Chapter of Biology class of Nutrition and sources of energy

1. FOOD AND ENERGY
FACT OR FICTION?
a. Athletes need more proteins in their diets.
b. The only salt in food is the one you add to
it.
c. As a part of a healthy diet, everyone
should take vitamin supplements.
d. You can go without water for longer than
you can go without food.

2. WHY IS FOOD NEEDED?
• Remember homeostasis?
• FOOD PROVIDES ENERGY
THAT IS NEEDED AND THE
MATERIALS NECESSARY TO
GROW AND REPAIR
TISSUES.
• NUTRIENTS: Substances in food that
provide the raw materials and energy
the body needs to carry out all the
essential processes.

3. NUTRIENTS
• SIX KINDS: • To measure energy, the
– Carbohydrates unit is calorie.
– Fats • 1 cal = the amount of
– Proteins energy necessary to
– Vitamins raise 1oC 1g of water.
– Minerals
• 1 Calorie = 1000 cal
– Water
• The more calories, the
more energy.

4. CARBOHYDRATES (CHO’s)
• Composed of Carbon, Hydrogen and
Oxygen
• Major source of energy:
– 1g CHO’s = 4000 calories
• Recommended ingestion: 50-60% of
total Calories needed as CHO’s
• Classified in: Simple and Complex.

7. FATS
• High energy nutrients made of
Carbon, Hydrogen and Oxygen; but has
more than twice the energy of
carbohydrates.
• Classified as:
– Unsaturated: Liquid at room temperature.
– Saturated: Solid at room temperature.
• No more than 30% of the Calories in your
diet should come from fats.

9. PROTEINS
• Nutrients that contain Nitrogen as
well as Carbon, Hydrogen and
Oxygen. These are needed for
tissue growth and repair.
• Found in meat, poultry, fish, lentils
and dairy products.
• 12% of your diet should come from
proteins.
• Made of Amino Acids (AA’s): 20
different make up all proteins.
• Essential AA’s: Comes only from
food.
• Complete/Incomplete: Depend on
the number of AA’s in them.

10. NEEDED IN SMALL AMOUNTS…
VITAMINS MINERALS
• Act as helper molecules • Nutrients NOT made by
in chemical reactions living things.
inside the body. • Found in plants or animals
• Water-soluble: You need that eat plants.
to ingest them daily • Examples:
• Fat soluble: Can be – Calcium Chlorine
stored in fatty tissue. – Fluorine Iodine
– Potassium Iron
– Magnesium Phosphorus
– Sodium

14. WATER
• Makes up about 65-
70% of our body
weight.
• Needed for:
– Digestion
– Body fluids DRINK 2 LITERS A DAY
(saliva, blood, sweat
)
– Cell transport, etc.

15. THE FOOD GUIDE PYRAMID
• Classifies food into six groups and indicates how many
servings from each group should be eaten every day.

16. FOOD LABELS
• Tells you in
numbers, the
nutrient content
of a food so you
can evaluate
and compare.