Chapter 5.2 & 5.3 Nutrients

Objectives Define nutrients (carbohydrates, proteins, fats, vitamins, minerals, water) and describe their roles in maintaining good health. Identify food sources of all the nutrients. Contrast simple & complex carbs, complete & incomplete proteins, saturated & unsaturated fats, and water-soluble & fat-soluble vitamins

Carbohydrates The body’s preferred source of energy Contain 4 calories per gram 55-65 % of calories should be from carbs

Carbohydrates 1. Simple- sugars Fruits-Fructose Milk-Lactose Grain-Maltose Sugar-Sucrose

Carbohydrates 2. Complex- Starches Sources: grains (rice, wheat, corn, oats, seeds, nuts, legumes (peas & beans), tubers (potatoes) Chemically more complex than simple carbs, starches break down into sugars

More Carbs Glucose- simple sugar & body’s main fuel, all carbs must be converted into it for energy Glycogen- excess glucose stored in the muscles & liver as this starch-like substance Extra carbs not stored as glycogen are stored as adipose tissue or body fat

Fiber- complex carb that cannot be digested and used for energy Found in vegetables & fruits, seeds, whole-grains (cereal, bread, pasta, rice, oats, corn) Recommended to eat 25 grams per day Helps move waste through the digestive system Helps prevent constipation, appendicitis, & cancers Helps control heart disease (lowers blood cholesterol) & diabetes (controls blood sugar) Aids weight loss, makes you feel full and no calories

Protein Helps build & maintain body tissues (muscle, bone, connective tissues, organs, blood, cells) Contain 4 calories per gram 10-15 % of calories should be from protein Excess protein is converted & stored as fat

Functions of Protein Build body tissues during periods of growth & repair damaged body cells Make Up: Enzymes- control the rate of biochemical reactions Hormones- regulate reactions Antibodies- identify & destroy bacteria and viruses

Amino Acids Building blocks that make up proteins 20 different types (body makes 11 of them) Essential amino acids- the other 9 types that must come from foods you eat

Incomplete Proteins- foods that lack some essential amino acids Complete Proteins- foods that contain all the essential amino acids (meat, poultry, fish, eggs, dairy, soybean) Incomplete Proteins- foods that lack some essential amino acids Must eat a variety of plant products to get all the essential amino acids (eat a variety plant products including legumes, grains, nuts/seeds)

Fats Most concentrated source of energy Contain 9 calories per gram Not more than 30% of daily calories from fat Made of fatty acids Lipid- fatty substance, does not dissolve in water

Saturated-fatty acid full of hydrogen atoms it can, solid a room temperature Associated with increased risk of heart disease Found in animal fats & tropical oils (palm, coconut) Unsaturated- fatty acid missing one or more hydrogen atoms, liquid or oil at room temp Found in vegetable oils (olive, canola, corn) Hydrogenation- process of adding missing hydrogen atoms (become saturated & solid)

Role of Fats Carry vitamins ADEK in blood Source of Linoleic Acid- essential fatty acid not made in the body (needed for healthy skin) Adds flavor to foods Take longer to digest making you feel full Too much fat linked to obesity, heart disease

Cholesterol- fatlike substance produced in liver of all animals (only in foods of animal origin) Needed to produce sex hormones, vitamin D (with sunlight), protective sheath of nerves Consumption of saturated fats increases blood cholesterol levels

Micronutrients- needed in very small amounts Vitamins- compounds that help regulate body processes (digestion, absorption, metabolism) Do NOT supply calories, BUT some speed up reactions that produce energy in cells 13 total Vitamin D only one manufactured in the body Micronutrients- needed in very small amounts

Water-Soluble (B, C) dissolve in water Not stored in the body, extra excreted in the urine, needed every day Fat-Soluble (ADEK) absorbed by fat Stored in body fat, liver, kidneys Can possibly be toxic or damage body

Minerals Inorganic substances that act as catalysts regulating many vital body functions Trace Minerals- need tiny or trace amounts

Iron- hemoglobin that carries oxygen in blood Calcium- bone strength, muscle contractions, blood clotting, nervous system (dairy products) Body takes calcium from your bones if not eating enough in the diet May lead to osteoporosis (brittle weak bones)

Electrolytes- (Sodium, Chloride, Potassium) Become electrically charged in solutions Help maintain the balance of fluid in the body cells Important for hydration (Gatorade) since they are last during perspiration or sweating

Water A regulator that is vital to every body function Transports nutrients and wastes to & from cells Lubricates joints & mucous membranes Also: digestion, eliminate wastes, perspiration Makes up 60-70% of your body