Nutrition, Metabolism, and Diabetes

Background Information

The over-arching objective for this curriculum unit is for students to understand and experience the connection between nutrition, exercise, and one's ability to learn. The aforementioned rates of obesity are quite alarming and indicate a clear need to address food choice, yet research also points to a link between exercise and academic achievement. Physical activity enhances brain functioning. In a study of the effects of physical education classes on elementary school testing results, Pamela Tremarche and her colleagues state, "Research has shown that exercise provides more oxygen-rich blood, which nourishes the brain. More neurotransmitters are released, more endorphins are released, and more neural networks are developed with movement." ⁶ Many studies of late have focused on obesity, student performance in school, and the need to increase funding for physical education programs. Often, in situations where money is scarce, physical education is one of the first "amenities" to be cut from school districts because it is not measured by state assessments. Nonetheless, "Research indicates that physical activity enhances brain functions and produces many cognitive and physiological benefits. Children who are provided with many experiences at an early age develop an abundance of neurons and are better learners ⁷.

Tremarche's study, conducted in Massachusetts, found that the fourth grade students who were given access to more physical education classes in a school year scored higher on an English/Language Arts achievement exam ⁸. Similarly, in a study performed with high school students, those who engaged in high levels of exercise experienced less depression, had stronger relationships with their parents, were more involved in sports teams, had better grades, and did not use drugs as often as their peers who had low levels of physical activity ⁹. Likewise, a report released by "Action for Healthy Kids" claims, "Intense physical activity programs have positive effects on academic achievement, including increased concentration; improved mathematics, reading, and writing test scores; and reduced disruptive behavior" ¹⁰. In sum, "the function and development of the mind is influenced by the health and care of the body." ¹¹

In yet another study called the 2003 Children's Lifestyle and School-performance Study (CLASS) 5200 fifth grade students in Nova Scotia were part of a sample group in order to study the relationship between diet quality and academic performance. Findings indicate a link between diet quality and achievement; those students with diets rich in fruits and vegetables and a modest intake of fat out-performed their peers ¹². Many researchers and advocates for public education, in turn, argue for the need to implement obesity prevention programs, health education, and health services, in addition to offering more nutritious foods to children in the school setting ¹³. In a review of nine articles addressing this theme scholars have found that overweight and obesity are related to a decrease in academic achievement. "Overweight and obese children are more likely to have low self-esteem and they have higher rates of anxiety disorders, depressions, and other psychopathology. These mental health conditions may be the mediating factors for an overweight or obese child to score poorly in school" ¹⁴. All of these facts point to two needs: an emphasis on nutrition education and an increase in time spent engaged in physical activity.

Using this research and my students' needs as a guide, I will teach/review with the students the basic principles about food groups or categories, as per both the USDA's MyPyramid and the Harvard School of Public Health's New Healthy Eating Pyramid. The major groupings vary between the two pyramids but are as follows: whole grains, fruits and vegetables, meat and beans, dairy/milk, plant oils, nuts, legumes, fats, starches and sweets. In an effort to assist the students in eating a healthy, balanced diet, we will discuss how the nutrients in food provide us with the energy we need to live and to operate our body's systems. All food contains nutrients, including carbohydrates, proteins, fats, vitamins, and/or minerals. Carbohydrates provide us with energy, as do fats and we need proteins to make and repair cells. We will discuss how you can use the two food pyramids as a guide for what to eat and how much to eat. Fresh vegetables and fruits are a great source of vitamins. Whole grains (which are readily available, tasty, and inexpensive) are better for your body than products simply containing refined white flour. Fats are an essential part of a healthy diet, but a balanced regime contains more unsaturated fats than saturated fats. Fats from fish, nuts, seeds, and oils are unsaturated, while the fats in many pre-packaged dessert foods and snacks are saturated.

In addition, I will review the process of digestion with students. Human digestion, according to state standards, is addressed in second, third, and fourth grades in New Mexico. I will use videos, pictures, and grade-level nonfiction texts to review this material with the students. We will discuss how digestion begins in the mouth with saliva, continues in the esophagus, and moves into the stomach where our food is churned by a process known as peristalsis. Two neighboring organs, the liver and the pancreas, make chemicals that assist in turning the food into a mushy substance. Then, the food is broken down even further in the small intestine and nutrients are absorbed into the blood. I will also help students understand how during this process what we eat is converted to a green and brown substance called chyme: molecules are extracted and absorbed from chyme for use as fuel in our bodies.

In conjunction with a discussion of nutrients and digestion will be a series of activities about the importance of exercise in maintaining a healthy lifestyle. Food choice and exercise are linked. Leading a healthy lifestyle not only involves eating a balanced diet but also remaining physically active. Exercise has many benefits, including, reduced risk of disease, increased heart rate which results in increased blood flow and subsequent increased oxygen flow to the brain, a decrease in stress levels, increased metabolism, a boost in the immune system, and a burning off of calories. Body systems become more efficient with regular exercise. Because of these benefits, it is recommended that youth and adults get at least thirty minutes of exercise each day.

All food contains calories. The number of calories in a food is a measure of the amount of energy that can be extracted from it. Therefore, food calories are directly related to calories used by activity. Because of this relationship, calories taken in (in food) must equal calories out (in activity) in order for a person to maintain his/her weight. Similarly, if the calories consumed outnumber those expended, weight will be gained and if the calories burned are more than those ingested, a person will lose weight. Through a balanced diet and sufficient exercise, a person can help regulate his/her weight and help his/her body perform at its best.