Download Nutrition Unit

Nutrition Unit
Health 2
Why Nutrition Matters
Nutrition – The process by which your
body takes in and uses food
The food you eat plays a significant role in
your total health
Your body relies on food to provide it with
nutrients – substances in food that your
body needs to grow, to repair itself, and to
supply you with energy
What is a CALORIE???
The energy your body receives from food is
measured in calories
A calorie is a unit of heat used to measure
the energy your body uses and the energy
it receives from food
The calories in the food you eat provide the
energy your body needs for daily/lifelong
activities
What Influences your food choices?
Choosing the right foods in the right amounts
will give your body the nutrients it needs for
healthy growth and development
People eat for 2 reasons: hunger and appetite
Hunger – is the natural physical drive to eat
prompted by the body’s need for food
When you are hungry, you may feel lightheaded or tired
Appetite – is the psychological desire for food
Example – the smell of cookies baking tempts you to eat
them, even if you are full
Foods and Emotions
 Sometimes, people eat in response to an emotional
need
 Stressed
 Frustrated
 Lonely or sad
• Can lead to your body not getting all the nutrients it needs because of
loss of appetite
 People may snack out of boredom or use food as a
reward
 Can lead to weight gain since you are eating when your body
doesn’t need food
 Some people “mindless eat” – which is snacking
continuously while absorbed in another activity
Food and Your Environment
The people and things around you affect what
you choose to eat. Environmental influences
include :
Family and Culture
Friends
Time and Money
Advertising
Group Discussion – Why do advertisers want to
influence your food choices?
Journal Writing – Write a paragraph describing why it’s
important for schools to offer students healthful food
choices
Review
Name 3 health problems that good
nutrition can help you avoid?
What is the difference between hunger
and appetite
Identify 2 emotions that influence eating
when someone isn’t hungry
Giving Your Body What It Needs
Everything you eat contains nutrients.
Nutrients provide specific roles in
maintaining your body functions
Your body uses nutrients in many ways:
As an energy source
To heal, and build and repair tissue
To sustain growth
To help transport oxygen to cells
To regulate body functions
6 Types of Nutrients
 1. Carbohydrates
 2. Proteins
 3. Fats
Above provide energy
 4. Vitamins
 5. Minerals
 6. Water
Above perform a variety of other functions
***Each gram of carbohydrate or protein provide 4
calories of energy
***Each gram of fat provides 9 calories
Carbohydrates
 Starches and sugars found in foods, which
provide your body’s main source of energy
 Most nutritionists recommend getting 45% to
65% of your daily calories from carbs.
 3 types of Carbohydrates:
Simple – sugars such as fructose (found in fruits) and
lactose (found in milk)
Complex – starches, long chains of sugars linked
together (grains bread, pasta, beans and potatoes
Fiber – a tough complex carb. that the body cannot
digest (fruits, veggies, whole grains, and products made
from whole grains, nuts, seeds, and legumes
Role of Carbohydrates
The body uses carbs by breaking them
down into their simplest forms
Most carbs you consume are turned into
simple sugar called glucose
Glucose can be stored in your body’s
tissue and used later during periods of
intense activity
Benefits of Fiber
Although the body cannot digest fiber, it
plays an important role by aiding in
digestion and reducing the risk of disease
Experts recommend eating 26 grams of
total fiber daily for teen girls (14-18) and
38 grams for teen boys
Proteins
 Are nutrients the body uses to build and
maintain its cells and tissues.
 Made up of chemicals called amino acids
 The body uses about 20 amino acids that are
found in foods
 You produce all but 9…these are called essential amino
acids because your body must get them from food
 Foods high in protein
 Meat, eggs, soy, grains, nuts, seeds, legumes and dairy
products
The Role Of Proteins
Protein is the basic building material of all
your body cells
Muscles, bones, skin, and internal organs
are all constructed of protein
Helps your body grow during childhood
and adolescence
The protein hemoglobin in your red blood
cells carries oxygen to all your body cells
Proteins may also function as hormones
Fats
Most of what you hear about fats is how to
avoid them…
Does this mean you shouldn’t eat any fat
at all?
No. Your body needs a certain amount of fat to
function properly. You can, however, choose
healthier fats
Types Of Fat
 Unsaturated Fats – vegetable oils, nuts, and
seeds tend to contain larger amounts of
unsaturated fats
 Saturated Fats – found mostly in animal-based
foods (meat and dairy)
 Trans Fat – These fats are formed by a process
called hydrogenation (causes veg. oil to harden)
 Found in margarine, many snack foods, and packaged
baked goods
 Can raise your total blood cholesterol level, which
increases your risk for heart disease
The Role Of Fats
Fats provide a concentrated form of
energy
Very important in brain development,
blood clotting, and controlling inflammation
Also help maintaining healthy skin and hair
Also absorbs and transports fat-soluble
vitamins (A,D, E and K) through the
bloodstream
Roles Of Fat Cont.
 Calories from fats that your body does not use
are stored as body fat
 Body fat provides insulation for the body
 Too much body fat can lead to type 2 diabetes
and cardiovascular disease
 Consuming saturated fats can increase levels of
cholesterol – a waxy, fatlike substance in your
blood
 Excess cholesterol can build up in your arteries and cause
heart disease (heart attack, stroke, etc.)
Other Nutrients
Vitamins – are compounds found in food that
help regulate many body processes
Water Soluble Vitamins – dissolve in water and pass easily
into bloodstream…unused are removed by kidneys
(vitamins C, folic acid, and B vitamins)
Fat Soluble Vitamins – Stored in body fat for later use
(vitamins A, D, E, and K)
Minerals - are elements found in food that are
used by the body
Body doesn’t produce minerals – you must get them from
food
Calcium – very important mineral – promotes bone health –
can prevent osteoporosis
Nutrients Cont.
 Water – is essential for most body functions
 Moving food through the digestive system
 Digesting carbs. and protein
 Transporting nutrients and removing wastes
 Storing and releasing heat
 Cooling the body through perspiration
 Cushioning the eyes, brain, and spinal cord
 Lubricating the joints
 Teen girls need about 9 cups of fluids a day
 Teen boys need about 13 cups of fluids a day
 Drinking water prevents dehydration. If you feel thirsty –
you have waited too long to take in fluids
Healthy Food Guidelines
No time for breakfast?
Ever since she started high school, Tina never seems
to have enough time for breakfast. Homework keeps
her up late, so when she wakes up the next morning,
she barely has time to get dressed and catch the bus.
Most mornings in class, she feels weak and sluggish,
and by lunchtime she’s ravenous. Tina wants to find
the time to eat breakfast so she has more energy
throughout the day
Pretend you are Tina. In a paragraph, write out
a plan to fit breakfast into your busy schedule
Guidelines for Eating Right and Active
Living
The Dietary Guidelines for Americans are a set
of recommendations about smart eating and
physical activity for all Americans
Developed by the U.S. Department of
Agriculture and the Department of Health and
Human Services
They provide science-based advice for healthful
eating and information on the importance of
active living
Can be summed up in 3 key guidelines
• Make smart choices from every food group
• Find your balance between food and activity
• Get the most nutrition out of your choices
Making Smart Choices
Choosing a variety of foods from each
food group will provide all the nutrients
your body needs.
5 major food groups
Grains
Vegetables
Fruits
Milk
Meats and Beans
What’s On Your Plate???
Show the size of foods that should take up
your plate space…
Now lets take a look at what “real” portion
sizes look like…
http://www.youtube.com/watch?v=yDbocZ
438f0
Hungry after school???
Try these sensible snacks:
Fresh fruit
Cut-up veggies, such as carrots and celery
String cheese
Unsalted nuts
Air-popped popcorn
Fat-free yogurt
Eating Out…
And eating right –
Making healthful food choices is just as
important when you eat away from home,
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Watch portion sizes
Pay attention to how foods are prepared
Add fresh vegetables and fruits
Go easy on toppings
Don’t drink your calories
Nutrition Labels and Food Safety
 Whenever you buy a package of food, it has a
label that tells you about the nutritional value of
what’s inside.
 Also lists the ingredients that were used to
prepare the food
 Food labels also list
 The name of the product
 The amount of food in the package
 The name and address of the company that makes,
packages, and distributes the product
 The Nutrition Facts panel, which provides information
about the nutrients found in the food
Ingredient List
Appears on a label in descending order by
weights
Food additives – substances added to a
food to produce a desired effect
• May be used to keep food fresh for a longer period of
time
• To boost its nutrient content
• To improve its taste, texture, or appearance
***2 major food additives – aspartame and
olestra
Labels and nutritional claims
 Free – the food contains none, or an insignificant amount
of a given component
 Low – Low fat foods for example must have 3 grams of
fat or less
 Light – Must contain 1/3 fewer calories, ½ the fat, or ½
the sodium of the original version
 Reduced – The food contains 25% fewer calories or 25%
less of a given nutrient that its original version
 High – Food provides at least 20% of the daily values for
a vitamin, mineral, protein or fiber
 Good Source Of – Food provides 10-19% of the daily
values for a vitamin, mineral, protein or fiber
 Healthy – must be low in fat and saturated fat and
contain limited amounts
Organic Food Labels
USDA Organic
Foods labeled with organic are produced
without the use of certain agricultural
chemicals such as, synthetic fertilizers or
pesticides
Also cannot contain genetically modified
ingredients or be subjected to certain
types of radiation
Food Safety
Handling food carefully can help you avoid
foodbourne illnesses and other hazards
Foodbourne illness – AKA food poisoning
Food can contain pathogens or disease-causing
organisms
Most common are Salmonella, E. Coli and a group of
viruses known as the Norwalk and Norwalk-like
viruses
Common symptoms include cramps, diarrhea,
nausea, vomiting and fever
Keeping Food Safe To Eat
Pasteurization – is treating a substance
with heat to kill or slow the growth of
pathogens
Cross-contamination – the spreading of
pathogens from one food to another
Separate foods that carry pathogens (raw meat,
poultry, seafood, and eggs)
Cook to a high enough temperature to kill
pathogens
Chill – refrigeration slows the growth of harmful
bacteria
Food Sensitivities
 Can make some foods dangerous to eat
 Food Allergy – is a condition in which the body’s
immune system reacts to substances in some
foods
 Milk, eggs, peanuts, tree nuts, soybeans, wheat, fish, and
shellfish
 The symptoms of allergies vary from mild to lifethreatening
 Skin irritations (rashes, hives, or itching)
 Gastrointestinal Symptoms (nausea, vomiting, or diarrhea)
 Anaphylaxis – most dangerous symptom – throat swells
up and the heart has difficulty pumping
Food Sensitivities Cont.
Food intolerance – a negative reaction to
food that doesn’t involve the immune
system (more common than a food
allergy)
Lactose Intolerance – most common – occurs when a
person’s body doesn’t produce enough of the
enzyme needed to digest lactose, the sugar found in
milk
 May experience gas, bloating, and abdominal pain
Your Energy Balance
Metabolism – the process by which the
body breaks down substance and gets
from food (converts the food you eat into
fuel)
It takes about 3,500 calories to equal 1
pound of body fat
Thus, if you consume 500 fewer calories than you
use every day, you will lose 1 pound per week
Body Mass Index (BMI)
BMI – a measure of body weight relative to
height
Overweight – heavier than the standard weight range
for your height
Obese – having an excess of body fat
Underweight – below the standard weight range for
your height
Healthful Way to Lost Weight
 Choose nutrient-dense foods – fruits, veggies, and
whole grains supply nutrients with fewer calories
 Watch portion sizes – stick to recommended portion
sizes for each major food group
 Eat fewer food that are high in fats and added sugars
– these add calories without many nutrients
 Enjoy your favorite foods in moderation
 Be active
 Tone your muscles – muscle tissue takes more
calories to maintain than fat
 Stay hydrated
Healthful Way to Gain Weight
 Select foods from the 5 major food groups that
are higher in calories
 Choose higher-calorie, nutrient-rich foods (nuts,
dried fruits, cheese, avocados)
 Eat nutritious snacks – enjoy more often to
increase daily calorie intake
 Get regular physical activity – since you are
increasing your calorie intake, exercise will
make sure you gain muscle rather than fat