Transcript TPJ 3C1 Nutrition - the six nutrients

Nutrition
What is nutrition?
• the science of how the foods you
eat affect your body
What are nutrients?
• substances that nourish your
body
• Six categories of nutrients:
• Carbohydrates
• Proteins
• Fats
• Vitamins
• Minerals
• Water
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Carbohydrates
Carbohydrates
• function: the body’s main source of energy
• two categories: simple and complex
Simple Carbohydrates
• composed of one or two sugar units
• foods with LOTS of sugar: oranges and milk contain
natural sugars; cookies and candy are high in added
sugar
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Carbohydrates
Complex Carbohydrates
• starches that are composed of many
sugar units linked together
• your body breaks down starches into
smaller sugar units that are used for
energy
• foods with LOTS of starch:
rice, beans, potatoes
• many foods high in starches also
supply fiber (helps your digestive tract
work properly and may help protect
against heart disease and cancer)
Proteins
Proteins
• Structure: Proteins are made
from many amino acids
connected together in
different arrangements
• Function: help your body
grow, repair itself, and fight
disease
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• 9 of the 20 amino acids are called essential amino acids
because you must obtain them from the foods you eat
since your body cannot make them.
Proteins
Complete proteins:
•
foods containing all the essential amino acids
Examples: fish, meat, eggs, milk, cheese
Incomplete proteins:
•
foods that are missing some essential amino acids
Examples: dry beans and peas (legumes), nuts, whole
grains
Fats
Functions:
•
promotes healthy skin and normal
growth
•
carries vitamins to wherever your
body needs them
•
helps protect and cushion vital
organs as well as joints
•
insulates the body
There are two types of fats:
saturated and unsaturated
Fats
Unsaturated fats:
•
at room temperature, they are typically
in liquid form.
•
they are less harmful to the circulatory
system than saturated fats.
•
foods with a lot of unsaturated fat:
vegetable oils, nuts, olives, avocados
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Fats
Saturated fats:
• at room temperature, they are
typically in solid form
• diets with TOO MUCH saturated fat
tend to raise the level of cholesterol
in your blood, which increases your
risk for heart disease
• foods with a lot of saturated fat:
butter, meats, poultry, some dairy
products
(Cholesterol is a waxy substance found
in foods from animal sources)
Vitamins
• they regulate body
functions by helping other
nutrients do their jobs
• there are two main
categories: water-soluble
and fat-soluble
Vitamins
Water-soluble vitamins
• excess vitamins are excreted with the urine
• taking large amounts of these vitamins from supplements
overworks the kidneys and may cause damage
• ex: vitamins B1, B2, B3, folic acid, vitamin C
Fat-soluble vitamins
• stored in liver and fat until you need them
• excess amounts can build up to harmful levels
• ex: vitamins A, D, E, K
Minerals
Functions:
•
regulates body processes
•
give structure to bones and teeth
•
provide materials for healthy blood and tissue
examples: calcium, phosphorus, magnesium, and iron
-calcium, phosphorus, and magnesium help build and
maintain your bones over your lifetime
-iron helps red blood cells carry oxygen to all your body’s
cells
Water
Functions:
•
regulates body temperature
•
transports nutrients to body cells
and carries waste products away
•
aids in digestion
•
moistens body tissues such as eyes,
mouth, and nose
•
cushions your joints
•
protects your body organs and
tissues
•
•
You need a regular supply of water
to help your body perform its many
life-supporting activities (aim for 8
cups a day)
essential to life – you can only live a
few days without water