11.6 Consider This: Another Food Pyramid

The Mediterranean diet is favored by some health professionals in preference to the USDA Food Pyramid. The diet is prevalent in countries bordering the Mediterranean Sea, especially those along the eastern and southern shores.

1. Use a search engine to find out the details of such a diet and compare it with the Food Pyramid.
2. What are the major differences in the diets?
3. Find out why the Mediterranean diet is favored by some health professionals.

11. 9 Consider This: Lactose Intolerance - A Closer Look

Here are three questions on which to try your chemical detective skills using the Web by searching for "lactose intolerance." Reading the labels in your cupboard or at a nearby store can also help you milk out some information.

1. Over-the-counter digestive aids allow you to increase your intake of dairy products. How do these work? What are their advantages and disadvantages?
2. Even with digestive aids, you may risk not getting enough calcium, an essential mineral that you will learn more about in Section
3. Sometimes lactose turns up in foods in which you least expect it, such as bread. Although lactose may not be listed on the label, you will see ingredients such as whey, milk products, nonfat dry milk, or dry milk solids - all of which contain lactose. Find three other non-dairy foods that you may have to watch out for if you are lactose intolerant.

11.11 Consider This: Are Unsaturated Fatty Acids Better for You Than Saturated Ones?

Unsaturated fatty acids can be either in a cis or trans orientation. There is controversy about the role of trans fatty acids in the diet. Use the Web to answer these questions. Write a news article about your findings.

1. What is the structural difference between cis and trans fatty acids?
2. What is the controversy regarding dietary trans fatty acids?
3. Have studies been completed that resolve the controversy? If so, cite them.

11.13 Consider This: Cholesterol Content of Various Foods

The text mentions that an egg yolk contains significant amounts of cholesterol, whereas foods that are not derived directly from animals such as fruits and vegetables have no cholesterol. Use the Web to find the cholesterol content of various foods. List two foods that are high in cholesterol and two foods (not fruits or vegetables) that have much lower cholesterol levels.

11.15 Consider This: Current AHA Recommendations

Have the American Heart Association's recommended values for cholesterol, HDL, and LDL changed from those reported in this section? Check the current recommendations at the AHA . If there are any differences, explain why.

11.16 Sceptical Chymist: Olean, A "Fake" Fat

Americans eat about 22 pounds of salty snack foods per capita every year. Olean, a nonfattening, non-metabolizable fat developed by the Procter & Gamble Company, was approved by the FDA in 1996 for use in salty snack foods such as potato chips and tortilla chips. In spite of having FDA approval, Olean remains controversial, with supporters and detractors. Use the Web to locate the Olean web site as well as other sites that present contrasting viewpoints.

1. How does Olean work? Why is it not digested?
2. What are the drawbacks to using Olean in snack foods?
3. Why is the use of Olean in this way controversial?
4. Present accounts expressing opposing viewpoints regarding the use of Olean.
5. What is your decision about using products containing Olean? Explain your reasoning.

Hint: Sites that highlight the controversies may be difficult to locate. Try switching to other search engines if your first search isn't fruitful. Here are two starting points, one from the American Heart Association and the other from the Center for Science in the Public Interest. Also check this site for teachers that has a case study about Olestra.

11.19 Consider This: 3-D Amino Acids

Structural features of amino acids are more readily apparent if you look at their three-dimensional representations. Here are the molecular structures for several amino acids: glycine , alanine , phenylalanine , leucine , cysteine , aspartic acid , and the entire set. To view the molecules, you will need to install a "plug in" called CHIME .

1. How is the three-dimensional structure of glycine different from the two-dimensional structure shown in your text?
2. Glycine is the simplest amino acid. It contains only two functional groups ( - NH2 and - COOH) and only the elements C, H, O, and N. Browse through the CHIME collection of amino acids and then describe two ways in which their structures are more complex than glycine's.
3. In leucine, what four different groups are bonded to a central carbon atom? Is this molecule optically active? Explain your answer.

11.20 Consider This: Vegetarian Complementarity

Use the Web to find at least two additional examples of complementarity.

1. What essential amino acids are involved in the combination?
2. Do these combinations involve common foods of that country (such as peanut butter and bread in the U.S.)?

11.21 Consider This: Searching for Sweetness

Aspartame received FDA approval in 1981, but the search for artificial sweeteners has continued. Use the Web to find out if any artificial sweeteners have received FDA approval since 1981.

1. Identify the artificial sweetener(s) and its (their) intended uses.
2. Describe the chemical composition of the sweetener.

11.28 Consider This: Megadosing Vitamin C

In the past, there have been claims that megadoses of vitamin C prevent the common cold and may be effective against certain types of cancers. Use the Web to determine whether other evidence to the contrary has been discovery about the efficacy of megadoses of vitamin C.

1. What dose of vitamin C constitutes a megadose?
2. Where was the research conducted?
3. What were the results of the research?

11.29 Consider This: Getting Well Using Radioactive Iodine

Hyperthyroid individuals suffer from an overactive thyroid and accelerated metabolism. Use the Web to find out how radioactive iodine-131 is used to treat hyperthyroidism.

1. What role does I-131 play in the treatment?
2. Isn't radioactivity bad for the patient? Explain.
3. What further treatment does the patient need after the I-131 is used?

11.30 Consider This: Food Irradiation...Thanks or No Thanks?

Food irradiation remains controversial. The Food Irradiation Information web site suggested that the Web provides "a unique opportunity to communicate the facts about food irradiation to journalists, educators, food company executives and the general public." Indeed, the Web can link a host of constituents with differing viewpoints on a topic such as food irradiation. Use the Web to prepare a position paper on whether food should be irradiated. The paper can be written from the standpoint of a food company executive, a manufacturer of irradiation equipment, a government official, or a consumer activist. Be sure to cite your sources. Later, you may wish to join with others to stage a class debate about the issues involved.