Nutrition: Class Content, Student Questions. Fall 2011

Transcription

1 Nutrition: Class Content, Student Questions Fall 2011

2 Nutrients Nutrients are substances the body needs to live Humans need six nutrients Three contain energy (calories) Three do not contain energy

3 Energy-Containing Nutrients Carbohydrates 4 calories per gram Protein 4 calories per gram Fat 9 calories per gram Image source: public domain

4 Nutrients Without Energy Vitamins Organic substances found in plant and animal sources A, C, D, E, K, & B vitamins (8 of them) Minerals Inorganic substances found in many of the body s structures (teeth, bones, muscles, blood cells, etc) Examples: calcium, sodium, iron, chromium, potassium

5 Student Question: Do we need all vitamins? A combination? A: We need all vitamins. What one person needs, however, will differ from another person based on their dietary behaviors. Example: person who consumes many fruits & vegetables vs fast food eater Example: a person with nutrient absorption issues may need larger doses than average individual

6 Student Question: Do we need all vitamins? A combination? Common dietary needs are those vitamins found in fruits & vegetables since many of us do not consume enough Recommendations: RDA = Recommended Dietary Allowances AI = Adequate Intake, if no RDA value set UL = Upper Limit (highest intake without negative side effects)

7 Student Question: What kinds of fruits & vegetables are most beneficial? Generally, brightlycolored produce Vitamins Minerals Antioxidants Variety Green, leafy vegetables Bright berries Tomatoes Sweet potatoes Photo: Scott Bauer, public domain

8 Student Question: What are the nutritional differences in fruits and vegetables? Both have nutrients Generally, vegetables are favored over fruits Sugar content in fruits Fructose Too much = fat storage Slower absorption rate

9 Student Question: What are the nutritional differences in fruits and vegetables? Both have nutrients Generally, vegetables are favored over fruits Sugar content in fruits Fructose Too much = fat storage Slower absorption rate

10 Student Question: Is a vegetarian Vegetarian diets can be healthy or unhealthy Whole foods: grains, vegetables, fruits, herbs Fried tofu, mashed potatoes with butter, mac and cheese, candy diet healthy?

11 Student Question: What foods are low-calorie but also filling? Carbohydrate-based foods are usually digested more quickly, resulting in hunger Since the body needs carb as its primary energy source, cutting isn t terribly helpful Complex carbohydrates take longer to digest than simple carbohydrates Brown (instead of white) rice

12 Student Question: What foods are low-calorie but also filling? Foods higher in fiber tend to take longer to digest Whole grains (barley, bran flakes, oatmeal) Nuts & seeds (almonds, flax seeds, pistachios) Fruit (raspberries, pear, strawberries, prunes) Legumes (lentils, black beans, split peas) Vegetables (peas, greens, corn, artichoke)

13 Student Question: What foods are low-calorie but also filling? Water-based foods: soups/broths Leafy green vegetables Including protein and healthy fats with carbohydrate at meals can slow digestion Eggs Fish Chicken Tofu Almond butter/peanut butter Avocado

14 Student Question: What Harms Might Vitamins Cause the Body? WebMD shows RDA or AI, and UL values for vitamins and minerals Dangers are usually associated with megadoses Besthealth

15 Student Question: What food chemicals should we look out for? Challenge: People have varying sensitivities Challenge: Often, the issue is accumulation rather than one dose at a given time Challenge: Combinations of chemicals Challenge: chemicals used for a variety of attractive purposes Challenge: some chemicals are naturally occurring (estrogenic foods)

16 Student Question: What food chemicals should we look out for? Challenge: Chemicals used for a variety of purposes attractive to consumer Preservatives Sweeteners, flavorings Fat replacers Emulsifiers, thickeners Color additives List at FDA

17 Student Question: What food chemicals should we look out for? Guideline: the more processed the food, the more chemicals present Guideline: shopping around the perimeter of a grocery store usually the healthiest approach

18 Student Question: What food chemicals should we look out for? Per Center for Science in the Public Interest Sodium nitrite Found in meat salty, processed meat products World Cancer Research Fund, May 2011: processed meats too dangerous for human consumption (totalhealthbreakthroughs.com) Saccharin, aspartame, Acesulfame-K Beverages, snack foods, dairy products, gums, soups, snacks Increased cancer risk

19 Student Question: What food chemicals should we look out for? Caffeine Addictive Stimulant properties Olestra Fat substitute in snack chips Digestive problems Reduce absorption of some fat-soluble vitamins Food dyes Blue 2, Green 3, Orange B, Red 3, Yellow 5, et. Al. Candy, baked goods, beverages

20 Student Question: What food chemicals should we look out for? High fructose corn syrup Beverages, cereals, candy, cookies, condiments Increases sweetness of food products Consumers not consuming less sugar Connection to corn allergies? Metabolic problems? (insulin resistance) Bisphenol A in cans, plastics (cancer, reproductive health, CV disease)