Transcript 9 Eating for Healthier You

Chapter 9 Lecture
Health: The Basics
Tenth Edition
Eating for a
Healthier You
Healthy Eating: An Overview
• Hunger: The physiological impulse to seek food, prompted
by the lack or shortage of basic foods needed to provide the
energy and nutrients needed to support health
• Nutrients: The constituents of food that sustain humans
physiologically: proteins, carbohydrates, fats, vitamins,
minerals, and water
– MACROnutrients- Nutrients we need in large amounts- Carbs, Proteins, Fats
– MICROnutrients- Nutrients we need in small amounts- Vitamins, Minerals
• Appetite: The desire to eat normally accompanies hunger
but is more psychological than physiological
• Nutrition: The science that investigates the relationship
between physiological function and the essential elements of
foods eaten
• Digestive Process: The process by which the body breaks
down foods and either absorbs or excretes them
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Essential Nutrients for Health
• Calorie: A unit of measure that indicates
the amount of energy obtained from a
particular food
• We get energy from the calorie containing
food we eat
– Fat is the most concentrated source of energy and
provides 9 calories per gram.
– Carbohydrates and proteins contribute 4 calories per
gram
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6 Essential Nutrients for Health
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Water
Proteins
Carbohydrates
Fats
Vitamins
Minerals
Food provides the chemicals we need for
activity and body maintenance.
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Water: A Crucial Nutrient
• Humans can survive longer without food than
without water.
• Dehydration can cause serious problems
within hours, and death within a few days.
• The body consists of 50–60% water by
weight.
• Water is obtained through foods and
beverages that are consumed.
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Proteins
• After water, proteins are the most abundant substances
in the body.
– Used to repair bone, muscle, skin and blood cells, and are key
elements of antibodies.
– Proteins help transport iron, oxygen, and nutrients to all body
cells.
• Structure and Sources of Proteins
– Amino acids are the building blocks of proteins; 9 of the 20 are
essential because they must be obtained from food; the other 11
can be produced by the body.
– Dietary protein that supplies all 9 essential amino acids is known
as complete (high-quality) protein.
– Proteins from plant sources lack one or more amino acids and
are known as incomplete proteins.
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How Much Protein Do I Need?
• The average American consumes more than 78
grams of protein daily, mostly from animal
sources.
• Recommended intake is only 0.8 grams protein
per kilogram of body weight.
– Divide your body weight by 2.2 to get your weight in
kilograms
– Then multiply by 0.8
– The typical recommendation for a 2,000 cal diet- 10%
to 35% of calories should come from lean protein
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Carbohydrates
• Are the best fuel source and provide energy
quickly and efficiently.
• Carbohydrates supply energy needed to
sustain normal daily activity. They are
metabolized faster and more efficiently than
protein.
• Carbohydrates are converted to glucose.
• They play an important role in the functioning
of the internal organs, the nervous system,
and muscles and are the best fuel for
endurance athletes.
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Forms of Carbohydrates
• Simple Carbohydrates
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Glucose (monosaccharide)- simple sugars
Fructose (monosaccharide)—fruit sugar
Sucrose (disaccharide)—granulated table sugar
Lactose (disaccharide)—milk sugar- the only simple sugar that
comes from animals
• Maltose (disaccharide)—malt sugar
• Complex Carbohydrates
(polysaccharides)
• Starches—grains, cereals, and vegetables
– Stored in the body as glycogen
• Fiber—"bulk" or "roughage"
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What Carbohydrates Should I Eat? Which
Should I Avoid?
• Whole grains and high-fiber diets can
protect against obesity, colon and rectal
cancers, heart disease, constipation, and
perhaps type II diabetes.
• Choose foods such as brown rice, wheat,
bran, and whole grain breads and cereals.
• Increase fiber intake to 20–35 grams per
day.
• Eat fewer refined carbohydrates.
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Fats (Lipids)
• Misunderstood but a vital group of basic nutrients that do the
following:
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Maintain healthy skin
Insulate body organs
Maintain body temperature
Promote healthy cell function
Carry fat-soluble vitamins A, D, E, and K
Supply a concentrated form of energy
• Triglycerides make up 95% of total body fat.
– When we consume too many calories from any source, the liver
converts the excess into triglycerides, which are stored throughout our
bodies.
• Cholesterol makes up 5% 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.
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Fat and Trans Fatty Acid
• 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.
• Avoiding Trans Fatty Acid
– Created by process of making liquid oil into a solid.
– Increases 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 deep-fried foods.
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Is More Fat Ever Better?
• Moderation is key. No more than 7 to 10%
of your total calories should come from
saturated fat and no more than 35%
should come from all forms of fat.
– Eat fatty fish.
– Use healthier oils (including olive oil).
– Eat green, leafy vegetables.
– Eat walnuts and use walnut oil.
– Eat ground flaxseed.
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Essential Nutrients for Health
• To Reduce Your Overall Intake of Less
Healthy Fats
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Read food labels.
Use olive oil for cooking.
Chill soups and stews and scrape off any fat that hardens.
Hold the creams and sauces.
Fill up on fruits and vegetables.
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.
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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
and tend to store in the body. Toxic accumulations
may cause cirrhosis-like symptoms.
– Water soluble—dissolve in water. B-complex
vitamins and vitamin C are water soluble. These are
generally excreted and cause few toxicity problems.
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Antioxidants
• Antioxidants
– Often in functional foods
– Most common are vitamin C, vitamin E, and betacarotene.
– Free radicals damage or kill healthy cells.
– Antioxidants scavenge free radicals, slow their
formation, and repair oxidative stress damage.
• Vitamin D
– Formed when skin is exposed to the sun.
– Improves bone strength, helps fight infections, lowers
blood pressure.
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Minerals
• Inorganic, indestructible elements that aid the
body
– Vitamins cannot be absorbed without minerals
• Major minerals 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.
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Sodium and Calcium
• 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
• 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.
– Most Americans do not consume the recommended
amount of 1,000 to 1,200 mg/day.
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Iron
• The most common nutrient deficiency globally
• Women aged 19 to 50 need about 18 mg per
day.
• 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 ironcontaining supplements
• Men who consume excess iron have a higher
risk of gallstones.
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DRIs: Recommended Intakes for Nutrients
• Dietary Reference Intake (DRIs): a list of 26 nutrients
essential to maintaining health
• Recommended Daily Allowances (RDAs): the reference
standard for intake levels necessary to meet the nutritional
needs of 97–98% of healthy individuals
• Adequate Intake (AI): the recommended average daily
nutrient intake level when there is not enough research to
determine the full RDA
• Tolerable Upper Intake Level (UL): the highest amount of a
nutrient that an individual can consume daily without risk of
adverse effects
• Acceptable Macronutrient Distribution Range (AMDR): the
range of intakes for carbohydrates, fat, and protein associated
with a reduced risk of chronic disease, that provides adequate
levels of essential nutrients
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How Can I Eat More Healthfully?
• What Is a Healthful Diet?
– A healthful diet should be
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Adequate
Moderate
Balanced
Varied
Nutrient dense
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Dietary Guidelines for Americans, 2010
• MyPlate plan
• Balance calories
– Enjoy your food, but eat less.
– Avoid oversized portion.
• Foods to increase
– Make half your plate fruits and vegetables.
– Make at least half your grains whole.
– Switch to fat-free or 1% milk.
• Foods to reduce
– Compare sodium in foods such as soup, bread, and
frozen meals – choose foods with lower numbers.
– Drink water instead of sugary drinks.
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MyPlate Plan
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How Can I Eat More Healthfully? (cont.)
• Understand serving sizes
• Eat nutrient-dense foods
• Reduce empty calorie foods
– Cakes, cookies, pastries, and donuts
– Sodas, energy drinks, sports drinks, and fruit
drinks
– Cheese
– Pizza
– Ice Cream
• Physical activity
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Serving Size Card
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Read the Labels
• % Daily Value (%DV)
• Other claims include
– Nutrient content claims
– Structure and function claims
– Dietary guidance claims
– Qualified health claims
– Health claims
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Reading a Food Label
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Vegetarianism: A Healthy Diet?
• Strict vegetarians, or vegans, avoid all food of
animal origin.
• Lacto-vegetarians eat dairy products but avoid flesh
foods and eggs.
• Ovo-vegetarians add eggs to the vegan diet.
• Lacto-ovo vegetarians eat both dairy products and
eggs.
• Pesco-vegetarians eat fish, dairy products, and
eggs.
• With proper information and food choices,
vegetarianism provides a superb alternative to meatbased cuisine.
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Supplements: Research on the Daily Dose
• Dietary Supplements
– Products taken by mouth to supplement
existing diets
– Include 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.
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Eating Well in College
• If you must eat fast food
– 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.
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ABC News Video: You Are What You Eat
Discussion Questions
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Do you think it is a good idea for restaurants to post
calorie content for the food on their menus? Would
knowing the calorie content of a particular food keep
you from ordering it?
What are the goals of including calorie content of foods
on restaurant menus?
Why are "healthy" options in danger of being removed
from restaurant menus?
How can restaurants respond responsibly to
progressive laws such as the one requiring the posting
of calorie information on menus?
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Eating Well in College (cont.)
• In the dining hall try this
– Choose lean meats, grilled chicken, fish or vegetable
dishes. Avoid fried foods.
– Hit the salad bar and pick leafy greens, beans, tuna or
tofu, and avocados or nuts.
– Choose baked potatoes with salsa, or add grilled chicken
to your salad.
– At the made-to-order section, hold the butter, mayonnaise,
sour cream or cheese, or cream-based sauces.
– Avoid seconds, and pass on high-calorie, low-nutrient
sweets.
– Ask the food services manager about providing additional
healthy options.
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