of an array of plant components for them in kale, collard greens, nutrition information into practice. that contribute to good health spinach, corn, and citrus fruits. Where better to practice nutrition including vitamins, minerals, fiber knowledge than the grocery store! and phytonutrients, not to mention Even the most saavy shoppers their high levels of antioxidants, can discover something new when which defend against damaging free it comes to shopping for foods radicals that occur in the body. Free that promote health. Nutrition radicals are linked to diseases such communicators can assist shoppers as cancer, cardiovascular disease, by applying the latest nutrition cognitive impairment, Alzheimer’s science to everyday tasks, such as disease, immune dysfunction, grocery shopping. cataracts and macular degeneration. Fortunately, there are tools all Some common antioxidants over the grocery store to direct in fruits and vegetables are consumers to make healthful food beta-carotene (which the body choices. In-store nutrition staff also converts to vitamin A) in and pamphlets are two resources carrots, pumpkin, sweet potato consumers can be directed to. They and cantaloupe; vitamin C in can also consult food packages strawberries, guava, sweet red for Food and Drug Administration or green pepper, kiwi, and citrus regulated nutrition information fruits such as oranges, grapefruit, including the Nutrition Facts panel, lemons, and limes; sulforaphane • Shopping tip: Eggs are also an claims about the nutrient content of and dithiolthiones in cabbage and excellent source of lutein and foods, and claims related to how that its cousins cauliflower, broccoli, zeaxanthin. food might be beneficial in reducing Brussels sprouts, kohlrabi and kale; • The antioxidant lycopene in risk of disease or promoting health. sulfides in garlic, onions, and leeks, tomatoes, watermelon, papaya, and red or pink grapefruit may Carbohydrate Confusion: help keep the prostate healthy and may also contribute to heart What You Need to Know about the Glycemic Index ........................2 health. Nutrition and Food Safety Myths and Facts .........................................4 (continued on page 6) INSIDENewsBites ............................................................................................7 that it raises blood sugar levels by less Carbohydrate than half (41 percent) of what an equal amount of glucose does. Confusion: What Is Glycemic Load? Glycemic load (GL) is a related What You Need to Know concept that considers both the glycemic index and the amount of about the Glycemic Index carbohydrate in a typical serving of food, giving a somewhat more accurate picture of a food’s effect on blood sugar. For example, carrots arbohydrates are an important What is the Glycemic Index? have a relatively high glycemic nutrient and a significant index because the carbohydrates C Almost all carbohydrates (sugars part of a balanced diet. Experts in carrots are mostly sugars. But and starches), regardless of the form generally encourage people to build a serving of carrots contains a low in which they are consumed, are their diets around nutrient-dense amount of carbohydrate compared digested to glucose which enters the carbohydrates, incorporating a to high GI foods such as bread and bloodstream, causing a temporary moderate amount of protein and potatoes. To calculate glycemic rise in blood glucose levels. This some fat. Exercise and weight load, you multiply the grams of glycemic response is influenced control are key elements of a carbohydrate in a serving of food by by many factors, including how healthful lifestyle to help reduce risk that food’s glycemic index. Carrots, much food is eaten, the amount and for heart disease, diabetes, and high which have a glycemic index of 71, type of carbohydrate in the food, blood pressure. have 8 grams of carbohydrates per how the food is processed, or how About 20 years ago a group of serving and are assigned a glycemic it is prepared. Under laboratory researchers developed the glycemic load of 6 (8 x 0.71). conditions, glycemic index (GI) index as a tool to measure how much is assessed by having a group of a carbohydrate-containing food is people eat a specific amount of a It’s Not That Simple likely to raise blood sugar. Since that single food (usually 50 grams of time “glycemic index” has become On the surface GI and GL sound digestible carbohydrate, i.e., total a popular nutritional catchphrase like straightforward concepts for carbohydrate minus fiber) and then and the basis for some popular enabling meal and diet planning, measuring the change in blood sugar “magic bullet” diets that advocate but experts say it’s not that simple. levels compared with the levels strict limitations on carbohydrate Here’s why. achieved after they have eaten a intake. The National Academies’ The GI value of a food varies control food (either glucose or white Dietary Reference Intake for Energy, depending on how ripe it is, its bread) containing the same amount Carbohydrates, and Fiber states, variety and how it is cooked and of digestible carbohydrate. The “Research is needed to determine the processed. Also, GI is determined International Table of Glycemic Index effect of low glycemic index foods using standard test portions of foods, and Load lists the values of both and low glycemic load diets on serum which are not the usual portion sizes control foods. The average change in lipids and other risk factors for that people consume. blood sugar levels over a set period chronic disease and complications, of time, relative to the levels after Many variables affect GI especially in high risk groups.” Is consumption of the control food, is calculations, including the fact that it really necessary to “eat by the the food’s glycemic index. the GI of a food depends on whether numbers” to lose or maintain weight? it is eaten alone or consumed with The index assigns foods a number Here are some answers to questions another food. “In the real world, on a scale of one to 100, in comparison about the glycemic index, glycemic people eat meals and diets, not with pure glucose, which has a load, and their relationship to diet single foods,” says Susan Borra, a reference score of 100. Regular pasta and health. registered dietitian and president of has a glycemic index of 41, meaning (continued on page 3) 2 Food Insight http://ific.org/foodinsight September / October 2006 (continued from page 2) Carbohydrate Confusion the International Food Information Council Foundation. A high GI ... using glycemic index or food combined with a low GI food produces a moderate response. Think of spreading some strawberry glycemic load… jam on whole wheat bread with peanut butter. The protein, fat, and it’s not that simple. fiber in the sandwich temper the relatively high GI of the jam. What about using glycemic load instead of GI? Again, it’s not that simple, since the GL calculation begins with a food’s glycemic index Think Nutrient Density investigation, these theories and thus includes all the inherent remain unproven. Also, concerns uncertainties that pertain to GI. GI and GL calculations depend on about the measurement and too many factors to enable science- GI’s rising popularity has been reliability of GI have yet to be based meal planning. However, most fueled by claims that low GI foods resolved. Glycemic index may nutrition scientists concur that a can help control appetite, weight, have the potential to be a valuable food’s nutrient density (a measure and may be useful to people with clinical tool, but it is clear that of the proportion of nutrients a diabetes. These claims are based on more research, including long- food supplies to the calories it the theory that high GI foods raise term clinical studies, is needed to contains) is more important than the blood sugar levels, cause excess prove its worth in reducing risk of glycemic index. The good news is insulin to be secreted, and lead to disease. that consumers can plan healthful the storage of fat. However, the Prevailing nutrition wisdom meals and diets without complicated American Dietetic Association (ADA) is represented by the 2005 calculations for each item on their says: “At this time, research does Report of the Dietary Guidelines dinner plates. not support the claim that a low GI Advisory Committee which states, diet causes significant weight loss or It is helpful to remember that “Current evidence suggests helps control appetite.” For people many low glycemic index foods are that the glycemic index and/or glycemic load are of little utility with diabetes, monitoring total grams naturally high in fiber. They take for providing dietary guidance for of carbohydrate continues to be the longer to digest, and may, therefore, Americans.” key strategy, ADA says, although the be more satisfying. Often they are GI concept may supplement“ blood less energy dense than their higher glucose monitoring to “fine-tune” GI counterparts. These are the food choices and modestly improve very foods—whole grains, fruits, What’s New @ blood glucose levels. vegetables, legumes—that nutrition IFIC.org? experts have always recommended A recent recommendation for Coming this fall, we’re launching and continue to emphasize as the people with diabetes from the the IFIC Foundation Publications cornerstones of a healthful diet.