BioEd Online

Teacher Background

Personal choices are part of everyday life. Whether choosing what to wear in the morning, what to have for lunch, or which college to attend, our days are filled with decisions. Do we approach decision-making in a systematic and organized way? Perhaps not often enough, particularly when making decisions that affect our health, or that of our family members. A 2009 study concluded that more than one million people die needlessly each year due to decisions they have made. Why do we make poor choices, such as smoking, eating lots of high-sugar foods, or drinking too much alcohol? Peer pressure, resistance to change and misperceptions about risk all contribute to choices with potentially bad outcomes.

A choice that involves risk implies possible negative consequences. While we cannot avoid all risk (the Chinese symbol for risk even combines two characters, corresponding to “danger” and “opportunity”), solid decision-making requires the ability to assess risk and apply evidence appropriately. Consider the possible outcomes of a driver speeding to work or school in the morning. If all goes as planned, the motorist arrives on time to begin his or her day. But other more negative outcomes, such as being ticketed for speeding or having an accident, also are possible. Behavior that involves risk always can have a negative outcome. Fortunately, we can learn to make better choices, particularly those related to our health.

This lesson poses a simple choice: should students drink a sugar-sweetened beverage, or not? Studies show that people who regularly eat or drink products with added sugar tend to consume more calories than people who consume fewer of these items. Research also links sweetened beverages to weight gain. Cutting back on added sugars, especially from sweetened beverages such as regular soda and fruit-flavored drinks, can help to maintain a healthy weight and reduce the risks for several diseases.¹

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¹ National Heart, Lung and Blood Institute (www.nhlbi.nih.gov).

Objectives and Standards

Materials and Setup

Teacher Materials (See Setup)

• Pad of sticky notes (one note per student)

• 16- or 20-oz bottle of soft drink, any flavor (not sugar-free or diet)

Materials per Group of Students

• Plastic teaspoon

• 16-oz clear plastic cup

• 30 single-serving sugar packets

• Empty soft drink can or single-serving bottle (not sugar-free or diet, groups may have bottles from different sizes and kinds of drinks)

• Access to a calculator or computer

• Sheet of 8.5 in. x 11 in. paper

• Tape or glue stick

• Copy of “Sweetened Soft Drinks” page (one per group or student)

• Copy of “Selected Causes of Death” page (to save time in class, you may cut the sheet into strips for students ahead of time)

• Pair of scissors (only if students will be cutting statements into strips)

• Copy of “Lifetime Risk of Dying from Different Causes” page

Setup

1. Place all supplies in a central location for distribution and return.

2. Students should work in groups of four.

Procedure and Extensions

Part One: Informed Choices

1. Tell students they will explore human body systems and learn how to use evidence to make better decisions for themselves, or maybe other people. They will place themselves in the roles of scientists, healthcare providers and even persons with common health problems. Ask, Would you choose to have diabetes? How about cancer or heart disease? Follow by asking, Do we deliberately choose or decide on bad things for our lives? Allow a few minutes for students to think about and discuss these questions.

2. Follow by saying, Let’s focus on a simple decision. Show students a standard 16- or 20-ounce soft drink bottle. Ask for a show of hands in response to the question, Would you decide to drink this beverage? Create a T-chart on the board with one side labeled “yes” and the other side labeled “no.” Give every student a sticky note and have each write one reason either for (“yes”) or against (“no”) consuming the soft drink. Have a few students collect and post the notes on the chart. Tally the notes “for” and “against,” and announce whether or not the majority of students would drink the bottle of soda.

3. As a class, identify and discuss the most common reasons for or against consuming the soft drink. Ask, Do any of these reasons change your thinking?

4. Tell students that they are going to gather more information about the soft drink. Divide the class into teams of four students, and have each team pick up the following supplies: one clear plastic cup, 30 sugar packets, one empty soft drink container, and at least one copy of the “Sweetened Soft Drinks” page.

5. Have each team follow the instructions on the “Sweetened Soft Drinks” page, and estimate the number of teaspoons of sugar in a 16- or 20-ounce soft drink (same size as shown to the class earlier). Tell them to be realistic, and explain that each sugar packet contains approximately one teaspoon of sugar. Direct teams to count out (but not open) the number of sugar packets they predict for the soft drink, and place the packets in their plastic cups.

6. Have teams compare the amounts of sugar estimated by the different groups.

7. On the board, write the grams of sugar in the drink you brought to class (a 16-ounce bottle typically has 54 grams of sugar; a 20-ounce bottle has 65 grams). Have each team use the formula below to calculate the number of teaspoons of sugar in the soft drink.
   
   Number of teaspoons of sugar = total grams / four grams of sugar per teaspoon

8. Have teams report and discuss their calculations. A 16-ounce drink with 54 grams of sugar would have 13.5 teaspoons of sugar; a 20-ounce drink with 65 grams of sugar would have 16.25 teaspoons.

9. Ask, How many Calories do you think are in the soft drink? Direct teams to complete the sheet and report their results to the rest of the class.

10. Have students put the sugar packets back into the cup and return all supplies to the central station.

11.  Ask students if they were surprised by the amount of sugar or Calories in the soft drink. Discuss the role of carbohydrates in living organisms. Carbohydrates store energy in the form of chemical bonds. This energy becomes available when our bodies process the food we eat. When we eat too many Calories, the excess energy can be stored as fat.

12. Ask, Given what you now know about the sugar content in this soft drink, would you choose to consume it? Have students raise their hands or move their sticky notes to the appropriate side on the T-chart. Ask, Have you ever had a “Big Gulp”? Did you know that a 32-ounce soft drink has about 27 teaspoons of sugar and 432 Calories?

13. Ask, Might you make different decisions about soft drinks in the future, based on what you just learned? Why or why not? Lead a class discussion about the importance of using accurate information to make decisions. Mention that most decisions require us to choose between multiple options, which can lead to different outcomes (positive or negative).

Part Two: Risk

1. Ask, Do you think some decisions are riskier than others? What is “risk,” anyway? [Risk involves behaviors or actions that have possible adverse outcomes.] Explain that one way to quantify risk is to state it as likelihood that something will occur. In fact, scientists are able to estimate the risk of many kinds of events by studying how frequently they have happened in the past.

2. Provide a “Selected Causes of Death” sheet to each student team. Teams should read all of the statements, and use the scissors to cut the statements into strips (unless you have pre-cut the sheets).

3. Have teams discuss and predict how likely it is for each event to occur, and then arrange the statements from highest risk (top) to lowest risk (bottom). Provide tape and a separate sheet of paper on which students can secure their strips.

4. Discuss students’ predictions briefly, asking which causes of death they ranked as being the highest and lowest risks. Allow groups to share some of their predictions and explain the reasoning behind their choices.

5. Distribute a copy of the “Lifetime Risk of Dying from Different Causes,” sheet to each group, or project the sheet in front of the class. Tell students that the sheet shows estimates of the lifetime risk of dying from a variety of causes, based on the United States population. (In this activity, “lifetime risk” is the likelihood that an average person will die from the disease or type of accident indicated.)²

6. Lead a class discussion in which students compare their predictions to the actual statistics. Students will discover that two leading causes of death in the United States (heart disease and stroke) involve the cardiovascular system.

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² National Safety Council. 2012. Lifetime odds of death for selected causes, in Injury Facts 2012 Edition, pages 41–43.

Extensions or Homework

• Have each student record (1) the kind and size of each sweetened drink (soft drinks, sweet tea, juice drinks, etc.) that he or she consumes in a 24-hour period, and (2) use label information or online calorie counters to estimate the total amount of sugar and calories in those drinks.

• The FDA recently began taking steps to reduce or eliminate the use of artificial trans fats in foods, because they increase the risk for heart disease. Lead a class discussion, or have students write essays about the pros and cons of taking similar action to limit the amount of sugar that manufacturers add to foods.

Handouts and Downloads