Nutrition: Eating for Optimum Health

Assessing Eating Behaviors What drives us to eat? Hunger Appetite Cultural and social meaning of food Habit or custom Emotional Comfort Convenience and advertising Nutritional value Social interactions

Eating for Health Nutrition The science of the relationship between physiological functions and essential elements of food Calorie Unit of measure that indicates the amount of energy we obtain from a food Americans consume more calories per person than any other group of people in the world Americans eat more fat (38%) than recommended by nutritionists (no more than 30%)

Eating for Health Characteristics of a healthy diet Adequate Moderate Balanced Varied Nutrient dense

Trends in Caloric Intake and Food Figure 9.1

Obtaining Essential Nutrients Digestive process Sequence of functions by which the body breaks down larger food particles into smaller, more usable forms Our bodies cannot synthesize some essential nutrients Some essential nutrients obtained from food

The Digestive Process Figure 9.2

Water Dehydration – abnormal depletion of body fluids The major component of blood Necessary for Electrolyte and pH balance Transporting cells and O2 Recommended amount – 8 glasses/day (64 ounces) 50-60% of body is water Is bottled water better?

Protein Second most abundant substance in humans Key to every cell, antibodies, enzymes, and hormones Transport oxygen and nutrients Role in developing/repairing bone, muscle, skin Vital for human life May need additional protein if fighting off infection, recovering from surgery or blood loss, recovering from burns

Proteins Amino acids Building blocks of protein 20 essential amino acids must be obtained from food 11 non-essential amino acids produced by the body Link together to form Complete protein – supplies all essential amino acids Incomplete protein – may lack some amino acids, but these can be easily obtained from different sources Few Americans suffer from protein deficiencies Can you give examples of complete proteins?

Complementary Proteins Figure 9.3

Calculating Your Protein RDA Figure 9.4

Carbohydrates Best fuel – provide energy quickly and efficiently Two types Simple sugars Glucose (monosaccharide) – most common form Fructose (monosaccharide) – found in fruits and berries Sucrose (disaccharide) – sources include granulated sugar, milk and milk products Complex carbohydrates (polysaccharides) Starches – from flour, pasta, potatoes Stored in the body as glycogen Fiber

Carbohydrates Carbohydrates and athletes Sugar may be counterproductive CHO ingestion is necessary for competitive long events Carbohydrate loading Myth of sugar addiction Not related in long-term studies Moderation is the key

Carbohydrates and Weight Loss High protein/low carb diets Helped educate the public about nutrients, importance of Whole grains Fiber Low-sugar food choices

Fiber “Bulk” or “roughage” Indigestible portion of plants Insoluble Found in bran, whole-grain breads, most fruits and vegetables Found to reduce risk for several forms of cancer Soluble Oat bran, dried beans, some fruits and vegetables Helps lower blood cholesterol levels Helps reduce risk for cardiovascular disease

Fiber Offers many health protections Colon and rectal cancer Breast cancer Constipation Diverticulosis Heart Disease Diabetes Obesity Most American eat far less than recommended Recommended is 20-30 grams and average is 12 grams

Fats Also called lipids Misunderstood but vital group of basic nutrients Maintain healthy skin Insulate body organs Maintain body temperature Promote healthy cell function Carry fat-soluble vitamins A, D, E, and K Are a concentrated form of energy

Obtaining Essential Nutrients Triglycerides make up 95% of total body fat Remaining 5% composed of substances like cholesterol Can accumulate on inner walls of arteries and contribute to cardiovascular disease Ratio of cholesterol HDL/LDL helps determine risk for heart disease Saturated vs. unsaturated fat Saturated mainly from animal sources, solid at room temperature Unsaturated generally come from plants and usually liquid at room temperature

Percentages of Saturated, Polyunsaturated, and Monounsaturated Fats in Common Vegetable Oils Figure 9.5

Obtaining Essential Nutrients Avoiding trans fatty acids Created by process of making liquid oil into a solid Increase LDL levels while lowering HDL levels Higher risk of coronary and heart disease, sudden cardiac death Found in many margarines, baked goods and restaurant deep-fried foods Food labels listing no trans fasts can still contain less than 500 milligrams/serving

Obtaining Essential Nutrients Still need essential fatty acids Eat fatty fish Use healthier oils (including olive oil) Eat green leafy vegetables Walnuts, walnut oil Ground flaxseed

Obtaining Essential Nutrients Use moderation with fat intake Read food labels Use olive oil for cooking Avoid margarine with trans fatty acids Choose lean meat, fish, poultry Eat fewer cold cuts, less bacon, sausages, hot dogs, organ meats Choose nonfat dairy products Use substitutes for higher-fat products Think of your food intake as an average, over a day or two—if you have a heavy breakfast, eat a light dinner

Vitamins Potent, essential, organic compounds Promote growth, help maintain life and health Two types Fat soluble – absorb through intestinal tract with fat A, D, E, and K Water soluble – dissolve in water B-complex and C

Vitamins Few Americans suffer from vitamin deficiencies Often, vitamin supplements not necessary Too much of many vitamins can be harmful Why do you think so many people take vitamin supplements?

Minerals Inorganic, indestructible elements that aid the body Vitamins cannot be absorbed without minerals Macrominerals are needed in large amounts Sodium, calcium, phosphorus, magnesium, potassium, sulfur, chloride Trace minerals are needed in small amounts Iron, zinc, manganese, copper, iodine Excesses or deficiencies of trace minerals can cause serious problems

Determining Nutritional Needs Recommended Dietary Allowances (RDAs) Adequate Intake Daily Values Recommended Daily Intakes (DRIs) Daily Reference Values (DRV) Reading food labels can help determine needs

Reading a Food Label Figure 9.6

ABC News: Nutrition Discussion Questions Play Video | Nutrition Discussion Questions Discuss whether you think manufacturers are intentionally misleading consumers regarding serving size listings on their products. Why or why not? What kinds of standards for food labeling would you recommend to manufacturers?

The New MyPyramid Food Guide Replaced the food guide pyramid to account for varied nutritional needs throughout the U.S. population Emphasizes Personalization www.mypyramid.gov Gradual improvement Physical activity Variety Moderation Proportionality

The MyPyramid Plan Figure 9.7

Serving Size Card Figure 9.8

Nutritional Needs for Different Groups Figure 9.9

Vegetarianism: Eating for Health MyPyramid Plan adaptable for a vegetarian diet Types of vegetarian diets Vegan Lacto-vegetarian Ovo-vegetarian Lacto-ovo-vegetarian Pesco-vegetarian Semivegetarian

Vegetarianism: Eating for Health Reasons why 5-15% of the population are vegetarians Aesthetic Animal rights Economic Personal Health Cultural Religious

The Medicinal Value of Food Compelling evidence that diet may be as effective as drugs Functional Foods Antioxidants Carotenoids

The Medicinal Value of Food Folate Form of vitamin B Folate fortification 1998 Neural tube defects Heart disease Probiotics Found in fermented milk products

Supplements Dietary supplements Products taken by mouth to supplement existing diets Includes vitamins, minerals, herbs FDA does not evaluate supplements prior to their marketing; companies responsible for own monitoring If in doubt about supplements, simply eat from the major food groups A multivitamin added to a balanced diet will generally do more good than harm

Gender and Nutrition Men and women have different needs Women have cyclical changes Men have more lean tissue (burn more)

Changing the “Meat-and-Potatoes” Diet Reasons to change Heavy red meat eaters are five times more likely to get colon cancer, and twice as likely to develop prostate cancer Fruits and vegetables reduce stroke risk as well as risk for oral, bladder, and pancreatic cancers Cancer of the esophagus is one of the fastest rising malignancies in the U.S., among white men in particular

Improved Eating for the College Student Variety of challenges for healthy eating Eating breakfast and lunch vital for keeping energy up throughout the day Make lunch and bring it with you, including healthy snacks Will keep you from buying less healthy food on the run Limit sugar-heavy beverages and fried products

Improved Eating for the College Student Nutritional eating on a budget can be done Buy vegetables locally and in season Use coupons or shop at discount or bulk food stores Your city or county health department may have suggestions if you don’t have the funds to eat properly

Food Safety: A Growing Concern Food-borne illness Affects millions of people each year Responsible for 5,000 deaths a year Signs Cramping Nausea Vomiting Diarrhea

Food Safety: A Growing Concern Key factors why food-borne illness has increased Globalization of food supply Inadvertent introduction of pathogens to new geographic regions Exposure to unfamiliar food-borne hazards Changes in microbial populations Increases susceptibility of varying populations Insufficient education about food safety

Food Safety: A Growing Concern Practice responsible food handling at home Keep hot foods hot, and cold foods cold Freeze or eat fish, poultry, or meats within 1 or 2 days Eat leftovers within 3 days Wash hands, cutting boards, counters, and knives well Use a meat thermometer Never thaw foods at room temperature

Food Irradiation: How Safe Is It? Approved by USDA in February 2000 Use gamma irradiation from radioactive cobalt, cesium, or other X-ray sources Breaks chemical bonds in the DNA of bacteria Rays essentially pass through the food Lengthens product shelf-life, prevents spread of microorganisms Reduces need for toxic chemicals currently used Marked with the “radura” logo

Food Additives Reduce food-borne illness Enhance nutrients Intentional food additives Antimicrobial agents: salt, sugar, nitrates Antioxidants: preserve color and flavor Artificial color, nutrient additives, flavor enhancers Sulfites Dioxins: found in coffee filters, milk containers, and frozen foods Methylene chloride: found in decaffeinated coffee Hormones: bovine growth hormone found in animals

Food Allergies and Intolerances Abnormal response to a food triggered by the immune system Found in 5% of children and 2% of adults Occurs when the body treats a food, usually protein, as an invader Initial signs include rapid breathing or wheezing, hives, rash, eczema, or runny nose More dramatic symptoms: facial swelling or respiratory problems (anaphylactic reaction) Anaphylactic reaction requires a shot of epinephrine, a hormone that stimulates the heart Can be mistaken for food intolerance or reactions to food additives

Food Allergies and Intolerances Food intolerances Less dramatic reaction than food allergies Not the result of immune system response Generally shows as gastric upset Lactose intolerance common, also happens in response to food additives (MSG, sulfites, gluten) May have psychological triggers

Organic Food developed, grown, or raised without use of synthetic pesticides, chemicals, or hormones Becoming much more common

Organic Foods need to meet criteria set by USDA to be certified organic Produced without hormones, antibiotics, herbicides, insecticides, chemical fertilizers, genetic modification, or germ-killing radiation Monitoring systems still under development Some concern that buying organic means buying foods with less nutrients Buy close to home, get it in the refrigerator quickly Is buying organic really better?