Download HHD34_summary_solutions_ Ch4

CHAPTER 4
Summary questions solutions
1
The chemical compounds in carbohydrates are found in both simple and complex forms.
Carbohydrates are generally divided into two principal kinds: complex carbohydrates
(starches), which occur naturally in vegetables and grains; and simple carbohydrates
(sugars), which can be found in foods such as fruit, honey and milk. Another form of
carbohydrate is fibre. There are two main types of fibre: soluble and insoluble. In general,
dietary fibre is considered to be polysaccharides that have not been digested at the point
of entry into the large intestine.
2
There are basically two types of protein – complete and incomplete. Complete protein
provides the proper balance of the eight essential amino acids that build body tissue. It
can be found in foods of animal origin such as meats, poultry, seafood, eggs, milk and
cheese. Incomplete protein, the protein found in plant foods, lacks certain essential
amino acids. Combinations of plant foods, however, can supply the entire range of
essential amino acids. Plant foods that are high in protein include beans, lentils and
legumes, nuts and seeds, some grains such as quinoa and barley, and soy products such as
tofu.
3
Fats are classified by their different molecular structure and are broken down into the
categories of polyunsaturated, monounsaturated, saturated and trans fats.
4
Summary table:
Nutrient functions
Different types
Appropriate food
sources
Carbohydrates
Proteins
Provide the body with
Simple, complex and
Fruits, vegetables, dairy,
energy
fibre
honey
Growth, repair and
Amino acids, complete
Meat, eggs, milk, poultry
maintenance of tissue,
proteins, incomplete
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regulates specific
proteins
functions of the body
Fats
Source of energy, protect
Saturated fats,
Olive oil, avocado, nuts,
organs, help regulate
polyunsaturated fats
butter, fish
body temperature help
monounsaturated fats and
absorb and move
trans fats
nutrients around the
body, hormone
production
5
Vitamin D is essential for the absorption, regulation and utilisation of calcium and
phosphorus needed in the growth and maintenance of bones and teeth. It also helps to
maintain adequate blood levels of calcium and phosphorus, which are necessary for many
other functions of the body. A lack of vitamin D can lead to weakened bones and can
cause health issues by making it easier for bones to break under pressure. Additionally,
vitamin D plays a role in maintaining a stable nervous system, normal heart action and
normal blood clotting, as well as for the formation of some enzymes in the body. Vitamin
D is found in some high-fat foods such as butter, margarine and cream. It is also found in
oily fish such as salmon and tuna, as well as liver and kidney.
6
Two important minerals required for bone development are calcium and phosphorous.
Calcium’s primary role is the construction and maintenance of bones and teeth.
Approximately 99% of total body calcium is in the skeleton and teeth and they act as a
storage reservoir for this as well as other minerals. Phosphorus is present in bones and
teeth and combines with calcium to form calcium phosphate, which is the substance
that gives the skeleton rigidity.
Food sources required to attain these nutrients are: milk, cheese, yoghurt, almonds,
broccoli, wholegrains, beef, legumes and salt.
7
The main use of sodium by the body is the regulation of blood pressure and blood
volume.
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8
Water is considered to be an essential nutrient because it is a major component of
blood, lymph and bodily excretions and is a part of every cell in the body. It forms the
basis of blood, digestive juices, urine and perspiration. 80% of blood is water, 73% of
lean muscle, including brain tissue, is water, 25% of fat is water and 22% of bone is
water. An acquiesced environment is necessary for all chemical processes in living
cells. Water plays an important role in digestion and absorption as well as circulation
and regulation of body temperature, lubrication of joints and movement of waste
material. It’s the carrier of nutrients through the body.
9
Dietary imbalances can be caused by the overconsumption or under-consumption of
foods or nutrients.
Examples of dietary imbalances and the diseases linked to them are:
 excess sodium intake – causes cardiovascular disease including hypertension, heart
disease and stroke, osteoporosis
 decreased fruit and vegetable intake – colorectal cancer, type 2 diabetes, obesity
and cardiovascular disease
10 Other health concerns associated with overweight and obesity are:

Type 2 diabetes

Cardiovascular disease

Colorectal cancer

Stroke

Osteoporosis
Cardiovascular disease includes heart disease, stroke and hypertension.
11 Consuming foods low in fat is an important protective factor against obesity. Fats
consumed in high amounts on a regular basis will be stored by the body, and if the
intake is prolonged the fat storage will continue to increase, with little of the stored fat
being used as an energy source. Reducing the intake of energy-dense foods is essential
in order to reduce total energy intake. These foods often tend to be poor in overall
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nutrient content as they have low amounts of vitamins, minerals and fibre. A lower
consumption of these foods contributes to a reduction in total energy intake. An
improvement in micronutrient intake can be made with an increase in foods high in
fibre and energy-dilute foods, such as fruits, vegetable and wholegrains.
12 Conditions that are under the umbrella of cardiovascular disease include:
 Heart failure
 Coronary heart disease
 Peripheral vascular disease
 stroke
13 The most appropriate protective factor in the prevention of cardiovascular disease is
eating a balanced intake of a variety of healthy foods. Paying attention to what is eaten
is one of the most important preventative measures for this disease. Following a
healthy diet can minimise risk factors such as:

High blood cholesterol levels

High blood pressure

High saturated and trans fat intake

Diabetes

Overweight and obesity
14 Colorectal cancer is cancer that begins either in the colon or the rectum, or affects
either the colon or the rectum.
15 Currently, the risk for colorectal cancer is thought to be linked to high intakes of meat and
fat, and that risk can be decreased by high intakes of fruits and vegetables, dietary fibre,
folate and calcium.
16 Some dietary recommendations to help type 2 diabetes sufferers manage their illness
may be:
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
A healthy eating plan that will control blood glucose levels

Control of blood lipid levels (with cholesterol and triglyceride)

Control body weight

Eat low GI foods
17 Osteoporosis is the progressive degeneration of the structure, density and strength of
the bones. Over time, bones have less available calcium and become brittle, fragile and
tend to break, which leads to increased risk of fractures of the wrist, hip and spine.
18 Nutrients:

Protein: Protein is essential for bone growth, maintenance and renewal.

Calcium: A diet high in calcium allows adequate amounts of calcium for all functions,
including mineralisation of the bone.

Phosphorous: Aids in the absorption of calcium in the bones and teeth.

Vitamin D: Improves the absorption of calcium in the intestine and it also plays a role
in regulating the levels of calcium in the blood.
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