1. Chapter 1
What Is Nutrition?

2. Objectives for Chapter 1
Discuss the factors that influence food choice.
Define the term nutrition.
Describe how nutrition affects your health.
Name and explain the six categories of nutrients found in food and in the body.
Differentiate between the three energy nutrients: carbohydrate, protein, and fat.
Calculate the calorie content of a food based on the grams of carbohydrate, protein, and fat.
Understand the important roles that vitamins, minerals, and water play in your diet.
Understand the scientific method that is involved in nutrition research.
Discuss the current nutritional state of the American diet.

3. What Drives Our Food Choices?
We need to eat and drink to obtain:
Nutrients: chemical compounds in foods to provide:
fuel for energy (measured in kilocalories)
growth
maintenance
Regulate body processes

4. Copyright © Cengage Learning. All rights reserved
Energy
Capacity to do work or to produce heat.
The total energy content of the universe is constant.
PHET:Energy forms and changes
PHET:Energy Skate Park(adv)
Different types of energy:
Charging up vs eating up:
Copyright © Cengage Learning. All rights reserved

5. Grouping our food. http://www.phytochemicals.info/phytochemicals.php
There are Six classes:
Carbohydrates
Fats
Protein
Vitamins
Minerals
Water
Phytochemicals: non-nutrient compounds that contribute to health and may play a role in fighting chronic diseases. They are found in fruits, vegetables, grains, beans, and other plants.

6. What Are the Essential Nutrients and Why Do You Need Them?
The six classes of nutrients are all essential in the diet
Macronutrients: energy-yielding nutrients needed in higher amounts
Carbohydrates (when broken down provide glucose)
lipids (fats)
proteins
Micronutrients: needed in smaller amounts
Vitamins and minerals
Copious amounts of water needed daily
Alcohol provides calories but is not an essential nutrient
Taste Buds:

7. What Drives Our Food Choices?
We choose foods for many other reasons beyond the basic need to obtain nutrients:
Taste and culture
Social reasons and trends
Cost, time, and convenience
Habits and emotions
See Do Outside Factors Influence Your food choices? P. 6

8. What Is Nutrition and Why Is Good Nutrition So Important?
Nutrition: a science that studies how nutrients and compounds in foods nourish and affect body functions and health
Chronic deficiencies, excesses, and imbalances of nutrients can affect health, both short-term and long-term
Good nutrition plays a role in reducing the risk of many chronic diseases and conditions, including heart disease, cancer, stroke, diabetes, osteoporosis, high blood pressure, and obesity

9. Table 1.1

10. Earth’s Chemical Composition

11. Nutrients in Foods and in the Body
Figure 1.2

12. Nutrients and Their Functions
Figure 1.3

13. What Are the Essential Nutrients and Why Do You Need Them?
Carbohydrates, fats, and proteins
Provide energy
Carbohydrates and protein provide 4 kcal/gram
Fats provide 9 kcal/gram = 9 Cal/g
Are organic compounds (contain carbon atoms)
Also contain hydrogen and oxygen atoms
Proteins also contain nitrogen atoms (unlike carbohydrates and fats)

14. What Are the Essential Nutrients and Why Do You Need Them?
Carbohydrates supply glucose, the major energy source.
Should be the majority of your diet
Fats (lipids) are another major fuel source and also:
Cushion organs
Insulate body to maintain body temperature
Proteins provide energy but are better suited for:
Growth and maintenance of muscle, tissues, organs
Making hormones, enzymes, healthy immune system
Transporting other nutrients

15. What Are the Essential Nutrients and Why Do You Need Them?
Vitamins and minerals are essential for metabolism but are calorie free!
Many assist enzymes (enzymes speed up reactions but are not part of the reaction)
Example: B vitamins are coenzymes in carbohydrate and fat metabolism
Vitamins are organic compounds
Minerals are inorganic substances

16. Vitamins vs Minerals
Vitamins ("vita" = life and "amine" = containing nitrogen) are organic (containing carbon, which is an element found in all living things)
Each of these vitamins have unique roles and functions in our bodies. Example, vitamin A promotes eyesight and vitamin K helps blood to clot.
Fat Soluble: Vitamins A, D, E, K
Water Soluble: Folate, Niacin, B6(Pyridoxine), B12, B2(Riboflavin), C, B1(Thiamin), Folic Acid, Pantothenic Acid

17. Vitamins vs Minerals
Minerals are pure inorganic elements like calcium, potassium, iron etc.
Play vital roles in the body, such as calcium in osteoporosis prevention and iron in (iron-deficiency) anemia prevention.
Other minerals, such as lead, are harmful.

18. What Are the Essential Nutrients and Why Do You Need Them?
Water is vital for many processes in your body
Part of fluid medium inside and outside of cells
Helps chemical reactions, such as those involved in energy production
Key role in transporting nutrients and oxygen to cells and removing waste products
Lubricant for joints, eyes, mouth, intestinal tract
Protective cushion for organs
Temperature control

19. How Should You Get These Important Nutrients?
The best way to meet your nutrient needs is with a well-balanced diet
Composed of a variety of foods, providing:
Essential nutrients from all six classes
Fiber and phytochemicals
Whole grains, fruits, and vegetables are rich sources

20. How Should You Get These Important Nutrients?
You can meet some nutrient needs with a supplement
When nutrient needs are higher
Example: Pregnant women need an iron supplement to meet increased needs
When diet restrictions exist
Example: Lactose-intolerant individuals (difficulty digesting milk products) may choose a calcium supplement to help meet needs
Well-balanced diet and supplements are not mutually exclusive; they can be partnered for good health

21. Calorie Count: Eat by the Numbers
Discussion: Can people’s diet change with information?

22. Calorie Count: Eat by the Numbers
Discussion Questions
Would knowing the amount of calories effect your food choices?
How far should government go in helping you make healthy choices?
What if addiction to foods is as addictive as drugs?

23. How Does the Average American Diet Stack Up?
Average American diet is high in:
Sodium
Saturated fat
Calories
Average American diet is low in:
Vitamin E
Calcium
Fiber

24. How Does the Average American Diet Stack Up?
Incidence of overweight and obesity is on the rise
65 percent of American adults and 15 percent of children (ages 6 to 19) are overweight
Take in more calories than needed
Burn fewer calories due to sedentary lifestyles
Resulting in increased rate of type 2 diabetes (especially children), heart disease, cancer, and stroke

25. How Does the Average American Diet Stack Up?
Figure 1.4

26. What’s the Real Deal When It Comes to Nutrition Research and Advice?
Newspaper headlines and television news items report results of a single, recent research study
Advice from authoritative health and nutrition organizations is based on:
Consensus: the opinion of group of experts based on collection of information

27. Evaluating Media Headlines with a Critical Eye
Before making dietary and lifestyle changes based on media reports, read with a critical eye and ask:
Was the research finding published in a peer-reviewed journal?
Was the study done using animals or humans?
Do the study participants resemble me?
Is this the first time I’ve heard about this?
Wait until research findings are confirmed and consensus reached by reputable health organizations before making changes

28. The scientific Method

29. Steps of the Scientific Method
Figure 1.5

30. A Hypothesis Can Lead to a Scientific Consensus
Figure 1.6

31. Research Studies and Experiments Confirm Hypotheses
Observational Research: involves looking at factors in two or more groups of subjects to see if there is a relationship to certain health outcomes
Epidemiological research: study of populations of people
Example: Relationship of sun exposure and incidence of rickets in Norway compared with Australia
May be due to other unidentified diet or lifestyle factors

32. Research Studies and Experiments Confirm Hypotheses
Experimental Research: involves at least two groups of subjects
Experimental group: given a specific treatment
Control group: given a placebo (“sugar pill”)
Double-blind placebo-controlled experiment is “gold standard”
Neither scientists nor subjects know which group is receiving which treatment
All variables held the same and controlled for both groups

33. Controlled Experiments
Figure 1.7

34. Describe an experiment you would design to test the following hypothesis: Vitamin C supplements cure colds .
Find a large sample size with colds
Divide them randomly into 2 groups
One gets vitamin C, the other gets a placebo
Double Blind!
Experiment is observed
Compare groups

35. What Is Nutritional Genomics?
Genes determine your inherited, specific traits
Made of DNA, which contains the genetic instructions for making proteins that direct activities in the body
Nutritional Genomics: study of how specific food components affect gene expression in your cells and thereby your health
Example: may help determine the specific dietary combination of fats needed to lower your risk of heart disease based on your unique genetic make-up