Nutrition, Health, and Fitness Chapter 7 Do you understand how to fuel your body?
Why is Nutrition Important? • Nutrition – the study of food and the way the body uses it. • Consume too much or too little of any of the essential nutrients and it will eventually lead to health problems. • In the past more peoples problems were from dietary deficiencies (scurvy, Vit C) (anemia, Iron). This was a result of malnourishment. This problem still exists but not from a lack of availability to most people.. • Today the problem has become over-nourishment of the wrong food sources. Diets high in calories, sugar, fats, sodium. • These diets are linked to CVD, Cancer, Obesity, Diabetes.
What are Nutrients? Nutrients are basic substances in foods that your body uses to maintain health. Macronutrients – carbs, fats, proteins • Needed in greater amounts • Used to build and maintain body tissue • Also provide energy for daily activity (kilocalories – calories)
Carbohydrates Whole grains, pasta, fruits, and vegetables. • 4 calories per gram • 50-60% of your calories (80-90% should come from complex carbs) see figure 1 • Primary source of energy during physical activity Simple Carbs • Glucose – sugar that can be used directly by the body. • Glycogen – storage form of glucose in the liver and muscles • Glucose that is not immediately used for energy or stored as glycogen will be stored as fat. Complex Carbs • Must be converted to glucose before it can be used by the body for fuel. • This should be the main source of your carb intake. • Starches are long chains of glucose units and important for physical activity. Fiber is not an energy source and helps with the elimination of food waste reducing the risk of colon cancer. • Fiber is very important in the removal of cholesterol lowering the risk of coronary heart disease. • Minimum 25 grams of fiber a day.
Fats and Lipids Fat is a type of lipid, cholesterol is also a lipid. Fat • Stored for energy usage • 9 calories per gram • Body stores excessive fat in fat cells in the body, also converts excessive carbs and protein into fat for storage. • Dietary fat is essential for normal growth and healthy skin, also necessary for protection of internal organs. • Assists in absorbing, transporting, storing fat-soluble vitamins.
Unsaturated Fats – mono and polyunsaturated • Found in plants • Liquid at room temperature • Thought to be the most heart healthy. • Omega-3 fatty acid (helps lower cholesterol and triglycerides) • Grass Feed vs Grain Feed Beef Saturated Fats • Solid at room temperature. • Comes mostly from animal sources. Trans Fats • Found in fried and baked foods. • Tend to raise cholesterol. • Has been banned in some states.
Other Types of Lipids In addition to fat there are two other types of lipids. Phospholipids and sterols • Both play important roles in your body. Cholesterol • Produced by the body and found in animal foods • LDL “bad” cholesterol – contains large amounts of cholesterol and promotes fatty plaque buildup in the arteries. • HDL “good” cholesterol – contains large amounts of protein and cuts down on the plaque buildup.
Good fats are mostly found in: • Fish • Seeds/nuts • Vegetable oils Unhealthy fats are mostly found in: • Fatty meats • Butter and lard • Fried foods Dietary Cholesterol • Found in many foods but your body produces all that it needs naturally. • Diets high in saturated fats will cause the body to produce more than normal levels.
Proteins • The primary role of proteins is to serve as the structural unit to build and repair cells and body tissues. • Protein also plays an important role in the synthesis of enzymes, hormones, and antibodies. • Should not be used as a major fuel source. Good Sources of Protein: • Turkey or chicken with the skin removed, or bison (also called buffalo meat) • Lean cuts of beef or pork, such as round, top sirloin, or tenderloin (trim away any visible fat) • Fish or shellfish Other good sources of protein include: • Pinto beans, black beans, kidney beans, lentils, split peas, or garbanzo beans • Nuts and seeds, including almonds, hazelnuts, mixed nuts, peanuts, peanut butter, sunflower seeds, or walnuts (just watch how much you eat, because nuts are high in fat) • Low-fat dairy products
Micronutrients • Need in smaller amounts • Essential for numerous process such as regulating cell function
Vitamins Play an important role in many bodily functions such as regulation of growth and metabolism. • Water soluble • Fat soluble • See table 2 (pg. 191)
Minerals Chemical elements required by the body for normal function. • Serve as a structural function for teeth and bones • Body functions such as nerve impulses, muscular contraction, etc • See table 3 (pg. 192)
Water Makes up 60-70% of our bodies. • Temp regulation • Digestion • Waste elimination • Blood formation
Dietary Must!!! • Eat more fruits, vegetables, and whole grains. • Limit your intake of calories, sugar, alcohol, fat, sodium This will provide your body with the appropriate calories, vitamins, and minerals.
Antioxidants Vitamins and micronutrients that protect cells by preventing oxidation. • They neutralize free radicals before they can damage cells. • Found in fruits and vegetables
Phytochemicals “A Closer Look” pg. 207 Substances found in plant foods. • Appear to protect against cancers, heart disease, and other chronic conditions.
Dietary Supplements Not regulated by a governing body. • Consume these with great caution. • Don’t assume your Dr. has done his research regarding these. Just like medicines they are given “gifts” to push these items on patients. • Do your own research. How much should be done.
Topics in Food Safety and Technology • Foodborne Illness • Food Additives • Antibiotics, Hormones, and Organically Grown Foods • Irradiated and Bioengineered Foods See Videos on Class Webpage; 1. Polyface Farms 2. The Truth About Organic Food 3. Genetic Roulette