The Basics of Nutrition Chapter 1

Quiz Yourself True or False There are four classes of nutrients: proteins, lipids, sugars, and vitamins. T F Proteins are the most essential class of nutrients. T F All nutrients must be supplied by the diet, because they cannot be made by the body. T F Vitamins are a source of energy. T F Milk, carrots, and bananas are examples of “perfect foods” that contain all nutrients. T F

How Did You Do? False There are six classes of nutrients: carbohydrates, lipids, proteins, vitamins, minerals, and water. False Proteins are not the most essential class of nutrients. False All nutrients do not need to be supplied by the diet, because some can be made by the body. False Vitamins are not a source of energy. False Milk, carrots, and bananas are not “perfect foods.” No naturally-occurring food supplies all nutrients.

What Influences Your Eating Habits?

Why Should You Care About Your Diet? Poor diet is associated with 4 of 10 leading causes of death including: -Heart disease -Some types of cancer -Stroke -Type 2 diabetes Adequate diet plus regular exercise may reduce your chances of developing these serious chronic diseases.

Nutrition: The Basics Key Terms Diet Usual pattern of food choices Nutrients Life-sustaining substances in food Nutrition Scientific study of nutrients and how the body uses them

Nutrition: The Basics Key Terms (cont.) Chemistry Study of the composition and characteristics of matter and the changes that can occur to it Cell Smallest functioning unit in a living organism

Nutrition: The Basics Key Terms (cont.) Metabolism Chemical processes that take place in living cells Essential nutrient Nutrient that must be supplied by food Deficiency disease State of health that occurs when a nutrient is missing from the diet 8

Six Classes of Nutrients Carbohydrates Lipids (includes fat) Proteins Vitamins Minerals Water

Note approximate percentages of nutrients in young male and female bodies. Vitamins are not included, because they are in very small amounts.

Major Functions of Nutrients in the Body

What Is an Essential Nutrient? must be supplied by food is not synthesized by the body or made in amounts that meet the body’s needs

Three Key Features of Essential Nutrients If missing from diet, a deficiency disease results. Adding missing nutrient back to diet corrects signs and symptoms of the deficiency. Scientists can explain why lack of the nutrient caused abnormalities.

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What Are Phytochemicals? Substances found in plant foods that are not classified as “nutrients” but are beneficial to health. Plants make hundreds of phytochemicals.

Phytochemicals of Scientific Interest

What Lifestyle? Lifestyle is a person’s way of living such as dietary practices, physical activity habits, and use of drugs. Lifestyle choices may increase or reduce chances of developing a disease or delay its occurrence for years. 17

Early Death Possible Diseases Heart disease, certain cancers, Lifestyle Choices High fat diet + inactivity Risk Factor Obesity (excess body fat) Possible Diseases Heart disease, certain cancers, type 2 diabetes, and hypertension Early Death

Changes in Beverage Consumption

Metrics for Nutrition Units of scientific measurement often used in nutrition  Length measured in meters  Weight measured in grams  Volume measured in liters 20

Common Metric Prefixes in Nutrition

Metric Basics Conversions 1 inch = 2.5 cm 1 ounce = 28 g 1 pound = 454 g 2.2 pounds = 1 kg Do the Math  If you are 5’5” (65”) (65 x 2.5 = 162.5 cm) If you weigh 130 lbs (130 ÷ 2.2 = approx. 59 kg)

What’s a Calorie? Kilocalorie or Calorie — measure of food energy A kilocalorie is the heat energy needed to raise the temperature of 1000 g of water 1o Celsius. 1 kilocalorie = 1 Calorie = 1000 calories (Kilocalorie is abbreviated as “kcal”)

Primary Energy Sources for the Body

Macronutrients and Micronutrients -Needed in relatively large amounts -Provide energy Carbohydrates, proteins, and fats Micronutrients -Needed in very small amounts -Do not provide energy Vitamins and minerals Water: Required in large amounts but not a “macronutrient,” because it does not provide energy (calories)

Concept 1: Most Naturally Occurring Foods are Mixtures of Nutrients. A 6-oz potato contains: 4 g protein, 36 g carbohydrate <1 g fat, plus water, vitamins, and minerals 8 fluid oz fat-free milk contains: 8 g protein, 12 g carbohydrate, 1 g fat, plus water, vitamins, and minerals

Factors that Contribute to Undernutrition

Undernutrition During Life Cycle Stages - Pregnancy - Infancy - Preschool years

Undernutrition in the United States Contributing factors: - Anorexia nervosa - Alcoholism - Low income Food insecurity: - Defined as a concern about running out of food or not having enough money to buy more food. - Reported in 11% of U.S. households in 2007

Major Federally Subsidized Food Programs in the U.S.

World Food Crisis: Finding Solutions The Promise of Biotechnology Modifying living things (especially plants and animals) to make improved products Genetic Modification Techniques that alter an organism’s DNA