Glycemic Index and Label Reading

By Melissa Majumdar, RD, LDN, CPT

A while back, I received this question from a blog follower:

"Is there a way to determine glycemic index by looking at the label?"

The answer is yes and no. The glycemic index (GI) of an item has been determined in a laboratory setting by comparing the rate of glucose, or in some cases white bread, entering the blood to sugar. Much of this research has been conducted and published through the University of Sydney in Australia. Their database is online and can be a good reference, although some of their foods will differ in ingredients and processing from American food. Assigned GIs are determined by feeding an amount of food equaling 50 grams of carbohydrates to fasting *healthy* participants and measuring the blood sugar changes over time. Unfortunately, not much research has been done showing the glycemic response within the diabetic clientel. In Australia, they even put the glycemic index rating right on the front of a product!

Many factors influence the glycemic index of a food including the fiber, protein, and fat content, manufacturing and processing practices, and other ingredients. For example, even though they are both oats, steel cut oats will have a much lower glycemic index than its highly processed cousin instant oats. Keep in mind that glycemic response differs from person to person due to genetics, hormones, activity, etc. Also, if the food is eaten in combination with other foods, the overall glycemic affect changes. Take a plain piece of bread which contains mostly carbohydrates and it will register high on the glycemic index scale (slightly lower if whole grain and less processed). Add some jelly to the toast and the glycemic affect increases; add peanut butter or turkey and the glycemic index is lower. Keep in mind that a low glycemic food does not necessarily translate to a healthy food. Despite its high sugar content, ice cream has an extremely low glycemic index because the high saturated fat content slows the absorption of sugar.

In short, the least amount of processing and more whole grains and fiber, the lower glycemic index. The more protein or fat contained within the food, the lower the glycemic index. Take home message: pay more attention to overall quality and quantity of the food than just the GI. Even a low GI food eaten in larger portions has a greater affect on blood sugars than a small portion of a high GI rated food. This principle is described as glycemic load and takes into account portion size (GL = GI x amount of carbohydrates)/100. Consider carrots - they have a relatively high glycemic index but the amount of carrots it takes to equal 50 grams of carbohydrates is about 87 baby carrots, not the traditional amount eaten!

Learn more about balancing your glycemic intake with your diet by getting a personalized Nutrition Plan from an EB Nutrition Registered Dietitian!

Inspire the Family

Pencil in 9pm on this Friday night's calendar for some family time to watch Jamie Oliver's Food Revolution on ABC. It shouldn't be too hard to convince the kids to gather round the tube - if nothing else, schedule a rain check to view the DVR or online version.

Jamie, British celebrity chef aka "the naked chef," marches into Huntington, WV, to makeover Smalltown, USA, the unhealthiest city in America according to the Center for Disease Control. Jamie's zeal for health does little to motivate and more to anger the town of Huntington. He plans to start with the kids, bond with the families, and revolutionize the way this town, and America, thinks about food. He has his work cut out for him!

Although Jamie has some wonderful principals - eat fresh (not processed) foods, nourishing the body and soul through the cooking process, and educating the youth about the origins of food - Jamie's food revolution is missing an important piece, a dietitian with the biochemical knowledge of food and the body.

Jamie comments on the USDA's (United States Department of Agriculture) school lunch regulations - he does not agree that a child needs two servings of grains per meal. He is spot on! A child's lunch will include plenty of carbohydrates from other sources besides grains - fruit (fructose) and milk (lactose) will provide plenty of energy and a well-balanced meal. But Jamie's opinions fall short of his actions when he teaches a Huntington family to cook pasta (too heavy on the oil) and shares carb-heavy recipe secrets with a teenage boy. His recipes often include a little too much sugar and butter for my liking, but his overall approach is extremely motivating a eye-opening. One more word to the wise - if you were thinking of ordering a pizza or serving chicken nuggets this evening, make sure to watch episode 2 first!

Your homework for the evening is to pour over your child's school lunch menu and decide if sending him or her with lunch money is the best idea for their longterm health. Most likely, they will fare better if you pack a piece of fruit, a serving of veggies, one grain, a 2-3 ounce serving of protein, and 1 serving of a healthy fat. Need help with school lunch ideas? Contact Melissa or Elizabeth for a Nutrition Plan and Meal Ideas for the whole family.

Curb the Cravings

Tips to Avoid Indulging
by Melissa Bosslet, RD, LN, CPT

Next time you can't say no to the Kit-Kat or you just have to have some ice cream after dinner, sit back and think about what your body is trying to tell you. Cravings - sugar, carbohydrate, salt, etc.- are signs that the body is missing something. Sometimes it is a particular nutrient, other times it is energy, and often times the body is missing the feel good hormones serotonin and/or dopamine. Serotonin is responsible for the euphoric feeling after indulging in carbohydrate rich foods. Carbs are precursors for this particular neurotransmitter, so when levels are low due to lack of sleep, insufficient sunshine, or inactivity, the brain responds by signaling your body to consume carbohydrates. Instead of picking up the donut, focus on other ways to boost serotonin levels naturally. Eat foods high in tryptophan, an amino acid that helps make serotonin, such as brown rice, chicken or turkey, yogurt, or cashews. Otherwise, catch a cat nap - 20 minutes will boost those levels, or 30 minutes of exercise will do the same thing.

Dopamine is another vital brain chemical that effects mood, appetite, and energy levels. Dopamine is easily depleted by stress, excess sugar, alcohol, or caffeine. To boost dopamine levels, focus on consuming plenty of tryptophan containing foods. Bananas, pumpkin seeds, avocado, almonds, and soy products will all help synthesize dopamine, boosting mood and shrinking that craving.

Next time a craving rears its ugly head, focus on these things:

1. Try eating a food that will lead to production of serotonin and/or dopamine
2. Avoid situations that tend to provoke cravings
3. Indulge in a nap instead of the food
   
4. Stay well nourished by eating a variety of foods every 3-4 hours to balance blood sugars and prevent serotonin lulls
5. Wait 15 minutes - often times the craving will pass
6. Really think about what the body is missing - protein? healthy fats? nutrient rich carbs?
   

Glycemic Index

Glycemic index is a quantitative way to measure how sugar affects the body. Foods are rated on how fast they enter the blood stream. They are given a "score" or glycemic index, somewhere between 1 and 100, 100 being the carbohydrates are converted to sugar almost immediately. Glucose is given a score of 100 because it is the body's ideal energy source; all sugars are converted to glucose before they are used for energy. The glycemic index is then converted to a glycemic load based on how many grams of carbohydrates the food contains. The larger the portion or the more concentrated source of carbohydrates their is, the higher the glycemic load.

food	carbohydrates	x	glycemic index	÷	100	=	glycemic load
12 oz. regular cola:	40.5	x	90	÷	100	=	36.4
fresh apple (medium)	21	x	54	÷	100	=	11.3
2 Tbsp. agave nectar	32	x	30	÷	100	=	9.6

When searching for a healthy food, consider the glycemic index or glycemic load. White or processed carbohydrates have higher indexes, and whole grains rank lower so they have less effect on blood sugar levels. Also, when carbohydrates are combined with proteins or fats, their efffect on blood sugar levels is decreased.

Glycemic Index of some commonly eaten foods.