FOOD FUNDAMENTALS
Nutrition basics
Nutrition basics
For the body to function normally it requires fuel for energy, building
materials for growth and essential maintenance, plus a small but
vital combination of chemical ingredients to ensure its many
metabolic processes run smoothly. The body can make almost
everything it needs from the nutrients in a balanced diet.
What does the body need?
An adequate combination of essential
nutrients in our diet—water, carbohydrates,
proteins, fats, vitamins, and minerals—should
enable our bodies to work efficiently and keep
us in good health. Beyond basic nutrition,
there are other nutrients that, although our
body doesn’t necessarily need them, are
certainly beneficial, such as phytochemicals
in fruit and vegetables and fatty acids in some
fish. Nutraceuticals, or “functional foods,”
including those containing probiotics
(see p.87), are believed to have health
benefits beyond their nutritional value,
including disease prevention.
Water
Around 65 percent
of the body is made
up of water. This is
constantly being lost
through digestion,
breathing, sweating,
and urine, and it is
critical that water
is replenished at
regular intervals.
Minerals
Present in a wide variety of foods,
minerals are vital for building bones, hair,
skin, and blood cells. They also enhance
nerve function and help to turn food
into energy. Deficiencies can cause
chronic health problems.
Carbohydrates
Carbohydrates
are the body’s
primary source of
energy. The body converts simple
sugars and more complex starches
into glucose, which fuels our body
cells. Whole grains and fruits and
vegetables that are high in fiber
are the most healthy sources
of carbohydrates.
LARGE INTESTINE
Malnutrition results from a diet
that does not contain the right
amounts of nutrients. While lack of
carbohydrates and protein can lead
to major development and growth
problems, deficiency in certain
vitamins and minerals can cause
specific illnesses. For example, a
lack of iron may lead to anemia.
Overnutrition occurs when an
oversupply of nutrients causes
health problems, such as obesity
caused by a high-calorie diet.
MALNUTRITION
SUGAR
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FOOD FUNDAMENTALS
Nutrition basics
13
Building and maintaining cells
Cells are the basic functional units of the human
body that make up its diverse tissues and organs.
Every one of our trillions of cells is built and
maintained by the nutrients we get through our
diet. If, through poor nutrition, our cells are unable
to function properly, our tissues and organs can
become compromised, leading to the onset of a
host of health conditions and diseases.
Vitamins
Vitamins are vital
to the body’s
metabolic processes,
especially those linked to tissue growth
and maintenance. Most vitamins can’t
be stored in the body, so regular
intake through a balanced diet is
essential. As with minerals, a lack
of certain vitamins can lead
to deficiency diseases.
Fats
Fats are a rich source of energy and help
in the absorption of fat-soluble vitamins.
Essential fatty acids cannot be made by
the body and must be obtained from
food. The healthiest fat sources
include dairy, nuts, fish, and
vegetable-based oils.
Proteins
Proteins are broken down into amino
acids. Although they may be used by
the body for energy, their main role
is as building blocks of tissue growth
and repair. Healthy protein sources
include beans, lean meat,
dairy, and eggs.
SMALL INTESTINE
1 in 3
THE PROPORTION OF
PEOPLE WORLDWIDE
THAT SUFFER FROM
MALNUTRITION
WHAT IS A
“HEALTHY DIET”?
A healthy diet is one that
provides the body with the right
amounts of all the essential
nutrients it needs from a variety
of different food sources. This
should help you achieve and
maintain a healthy
body weight.
NUCLEUS
AMINO
ACIDS
FATTY
ACIDS
CYTOPLASM
Cell support
A broad range of nutrients
support cell formation and
growth. A cell’s main
structures are built from
amino acids and some
fatty acids, and every cell
is fueled by carbohydrates
and other fatty acids.
C
E
L
L
M
E
M
B
R
A
N
E
S
T
O
M
A
C
H
C
E
L
L
S
T
R
U
C
T
U
R
E
Getting what we need
When we eat food, it passes into our
digestive system to be broken down and
absorbed (see pp.20—21). Most nutrients
are absorbed in the small intestine.
US_012-013_Nutrition_basics.indd 13 03/02/2017 10:12
12
FOOD FUNDAMENTALS
Nutrition basics
13
Building and maintaining cells
Cells are the basic functional units of the human
body that make up its diverse tissues and organs.
Every one of our trillions of cells is built and
maintained by the nutrients we get through our
diet. If, through poor nutrition, our cells are unable
to function properly, our tissues and organs can
become compromised, leading to the onset of a
host of health conditions and diseases.
Vitamins
Vitamins are vital
to the body’s
metabolic processes,
especially those linked to tissue growth
and maintenance. Most vitamins can’t
be stored in the body, so regular
intake through a balanced diet is
essential. As with minerals, a lack
of certain vitamins can lead
to deficiency diseases.
Fats
Fats are a rich source of energy and help
in the absorption of fat-soluble vitamins.
Essential fatty acids cannot be made by
the body and must be obtained from
food. The healthiest fat sources
include dairy, nuts, fish, and
vegetable-based oils.
Proteins
Proteins are broken down into amino
acids. Although they may be used by
the body for energy, their main role
is as building blocks of tissue growth
and repair. Healthy protein sources
include beans, lean meat,
dairy, and eggs.
SMALL INTESTINE
1 in 3
THE PROPORTION OF
PEOPLE WORLDWIDE
THAT SUFFER FROM
MALNUTRITION
WHAT IS A
“HEALTHY DIET”?
A healthy diet is one that
provides the body with the right
amounts of all the essential
nutrients it needs from a variety
of different food sources. This
should help you achieve and
maintain a healthy
body weight.
NUCLEUS
AMINO
ACIDS
FATTY
ACIDS
CYTOPLASM
Cell support
A broad range of nutrients
support cell formation and
growth. A cell’s main
structures are built from
amino acids and some
fatty acids, and every cell
is fueled by carbohydrates
and other fatty acids.
C
E
L
L
M
E
M
B
R
A
N
E
S
T
O
M
A
C
H
C
E
L
L
S
T
R
U
C
T
U
R
E
Getting what we need
When we eat food, it passes into our
digestive system to be broken down and
absorbed (see pp.20—21). Most nutrients
are absorbed in the small intestine.
US_012-013_Nutrition_basics.indd 13 03/02/2017 10:12
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