Biology, The Science of Life

Nutrition in the Media

Overview: Students will be presented with various videos and articles about nutrition. The focus of these media is cholesterol and obesity since it is becoming an increasing problem among the youth of the Western world. This lesson has a direct link to the previous lesson on the digestive system since today’s focus is on certain consequences of the food we digest. Today's lesson will be geared towards a class discussion on science in society, more specifically, how the foods we eat affect our body. An assignment will be presented at the end of class. The goal of today's discussion is to increase awareness on the consequences various foods have on our body and media can be a solution to decreasing the population of obese individuals.

Materials: This lesson will take place in the computer lab since both the teacher and the students will need access to a computer (HP computers - Windows 7). The instructor will be controlling the students’ computers from the “head” computer (i.e. teacher’s computer) so the students are not able to use them until instructed to. The videos and articles will be displayed on their individual screens and are available lower on the page. Once the material has been covered, students will need to use Excel and the internet for the assessment component of the lesson.The videos and articles are the digital media which are used as a teaching tool.

Assessment: Students are required to make tables of a record of their daily food intakes: the amount of calories, lipids, iron, etc, for 5 days of the following week (one table per day) using Excel. An example of the assignment is available for download at the bottom of the page as well as the rubric. The tables are then to be uploaded onto a blog page: http://www.biologynutrition.wordpress.com
This method of assessment was chosen as a means to increase awareness of what each student eats daily and to compare the amount of trans and saturated fats students are eating compared to the healthy recommendation. This activity touches on the production aspect of media education and is worth 10% of the final grade (2% per table).

Extra Notes: Today’s lesson will also be integrated with a concept covered in the students’ Chemistry class: trans/cis double bonds. The students are responsible for understanding and knowing the material presented in the videos and articles for the exam at the end of the 10 lectures. Moreover, students are familiar with the structure of fats and their synthesis.

LECTURE MATERIAL:
Outline:
  • Super Size me Video (5 minutes)
  • Discussion on video (10 minutes)
  • Super Size me video Part 2 (1 minute)
  • Present the article and discuss it (20 minutes)
  • Explain the assignment, Excel, and the blog page (15 minutes)
Begin the class by showing the video below from the film “Super Size Me”. 

Explain the following terms presented in the video:
Obesity: Over nourishment, the consumption of more calories than the body needs for normal metabolism, causes obesity, the excessive accumulation of fat. Obesity, in turn, contributes to a number of health problems, including the most common type of diabetes (type 2), cancer of the colon and breast, and cardiovascular disease that can lead to heart attack and strokes.
Researchers have discovered several homeostatic mechanisms that help regulate body weight. Operating as feedback circuits, the mechanisms control the storage and metabolism of fat. Several hormones regulate long-term and short-term appetite by affecting a “satiety center” in the brain. A network of neurons relays and integrates information from the digestive system to regulate hormone release.

Cholesterol: Many hormones, as well as cholesterol, are steroids, which are lipids characterized by a carbon skeleton consisting of four fused rings. Different steroids vary in the chemical groups attached this ensemble of rings. Cholesterol is a common component of animal cell membranes and is also the precursor from which other steroids are synthesized. In vertebrates, cholesterol is synthesized in the liver. Cholesterol is crucial molecule in animals, although a high level of it in the blood may contribute to atherosclerosis. Both saturated fats and trans fats exert their negative impact on health by affecting cholesterol levels. 

Saturated and trans fat will be covered in more detail after the following article and video.

Induce a class discussion about the video and obesity.

Questions can include:
Why do people over eat (psychological aspect, not hormonal aspect of question)?
Name certain foods that promote obesity?
What solutions can you think of to decrease the percentage of people with obesity?
What restaurants do you believe promote obesity and cholesterol? (McDonalds, Burger King, Belle Province, major fast foods) 
What foods from the supermarket promote obesity and cholesterol? (Butter, chips, junk foods, etc)

Show the results of “Supersize me”.

Emphasize how crucial it is to be aware of the foods we eat and the consequences they exert on our body.
Present “A Burger a Day” Video & Article from the link below:
http://www.sciencentral.com/articles/view.php3?article_id=218391779&cat=all
Review the article with the students. The article is self-explanatory therefore no extra definitions or new concepts need to be introduced. Discuss the importance of publishing new biological discoveries in the media. Today's exercise of analyzing the article reflects the idea of "media education". It is important to be "media literate" to be able to critically analyze what is presented. If the use of sterols in our food products were more publically announced, demand for them would go up and the food industry would include sterols in their products, reducing cholesterol in our daily food intakes. Heart disease is a problem that starts at childhood and awareness must be increased through the media. Ask students: “If you went to the supermarket and had the choice between a sterol-product or sterol-free-product, which one would you choose after reading this article and watching the videos?” 

Guide the class to understand more about trans and saturated fats versus unsaturated fats.

Fatty acids vary in length and in the number and locations of double bonds. The terms saturated fats and unsaturated fats are commonly used in the context of nutrition. If there are no double bonds between carbon atoms, such a structure is referred to as saturated fatty acid. An unsaturated fatty acid has one or more double bonds. The fatty acid will have a kink in its hydrocarbon chain wherever a cis double bond exists.
Most animal fats are saturated (i.e. lard and butter) and are solid at room temperature. In contrast, the fats of fishes and plants are unsaturated and are usually liquid at room temperature (i.e. olive oil).
A diet rich in in saturated fats is one of several factors that may contribute to cardiovascular disease. Moreover, the process of hydrogenating vegetable oils produces not only saturated fats but also unsaturated fats with trans double bonds. These trans fats contribute more to cardiovascular disease than saturated fats.

To help create awareness about the foods we eat among the classroom, this assignment was designed:
Assignment Rubric


For the remaining time of the class, demonstrate to the students how to use Excel and how to post the tables on the blog page.
  • Demonstrate how to insert data on an Excel sheet
  • Demonstrate how to convert that data into a table
  • Demonstrate how to create a table using 3 different variables (part B of the assignment)
  • Demonstrate how to convert the 3 variables into a graph
  • Demonstrate how to copy & paste the table into the blog page

If there is time remaining at the end of class, allow students to begin work on their assignment.
nutrition_template_exercise.xlsx
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File Type: xlsx
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