Nutrients are molecules that provide the body with energy and materials for growth. Three kinds of nutrients you eat are called fats, proteins, and carbohydrates—terms you may have already heard. Think about what they may mean. 1.Write a brief description of what you think fats, proteins, and carbohydrates are. 2.Which of these three nutrients do you think should make up the largest part of your diet? Which should make up the smallest part? Arrange the three nutrients in order starting from the one that you should eat the most to the one that you should eat the least. 3.Why might it be unwise to eat too much of the nutrient you listed last?

Food & Nutrition Chapter 38.1

Why Do We Need Food? Eat food for: –Energy –Raw materials to building new molecules and repair body tissues Proteins for chemical reactions Phospholipids in cell membranes DNA

Nutrition  the study of food and its effects on the body Energy in food is measured by the heat it gives off when burned in the unit calories One calorie is the amount of heat energy needed to raise the temperature of one gram of water by one degree Celsius  1 Calorie = 1000 calories = 1 kilocalorie (kcal)  Average female = 2200 Calories  Average male = 2800 Calories

Essential Nutrients  supply the energy and raw materials you body uses for growth, repair, and maintenance. The nutrients that the body needs include Water Carbohydrates Fats Proteins Vitamins Minerals

Water Every cell in the human body needs water because many of the body’s processes including chemical reactions, take place in water Water loss causes problems in the circulatory, respiratory, digestive, and nervous system

Carbohydrates Major source of energy in diet Two forms: –Simple sugars (mono and disaccharides) –Complex starches – (Polysaccharides) Broken down into simple sugars in the digestive system Cellulose  Fiber –Humans cannot break down fiber  bulk helps muscles to keep food and wastes moving through your digestive and excretory system.

Fats Produced from fatty acids and glycerol Manufacture cell membranes, myelin sheaths, produce hormones, absorb fat-soluble vitamins and store energy Protect organs and insulate the body –Saturated  single bonds between carbon  maximum # of hydrogen atoms –Unsaturated  at least 1 double bond  liquid at room temperature

Proteins Provide body with material for growth Make up parts of muscles, skin and internal organs Enzymes Body can naturally produce 12 of 20 amino acids  8 remaining a.a. come from the food we eat Called essential amino acids

Vitamins Organic molecules that are needed by the body to help perform important chemical reactions 14 essential vitamins –2 types: Fat-soluble (A,D,E,K)  stored in fatty tissues of the body Water-soluble (C,B)  can’t be stored in the body

Vitamin Deficiency Scurvy –Vitamin C Deficiency Vitamin C necessary to form Collagen

Nutrient Deficiency Rickets –Vitamin D deficiency Lack of exposure to sunlight

Minerals  Inorganic nutrients that the body needs, usually in small amounts Example: Ca (bones), Fe (needed for hemoglobin), and Mg (normal functions of nerves and muscles) –Lost in sweat, urine, and other waste products

Review What is the importance of water in the body? Why is fiber an important part of your diet How are vitamins and minerals similar? –How are they different? People say, “You are what you eat!” Is there any truth to that?

include such as are made ofinclude Concept Map includeare made using Section 38-1 Nutrients CarbohydratesFatsMineralsProteinsVitamins SimpComplex Amino acids CalciumIron Fatty AcidsGlycerol SugarsStarchesFat-soluble Water- soluble

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Reading Nutritional Facts

Evaluating Food Labels Take a look at your Nutrition Facts label and answer the following questions: 1. If you ate 2 servings of this product, how many grams of fat would you eat? - How many grams of protein? 2. How many Calories in a gram of Fat? - Of protein? - Of carbohydrates? 3. On a 2000-Calorie diet, what is the Daily Value for total fat? - For sodium? - For fiber? 4. If you were an advertising agency for your product, what nutritional aspect would you want to promote and which one would you want to hide?