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PowerPoint® Lecture Outlines prepared by
Dr. Lana Zinger, QCCCUNY
9
Nutrition and
You
Copyright © 2011 Pearson Education, Inc.
Assessing Eating Behaviors: Are You What You Eat?
 What Drives Us to Eat?
• Hunger
• Appetite
• Cultural and social meaning attached to food
• Convenience and advertising
• Habit or custom
• Emotional comfort
• Nutritional value
• Social interactions
• Regional/seasonal trends
Copyright © 2011 Pearson Education, Inc.
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
 Characteristics of a Healthy Diet
• Adequate
• Moderate
• Balanced
• Varied
• Nutrient dense
Copyright © 2011 Pearson Education, Inc.
Estimated Daily Caloric Needs
Copyright © 2011 Pearson Education, Inc.
Trends in Per Capita Nutrient Consumption
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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 are obtained from food.
Copyright © 2011 Pearson Education, Inc.
The Digestive Process
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Obtaining Essential Nutrients
 Water: A Crucial Nutrient
• 50 to 60 percent of the body is water
• Too little water can cause dehydration, an abnormal
depletion of body fluids.
• Too much water can cause hyponatremia, a decreased
concentration of sodium in the blood
• Water is necessary for:
• Electrolyte and pH balance
• Transporting cells and molecules
• Recommended amount is 8 glasses/day (64 ounces)
• Is bottled water better?
Copyright © 2011 Pearson Education, Inc.
Bottled Water Boom: Who Pays the Price?
 Environmental Consequences
• Factories use about 18 million barrels of oil and 130 billion
gallons of fresh water to make bottled water.
• Systems such as reverse osmosis purifiers use about 2 liters of
fresh water running through a system.
• About 900,000 tons of plastic is needed to package bottles.
• Negative health risks are found in plastic bottles in bisphenol A
(BPA), a component in some plastics.
• Bottled water is considered a “food” and requires much less
frequent monitoring by the FDA for safety than tap water.
• In California alone, more than 1 billion water bottles are thrown
into the trash.
• Entire populations are being left vulnerable to water shortages.
Copyright © 2011 Pearson Education, Inc.
Bottled Water Boom: Who Pays the Price?
 To Help to Curb the Environmental Threats:
• Don’t buy bottled water; instead use reusable stainless
steel containers.
• When you have parties, use covered pitchers of ice
water.
• Buy a water filter.
• Recycle any plastic bottles you use or see.
• Become involved in initiatives to ensure quality tap
water in your community.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Proteins
• Second most abundant substance in humans next to
water
• Key to all cells, antibodies, enzymes, and hormones
• Transport oxygen and nutrients
• Important role in developing/repairing bone, muscle,
and skin
• Vital for human life
• May need additional protein if fighting off infection,
recovering from surgery or blood loss, or recovering
from burns
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Amino acids
• Building blocks of protein
• 20 essential amino acids must be obtained from food.
• 11 nonessential amino acids are 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?
Copyright © 2011 Pearson Education, Inc.
Complementary Proteins
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Carbohydrates
• Are the best fuel source and provide energy quickly and efficiently
• Simple Carbohydrates
• Glucose (monosaccharide)—most common form
• Fructose (monosaccharide)—fruit sugar
• Sucrose (disaccharide)—granulated table sugar
• Lactose (disaccharide)—milk sugar
• Maltose (disaccharide)—malt sugar
• Complex Carbohydrates (polysaccharides)
• Starches—grains, cereals, and vegetables
• Stored in the body as glycogen
• Fiber—“bulk” or “roughage”
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Fiber
• Insoluble
• Found in bran, whole-grain breads, and most fruits
and vegetables
• Found to reduce risk of several forms of cancer
• Soluble
• Found in oat bran, dried beans, and some fruits and
vegetables
• Helps lower blood cholesterol levels
• Helps reduce risk of cardiovascular disease
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
• Benefits of fiber include protection against
• Colon and rectal cancer
• Breast cancer
• Constipation
• Diverticulosis
• Heart disease
• Diabetes
• Obesity
• Recommended amount is 20 to 35 grams/day
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Glycemic Index (GI) and Glycemic Load (GL)
• The Glycemic Index is a system for rating the potential
of foods to raise blood glucose levels.
• Foods that break down quickly and result in fast blood
glucose surge have a high GI index rating.
• Combining carbohydrates with fats and proteins can
lower the overall GI.
• Glycemic load refers to the amount of carbohydrates in
the food you eat multiplied by the glycemic index of
that food.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Fats
• Also called lipids
• Misunderstood but a 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
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
• Triglycerides make up 95 percent of total body fat
• Cholesterol makes up 5 percent of total body fat
• Can accumulate on inner walls of arteries and
contribute to cardiovascular disease
• Ratio of cholesterol HDL/LDL helps determine risk
for heart disease
• Types of Dietary Fat
• Saturated are mainly from animal sources and are
solid at room temperature.
• Unsaturated generally come from plants and are
usually liquid at room temperature.
Copyright © 2011 Pearson Education, Inc.
Percentages of Saturated, Monounsaturated,
Polyunsaturated, and Trans Fats in Common Vegetable Oils
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Avoiding Trans Fatty Acid
• Created by process of making liquid oil into a solid
• Increase LDL levels while lowering HDL levels
• Eating trans fat increases risk of coronary and heart
disease and sudden cardiac death
• Found in many margarines, baked goods, and restaurant deepfried foods
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
• New Fat Advice: Is More Fat Ever Better?
• According to the American Heart Association, eating
fewer than 15 percent of our calories as fat can
actually increase blood triglycerides.
• Eat fatty fish.
• Use healthier oils (including olive oil).
• Eat green, leafy vegetables.
• Eat walnuts and use walnut oil.
• Eat ground flaxseed.
Copyright © 2011 Pearson Education, Inc.
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, and poultry.
• Eat fewer cold cuts and less bacon, sausages, hot
dogs, and 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.
Copyright © 2011 Pearson Education, Inc.
ABC News Video: Going Green
| Going Green
Discussion Questions
1. What can farmer’s markets do for a community?
2. Is it healthier to purchase from a farmer’s market? Is
there a difference in nutritional value?
Copyright © 2011 Pearson Education, Inc.
Toward Sustainable Seafood
• More than 70 percent of the world’s natural fishing grounds
have been overfished.
• High levels of chemicals, parasites, bacteria, and toxins are
now found in seafood.
• Mercury, a waste product of many industries, binds to
proteins and stays in an animal’s body.
• Mercury can cause damage to the nervous system and
kidneys, and cause birth defects.
• Polychlorinated biphenyls (PCBs), chemicals that can build
up in the fatty tissue of fish, are found in seafood.
• Farmed fish pose additional health risks and environmental
concerns.
• Know where and how your fish is caught.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Vitamins
• Potent, essential, organic compounds
• Promote growth and help maintain life and health
• Two types
• Fat soluble—absorbed through intestinal tract with the
help of fats. A, D, E, and K vitamins are fat soluble.
• Water soluble—dissolve in water. B-complex vitamins
and vitamin C are water soluble.
• Few Americans suffer from vitamin deficiencies.
• Overusing them can lead to a toxic condition known as
hypervitaminosis.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Antioxidants
• Most common are vitamin C, vitamin E, and beta-carotene
• Free radicals damage or kill healthy cells.
• Antioxidants scavenge free radicals, slow their formation,
and repair oxidative stress damage.
• Carotenoids
• Lycopene (in tomatoes, papaya, pink grapefruit, and guava)
reduces the risk of cancer.
• Lutein (in green leafy vegetables, spinach, broccoli, kale, and
brussels sprouts) protects the eyes.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Folate
• A form of vitamin B that is needed for DNA production
in body cells
• Deficiency can result in spina bifida
• Dangers of taking too much folate include nerve
damage, immunodeficiency problems, anemia, fatigue,
headache, constipation, diarrhea, and weight loss.
Copyright © 2011 Pearson Education, Inc.
A Guide to Water-Soluble Vitamins
Copyright © 2011 Pearson Education, Inc.
A Guide to Water-Soluble Vitamins
Copyright © 2011 Pearson Education, Inc.
A Guide to Fat-Soluble Vitamins
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 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, and chloride
• Trace minerals are needed in small amounts
• Iron, zinc, manganese, copper, and iodine
• Excesses or deficiencies of trace minerals can cause
serious problems.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Sodium
• Necessary for regulation of blood and body fluids,
transmission of nerve impulses, heart activity, and
certain metabolic functions.
• Recommended consumption less than 1 teaspoon of
table salt per day
• Pickles, snack foods, processed cheeses, canned
soups, frozen dinners, breads, smoked meats, and
sausages contain large amounts.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Calcium
• Plays a vital role in building strong bones and teeth,
muscle contraction, blood clotting, nerve impulse
transmission, regulating heartbeat, and fluid balance
within cell
• Recommended amount 1,000 to 1,200 mg/day
• Milk, calcium-fortified orange juice, soy milk,
broccoli, cauliflower, peas, beans, nuts, and molasses
are good sources.
Copyright © 2011 Pearson Education, Inc.
Obtaining Essential Nutrients
 Iron
• The most common nutrient deficiency globally
• Women aged 19 to 50 need about 18 mg per day, and
men aged 19 to 50 need about 10 mg.
• Iron-deficiency anemia—body cells receive less
oxygen, and carbon dioxide wastes are removed less
efficiently
• Iron toxicity—ingesting too many iron containing
supplements
• Men who consume excess iron have a higher risk of
gallstones.
Copyright © 2011 Pearson Education, Inc.
A Guide to Major Minerals
Continued
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A Guide to Major Minerals
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A Guide to Trace Minerals
Copyright © 2011 Pearson Education, Inc.
Continued
A Guide to Trace Minerals
Copyright © 2011 Pearson Education, Inc.
Determining Your Nutritional Needs
 Reading Labels for Health
• Recommended Dietary Allowances (RDAs)
• Recommended Daily Intakes (DRIs)
• U.S. Recommended Dietary Allowances (USRDAs)
• Adequate Intake (AI)
• Tolerable Upper Intake Level (UL)
Copyright © 2011 Pearson Education, Inc.
Reading a Food Label
Copyright © 2011 Pearson Education, Inc.
ABC News Video: You Are What You Eat
| You Are What You Eat
Discussion Questions
1. Is posting calorie counts on menus helpful? What other dietary
information would help people make the healthiest choice?
2. Should more restaurants be required to follow this trend?
3. Is it up to a restaurant or a consumer to make people aware of
dietary information and healthy choices?
4. Are you surprised by some of the calorie counts?
5. Does seeing calorie counts affect your food choices?
Copyright © 2011 Pearson Education, Inc.
Determining Your Nutritional Needs
 Supplements: Research on the Daily Dose
• Dietary Supplements
• Products taken by mouth to supplement existing diets
• Includes vitamins, minerals, and herbs
• FDA does not evaluate supplements prior to their
marketing; companies are responsible for their own
monitoring
• A multivitamin added to a balanced diet will generally do
more good than harm.
• Probiotics—live microorganisms found in fermented
foods that optimize the bacterial environment in our
intestines
Copyright © 2011 Pearson Education, Inc.
Determining Your Nutritional Needs
 The 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
Copyright © 2011 Pearson Education, Inc.
MyPyramid Plan
Copyright © 2011 Pearson Education, Inc.
Determining Your Nutritional Needs
 Using the MyPyramid Plan
• Understanding serving sizes
• Discretionary calories
• Physical activity
• Eating nutrient-dense foods
Copyright © 2011 Pearson Education, Inc.
Serving Size Card
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Gender & Health
 Men and Women Have Different Needs
• Women have cyclical changes.
• During pregnancy and lactation, women’s nutritional
requirements increase substantially.
• During the menstrual cycle, many women report
significant food cravings.
• Men have more lean tissue (burn more calories).
• Men also tend to consume more red meat and less
fruits and vegetables than women do.
Copyright © 2011 Pearson Education, Inc.
Vegetarianism
 Reasons for Pursuing a Vegetarian Lifestyle
• Animal welfare
• Improving health
• Environmental concerns
• Natural approaches to wellness
• Food safety
• Weight loss
• Weight maintenance
Copyright © 2011 Pearson Education, Inc.
Vegetarianism
 Types of Vegetarian Diets
• Vegan
• Lacto-vegetarian
• Ovo-vegetarian
• Lacto-ovo-vegetarian
• Pesco-vegetarian
• Semivegetarian
 The MyPyramid Plan is adaptable for a vegetarian
diet
Copyright © 2011 Pearson Education, Inc.
Vegetarianism
 Benefits to a Balanced Vegetarian Diet
• May weigh less.
• Have better cholesterol levels
• Have fewer problems with constipation and diarrhea
• Have lower risk of heart disease
• Have reduced risk of some cancers, particularly colon
cancer
• Have reduced risk of kidney disease
Copyright © 2011 Pearson Education, Inc.
Nutritional Needs for People with Different Energy
Requirements
Copyright © 2011 Pearson Education, Inc.
Improved Eating for the College Student
 When Time and Money Are Short
• Ask for nutritional analyses of items.
• Order salads, but be careful about what you add to them.
• Avoid lard-based or other saturated-fat products and
trans fats.
• Avoid giant sized portions, and refrain from ordering
extras
• Limit beverages and foods high in added sugars.
• At least once per week, add a vegetable-based meat
substitute into your fast-food choices.
Copyright © 2011 Pearson Education, Inc.
Food Safety: A Growing Concern
 Foodborne Illnesses
• Foodborne pathogens sicken over 76 million people and
cause 400,000 hospitalizations and 5,000 deaths per
year.
• Signs
• Cramping
• Nausea
• Vomiting
• Diarrhea
• Most of the time, symptoms occur 5 to 8 hours after
eating.
Copyright © 2011 Pearson Education, Inc.
Budget Nutrition Tips
Copyright © 2011 Pearson Education, Inc.
Food Safety: A Growing Concern
 Contributing Factors to the Increase in Foodborne
Illnesses
• Globalization of food supply
• Introduction of pathogens to new geographic regions
• Exposure to unfamiliar foodborne hazards
• Changes in microbial populations
• Increased susceptibility of varying populations
• Insufficient education about food safety
Copyright © 2011 Pearson Education, Inc.
Food Safety: A Growing Concern
 Avoiding Risks in the 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.
• Use a meat thermometer.
• Never thaw foods at room temperature.
Copyright © 2011 Pearson Education, Inc.
Food Safety: A Growing Concern
 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 shelf life and prevents
spread of microorganisms
• Reduces need for toxic chemicals
currently used
• Marked with the radura logo
Copyright © 2011 Pearson Education, Inc.
U.S. FDA label
Food Safety: A Growing Concern
 Food Additives
• Substances added to food to reduce the risk of
foodborne illness, that prevent spoilage, enhance
nutrient value, and enhance the look and taste of
foods
• Examples of common additives include
• Antimicrobial agents
• Antioxidants
• Artificial color, nutrient additives, and flavor
enhancers such as MSG
• Sulfites
Copyright © 2011 Pearson Education, Inc.
Food Safety: A Growing Concern
 Food Allergy or Food Intolerance?
• Food Allergies
• Abnormal response to a food triggered by the immune
system
• Symptoms include rapid breathing or wheezing, hives,
rash, eczema, runny nose, facial swelling, or respiratory
problems (anaphylactic reaction)
• In 2004, Congress passed the Food Allergen Labeling and
Consumer Protection Act (FALCPA), which requires
food manufacturers to clearly label foods containing
ingredients that are common allergens.
Copyright © 2011 Pearson Education, Inc.
Food Safety: A Growing Concern
 Food Allergy or Food Intolerance?
• Food Intolerances
• Less dramatic reaction than food allergies
• Not the result of immune system response
• Generally shows as gastric upset
• Lactose intolerance is common and also happens in
response to food additives (MSG, sulfites, gluten)
• May have psychological triggers
Copyright © 2011 Pearson Education, Inc.
Food Safety: A Growing Concern
 Is Organic for You?
• Food developed, grown, or
raised without use of synthetic
pesticides, chemicals, or
hormones
• As of 2010, organic food sales
estimated to be about $23.8
billion
• Foods need to meet criteria set
by USDA to be certified
organic
• Locavores—people who eat
only food grown or produced
locally
Copyright © 2011 Pearson Education, Inc.
USDA label for certified organic foods