Transcript Nutrition – 2 categories

Nutrition
• Nutrition – 2 categories –
– Pure science – looks at how the body uses
nutrients
– Social Science – relationship between food
and human behavior and the environment.
Why do you eat?
There are 3 main reasons, why we eat.
☻Physical Health
☻Environment
☻Emotions
Physical Health
• Food along with air and water is one of life’s
basic needs.
• Eating the right kinds of food
– (fruits, veggies, carb’s, protein, calcium, water)
• Help you:
– To stay alive
– To stay fit
– To be active
• Many of the leading causes of death (cancer,
stroke, diabetes, heart attack, etc.) are linked to
food in some way.
Environment
– Culture- picnics, baseball games, holidays,
birthday parties- Food choices reflect the
culture you live in, ethnic background,
religious beliefs, teen culture
– Family & social relationships- children
pattern their food habits after their role
models, what, when, like, dislike,
• As you get older friends may influence your food
choices – new foods at their homes,
• Food is usually present at social gatherings, can
be given as gifts etc.
Environment
– Media messages- ads are everywhere. TV,
magazines, billboards
• Which foods have you bought as a result of an ad?
Ads may try to persuade you. Which foods do you
see being advertised? Fruits, veggies, fatty foods
etc..
– Life-style- Cost, convenience, taste, nutrition,
food safety influence food shopping. Time &
Money.
Emotions
• Think about your eating habits. Are you
eating because you are hungry? Because
you are bored, lonely, angry, excited,
nervous? Or don’t you eat when you are
experiencing the above emotions?
Nutrition Throughout Your Life
At every stage in life, good nutrition is
essential for health.
Before you were born
- Proper nutrition is essential for a healthy
baby to be born
- 10 months
- fast growth
Infant
- Proper Nutrition is essential for proper
growth
- 0-2yrs.
- Fast growth
Adolescence
- Fastest and most growth you will
experience.
- Many teens skip meals or substitute highfat or sugary foods for more nutritious
choices.
Why??
- Nutrients- substances in food that the
body needs to function properly.
- i.e. growing, repairing itself, supply of energy
Recommended Dietary
Allowances (RDAs)
Recommended intakes of nutrients that
meet the needs of almost all healthy
people of similar age and gender. These
are established by the Food and Nutrition
Board of the National Academy of
Sciences.
These nutrients can be grouped
into six main categories
1. Carbohydrates
2. Fats
3. Proteins
4. Vitamins
5. Minerals
6. Water
Note: Each has a unique function in the normal
growth and functioning of the body. No one food
provides all the nutrients your body needs.
Carbohydrates
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Carbohydrates- Provide energy- found
mainly in plant sources of food
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RDA for 2000 calorie diet
~55-65% of calories come from carbohydrates mainly
complex carbohydrates
~130 grams
~Fruit- 2 cups, vegetables 2 ½ cups, grains 6 oz. (6
servings)
Fiber RDA- 21-38 grams
Eating enough carbohydrates allow protein to be used
for building and repairing the body. When protein is
used for energy, it cannot be used for other purposes.
Sugar RDA- no more than 10% of total calories, or for
2000 calorie diet 200 calories, or 50 grams
There are Two Forms of
Carbohydrates
• Simple carbohydrates.
• Complex carbohydrates
Simple carbohydrates
• a. Fruits, some vegetables and milk –
natural sugar
• b. Table sugar, syrups and molasses
(processed sugars) added to many foods
including sweet desserts, candies and soft
drinks
Complex carbohydrates
• a. Starches- i.e.
• b. Fiber – i.e.
helps move waste through your
digestive system and helps prevent
constipation, appendicitis and other
intestinal problems.
Fats- (Lipids)- fatty substances that
do not dissolve in water
RDA based on 2000 calorie diet
• ~No more than 30% of calories from fat
• ~25-30 grams
• ~Servings- use sparingly or no more than
290 calories per day
Role of fat
– carry fat-soluble vitamins A,D,E, and K into your
blood without fats our bodies could not use these
nutrients.
– provides essential fatty acids i.e. linoleic acid
essential for growth and healthy skin.
– Add flavor.
– Satisfy hunger because they take longer to digest.
– Stored energy – it accumulates when people.
consume excess calories from any source.
– Cushions your vital organs, protecting them from
injury.
– Insulates your body from heat and cold.
Saturated Fats
• animal fats (beef, pork, egg yolks, dairy
foods) (chicken and fish are lower) and
some vegetable oils (palm, coconut),
butter, chocolate, cream soups,
croissants, doughnuts
• Usually solid or semisolid at room
temperature
Unsaturated Fats
• - vegetable fats (soybean, corn,
cottonseed, olive oils)
• Usually liquids or oils at room temperature
Trans fat
• Specific type of fat formed when liquid oils
are made into solid fats like shortening
and hard margarine. They raise
cholesterol which increases your risk of
heart disease. Found in crackers,
candies, cookies, snack food, fried food
and baked goods.
Cholesterol
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fatlike substance. Our liver can make the cholesterol it
needs therefore it is not considered a nutrient.
Cholesterol is essential to each cell membrane in the
human body. The body uses cholesterol to produce
vitamin D, certain hormones and the protective sheath
around nerve fibers. It also aids in digestion. However
in excess it can accumulate on the inner walls of the
arteries, causing health problems like heart attack and
stroke.
• 2 Types- no more than 300 mg is recommended
• Dietary cholesterol• Serum cholesterol-
Proteins- vital part of every body cell
• i.e. muscle, bone, connective tissue, teeth,
skin, blood & vital organs- all contain
protein
Proteins• RDA based on 2000 calorie diet
• 10-35% of total calories
• 51 grams for women, 64 grams for males
• Servings 5 ½ ozs. of meat and beans and
3 cups of milk (dairy products)
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Athlete recommendation
125 lb. athlete 63-94 grams
150 lb. athlete 75-113 grams
200 lb. athlete 100-150 grams
amino acids
• There are 20 different amino acids-our
body can make all but 9 – we need to get
those from food
• If you take in too many proteins the excess
will be stored as fat
Functions
• Proteins build all body tissues during periods of
growth for instance, infancy, childhood,
adolescence and pregnancy.
• Proteins maintain all body tissues during
periods of growth
• Proteins repair or replace damaged or worn out
cells during the rest of our lives
• If you don’t get enough carbohydrates and fats,
protein can be used for energy, but then it isn’t
building and repairing body tissues
Sources of Protein
• Animal sources ~fish, meat, poultry, eggs,
milk, cheese, yogurt
• Plant sources ~Legumes (beans), seeds,
nuts, lentils, tofu, many green vegetables
Vitamins
• Micronutrients because they are needed in
small amounts
• Functions:
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Help regulate many vital body
processes
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Do not supply calories
2 Types
Water soluble- dissolve in water
Any excess is excreted in urine
Pass easily into blood in the process of digestion
Since no reserves your body needs foods with these
vitamins everyday
(Vitamin C, Vitamin B1, B2, B6, B12)
Fat soluble- absorbed and transported by fat
Any excess is stored in the body
Too many can be toxic.
(Vitamin A,Vitamin E, Vitamin K)
Minerals
• Micronutrients the body can’t manufacture
• Help regulate many body functions
• Examples:
Calcium – building materials of bone and teeth, heart
muscle contraction (dairy, leafy veggies)
Iron – cell metabolism, rigidity to bones and teeth
(peas, beans, milk, liver, meat, cottage cheese, broccoli)
Potassium – controls acid-base and liquid balances
(bananas, oranges, prunes, meats)
Sodium – fluid balance (table salt, milk, meat, fish,
poultry)
Recommended intake of sodium: 1500-2400 mg
Minerals
• Females need more iron (menstruation)
and calcium (osteoporosis) than men
6. Water- most essential nutrient.
- Only oxygen is more important
- Our body’s are 2/3 water (60%)
Functions of water:
• Water carries nutrients to and transports wastes
from your cells
• Lubricates your joints and mucous membranes
• Enables you to swallow and digest food
• Absorbs nutrients
• Eliminates wastes
• Perspiration – helps cool body down
Recommended fluid intake:
Water, milk, juice.
– Requirements are different for everyone- varies with climate,
exercise, individual differences in perspiration
– Thirst is best indicator however a rule of thumb might be
– 1 oz / 3 lbs. of body weight
– You can also get water from foods you eat
i.e. celery
95%, watermelon 92%, broccoli 91%, potato 71%, cheddar
cheese 37%, mixed nuts 2%
• Water contains essential minerals
– Taste varies because of where it is coming from. Different rocks
and soil that it passes through. Consumer report – NYC
municipal water tastier than most bottled waters.