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Think about…
23.1 Meaning of health and disease
23.2 Effects of lifestyles on health
Recall ‘Think about…’
Summary concept map
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A Hong Kong Health Index survey has
recently been completed.
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It measured the health status of Hong Kong
people.
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Some of the survey results:
16.1% of people
have chronic
diseases (長期病患)
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Some of the survey results:
40.1% of people
do not exercise
regularly
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Some of the survey results:
30.4% of people
have had sleep
problems in the
past week
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1
What is health
Are people without
diseases considered
healthy
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2
What are the
health benefits of
regular exercise
9
3
How is health
affected by
insufficient sleep
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23.1 Meaning of health
and disease
• a disease is a condition in which any
body part cannot function normally
• recognized by signs (病徵) and
symptoms (症狀)
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23.1 Meaning of health and disease
What is a sign?
• can be noticed by the patient, doctor,
nurse and other observers
• examples: fever and
irregular heart rate
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23.1 Meaning of health and disease
What is a symptom?
• can only be felt by the patient
• examples: headache and tiredness
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23.1 Meaning of health and disease
Meaning of health
by World Health Organization (WHO)
(世界衛生組織):
• a state of complete physical, mental
and social well-being
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23.1 Meaning of health and disease
Meaning of health
physical
• the body parts function normally
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23.1 Meaning of health and disease
Meaning of health
physical
mental
• the body parts function normally
• one feels good about oneself
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23.1 Meaning of health and disease
Meaning of health
physical
mental
Health
social
• the body parts function normally
• one feels good about oneself
• one gets along well with other people
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23.1 Meaning of health and disease
1
A disease is a condition in which
any body part cannot function
normally .It is recognized by signs
and symptoms .
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23.1 Meaning of health and disease
2 Health is a state of complete
physical , mental and social
well-being.
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23.2 Effects of lifestyles on health
• some diseases (e.g. genetic diseases)
are inborn
• many other diseases are related to the
way we live (e.g. diet, exercise)
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23.2 Effects of lifestyles on health
Diet
• a balanced diet helps
maintain a healthy body
and provides a suitable
amount of energy
food pyramid
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23.2 Effects of lifestyles on health
1 Eating too little
• deficiency in any one food substance
can lead to deficiency diseases
Deficiency in
Deficiency disease
Protein
Kwashiorkor
Vitamin A
Night blindness
Vitamin C
Scurvy
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23.2 Effects of lifestyles on health
1 Eating too little
• deficiency in any one food substance
can lead to deficiency diseases
Deficiency in
Deficiency disease
Vitamin D
Rickets
Calcium
Rickets
Iron
Anaemia
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23.2 Effects of lifestyles on health
1 Eating too little
• no single food can provide all food
substances
 people who are selective about
their diets must plan their diets well
e.g. vegetarians
should eat a
variety of
plant foods
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23.2 Effects of lifestyles on health
1 Eating too little
• people with anorexia
nervosa refuse to eat
 thin and weak
 various deficiency
diseases and even death
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23.2 Effects of lifestyles on health
2 Eating too much
• excess cholesterol (膽固醇) can block
the arteries to the cardiac muscles
 heart attack (心臟病發作) and
stroke (中風)
cholesterol
wall of artery
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23.2 Effects of lifestyles on health
2 Eating too much
• acid is produced when sugar is
metabolized by oral bacteria
 acid dissolves the enamel of teeth
 tooth decay (蛀牙)
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23.2 Effects of lifestyles on health
2 Eating too much
• some foods like salted fish have a
high salt content
 high blood pressure (高血壓)
 damage to the brain and kidneys
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23.2 Effects of lifestyles on health
2 Eating too much
• when energy input > energy output,
we gain weight
 obesity
 heart disease,
diabetes and
arthritis (關節炎)
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23.2 Effects of lifestyles on health
Exercise
1 Strengthen the heart and lungs
• aerobic exercise (需氧運動) involves
contraction of large muscles
jogging
swimming
cycling
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23.2 Effects of lifestyles on health
Exercise
1 Strengthen the heart and lungs
• the heart and lungs work harder to meet
the body’s increased oxygen demand
• 30 minutes of aerobic exercise daily
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23.2 Effects of lifestyles on health
Exercise
2 Keep bones and muscles strong
• strength training exercise requires
muscles to work against force or weight
 increases bone density
 muscles get stronger and bigger
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23.2 Effects of lifestyles on health
Exercise
3 Improve suppleness
• some exercise involves a range of
movement of joints
 improves suppleness (柔軟性)
 less likely to have injuries or pain
suffered by stiffness in joints
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23.2 Effects of lifestyles on health
Exercise
4 Promote mental and
social well-being
• exercise stimulates endorphin (內啡肽)
production
• endorphins reduce the feeling of pain
and anxiety
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23.2 Effects of lifestyles on health
Exercise
4 Promote mental and
social well-being
• exercise enables people to gather
with friends
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23.2 Effects of lifestyles on health
Exercise
5 Reduce the risk of diseases
• when exercising, energy is obtained by
breaking down glycogen and fats
 manage body weight
and prevent obesity
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23.2 Effects of lifestyles on health
Exercise
5 Reduce the risk of diseases
• regular exercise lowers the risk of:
- high blood pressure, heart disease
and stroke
- osteoporosis (骨質疏鬆症)
- diabetes
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23.2 Effects of lifestyles on health
Rest
• helps recover both physically
and mentally
• adults need 7–9 hours of sleep each day
• teenagers need 9.5 hours
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23.2 Effects of lifestyles on health
Rest
• during sleep, the release of growth
hormone (生長激素) is at its peak
• growth hormone stimulates
growth
• insufficient sleep affects our alertness,
judgment, reaction time, memory
and mood
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23.2 Effects of lifestyles on health
Rest
• insufficient sleep also links to:
- high blood pressure
- diabetes
- obesity
- depression (抑鬱症)
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23.2 Effects of lifestyles on health
Rest
• develop good rest and sleep habits:
Avoid working continuously for long
hours. Take a break to recover from
stress and fatigue.
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23.2 Effects of lifestyles on health
Rest
• develop good rest and sleep habits:
Avoid heavy meals close to bedtime.
Digestive processes can disturb sleep.
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23.2 Effects of lifestyles on health
Rest
• develop good rest and sleep habits:
Maintain regular bedtime and
waking time.
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23.2 Effects of lifestyles on health
Rest
• develop good rest and sleep habits:
At bedtime, keep your bedroom dark
and quiet.
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23.2 Effects of lifestyles on health
Old people need less sleep.
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23.2 Effects of lifestyles on health
In fact, old people have less
sleep because they are more
easily disturbed by light or
noise than young people.
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23.2 Effects of lifestyles on health
Personal hygiene
• many diseases are caused by viruses,
bacteria, protists, fungi, etc.
• keeping ourselves clean can reduce the
chance of catching or spreading diseases
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23.2 Effects of lifestyles on health
1 Hygiene of hair
• sebum (皮脂) is an oily substance
secreted from the skin
 makes the hair and skin supple
• excess sebum may result in the
formation of dandruff (頭皮屑)
• hair should be washed with mild
shampoo at least twice a week
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23.2 Effects of lifestyles on health
1 Hygiene of hair
• after washing, dry the hair thoroughly
• do not share combs and hats
 prevent the spread of
head lice (頭虱)
• head lice suck blood from
the scalp, causing itchy spots
 scratching may lead to
inflammation
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23.2 Effects of lifestyles on health
2 Hygiene of hands
• hands can pick up disease-causing
agents easily
• we may catch diseases when touching
our eyes, nose or mouth with
contaminated hands
• wash our hands
frequently
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23.2 Effects of lifestyles on health
3 Hygiene of skin
• our body smells when bacteria break
down chemicals in the sweat
• take a bath every day to
reduce body odour (體臭)
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23.2 Effects of lifestyles on health
3 Hygiene of skin
• athlete’s foot (腳癬／香港腳) is a skin
disease caused by fungi
• to prevent this:
- dry the skin with a towel
after taking a bath
- do not share towels,
socks and other clothes
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23.2 Effects of lifestyles on health
4 Oral hygiene
• good oral hygiene reduces bad breath
and prevents dental diseases
• good habits for oral health:
a) brush your teeth properly and
regularly
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23.2 Effects of lifestyles on health
4 Oral hygiene
b) use toothpaste containing fluoride
(氟化物)
- alkaline in nature:
neutralizes the acid
produced by oral
bacteria
- fluoride: helps prevent
tooth decay
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23.2 Effects of lifestyles on health
4 Oral hygiene
b) use toothpaste containing fluoride
(氟化物)
- abrasive (磨料):
removes plaque
(牙菌膜)
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23.2 Effects of lifestyles on health
4 Oral hygiene
c) use dental floss (牙線)
to remove plaque
between teeth
d) do not eat too much
sugary food and bite
very hard materials
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23.2 Effects of lifestyles on health
4 Oral hygiene
e) have a balanced diet with adequate
calcium, phosphorus and vitamin D
f) have a dental check-up at least twice
a year
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23.2 Effects of lifestyles on health
Smoking, alcohol and
drug abuse
1 Smoking
• cigarette smoke contains
over 4000 chemicals:
- tar (焦油)
- nicotine (尼古丁)
- carbon monoxide
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23.2 Effects of lifestyles on health
i) Smoking-related diseases
• tar and other chemicals may lead to
cancers of the mouth, throat, stomach,
pancreas and kidneys
• responsible for 90% of
lung cancer cases
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23.2 Effects of lifestyles on health
annual death rate per
100 000 men
i) Smoking-related diseases
300
250
200
150
100
50
0
0
1-14 15-25 >25
number of cigarettes
smoked per day
60
23.2 Effects of lifestyles on health
i) Smoking-related diseases
• tar irritates the lining of air passages
 chronic bronchitis
(慢性支氣管炎)
- air passages are narrowed
 less oxygen reaches
the air sacs
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23.2 Effects of lifestyles on health
i) Smoking-related diseases
• emphysema (肺氣腫)
- walls of the air sacs
are broken down
- surface area for gas
exchange is reduced
 difficulty in breathing
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23.2 Effects of lifestyles on health
i) Smoking-related diseases
• nicotine increases heart rate and causes
constriction (收縮) of blood vessels
• carbon monoxide reduces ability of red
blood cells to carry oxygen
 increased risk of heart attack and
other heart diseases
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23.2 Effects of lifestyles on health
i) Smoking-related diseases
• nicotine is addictive
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23.2 Effects of lifestyles on health
ii) Effects of smoking on pregnancy
• chance of miscarriage (流產)
increases
• chance of premature delivery
(早產) increases
• babies born are smaller and lighter
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23.2 Effects of lifestyles on health
iii) Passive smoking (吸食「二手煙」)
• increases the risk of:
- lung cancer
- asthma (哮喘)
- heart diseases
• smoking in public areas
is banned in HK
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23.2 Effects of lifestyles on health
2 Alcohol abuse (酗酒)
• drinking too much alcohol or
too often leads to health, work
or relationship problem
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23.2 Effects of lifestyles on health
i) Immediate effects of alcohol
• a depressant (抑制藥)
 slows down the function of
central nervous system
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23.2 Effects of lifestyles on health
i) Immediate effects of alcohol
• a depressant (抑制藥)
• affects:
- judgment
- physical co-ordination
- blurred vision
- slurred speech
- loss of balance
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23.2 Effects of lifestyles on health
i) Immediate effects of alcohol
• drinking a large quantity
at one time:
- unconsciousness
- a coma
- death
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23.2 Effects of lifestyles on health
ii) Long-term effects of alcohol
• drinking a large quantity over time
causes addiction and other problems:
- inflammation of stomach lining,
pancreas and liver
- cirrhosis (肝硬化)
fibrous scar
tissue
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23.2 Effects of lifestyles on health
ii) Long-term effects of alcohol
• drinking a large quantity over time
causes addiction and other problems:
- high blood pressure,
heart disease and stroke
- cancers of the mouth,
oesophagus and throat
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23.2 Effects of lifestyles on health
iii) Effects of alcohol on pregnancy
• alcohol can pass through the placenta
rapidly and harm the foetus
• increases the risk of:
- miscarriage
- baby born dead
- low birthweight
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23.2 Effects of lifestyles on health
iii) Effects of alcohol on pregnancy
• babies whose mothers drink heavily
are more likely to have:
- mental retardation
- poor coordination
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23.2 Effects of lifestyles on health
3 Drug abuse (濫用藥物)
• taking of drugs without following
medical advice
• use of dangerous drugs for
non-treatment purposes
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23.2 Effects of lifestyles on health
3 Drug abuse (濫用藥物)
• some commonly abused drugs:
Heroin
Cannabis
MDMA
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23.2 Effects of lifestyles on health
3 Drug abuse (濫用藥物)
• some commonly abused drugs:
Ketamine
MethylCough
amphetamine medicine
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23.2 Effects of lifestyles on health
3 Drug abuse (濫用藥物)
• health problems caused by heroin:
- breathing and menstrual problems
- overdose may result in a coma
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23.2 Effects of lifestyles on health
3 Drug abuse (濫用藥物)
• health problems caused by cannabis,
MDMA, ketamine or methylamphetamine:
- thinking is affected
- reduced concentration, poor motor
control and slow response
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23.2 Effects of lifestyles on health
3 Drug abuse (濫用藥物)
• many drugs are addictive
 withdrawal symptoms (戒斷症狀)
occur when stop taking drugs
• many drugs have interactions with
other substances
 death
80
23.2 Effects of lifestyles on health
1
Deficiency in
Deficiency disease
Protein
Kwashiorkor
Vitamin A
Night blindness
Vitamin C
Scurvy
81
23.2 Effects of lifestyles on health
1
Deficiency in
Deficiency disease
Vitamin D
Rickets
Calcium
Rickets
Iron
Anaemia
82
23.2 Effects of lifestyles on health
2
Excess of
Health problem
Cholesterol
Heart attack , stroke
Sugar
Tooth decay , obesity
Salt
High blood pressure
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23.2 Effects of lifestyles on health
3
Health benefits of exercise:
a Exercise strengthens the heart
and lungs .
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23.2 Effects of lifestyles on health
3
Health benefits of exercise:
b Exercise keeps bones and
muscles strong.
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23.2 Effects of lifestyles on health
3
Health benefits of exercise:
c Exercise improves suppleness
of the body.
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23.2 Effects of lifestyles on health
3
Health benefits of exercise:
d Exercise promotes mental
and social well-being.
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23.2 Effects of lifestyles on health
3
Health benefits of exercise:
e Exercise reduces the risk of
diseases such as diabetes.
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23.2 Effects of lifestyles on health
4
Insufficient sleep affects alertness,
judgment, reaction time , memory
and mood. It is also linked with
high blood pressure, diabetes,
obesity and depression.
89
23.2 Effects of lifestyles on health
5
Hand washing can remove
disease-causing agents from our
hands. This reduces our risk of
catching and spreading diseases.
90
23.2 Effects of lifestyles on health
6
Smoking can cause lung cancer,
chronic bronchitis , emphysema
and heart diseases. Smoking
during pregnancy can also lead to
miscarriage and premature
delivery .
91
23.2 Effects of lifestyles on health
7a
Immediate effects of alcohol
include poor judgment and
physical co-ordination, blurred
vision , slurred speech and
loss of balance.
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23.2 Effects of lifestyles on health
7b Long-term consumption of alcohol
can lead to addiction ,
inflammation , cirrhosis, high
blood pressure, heart disease,
stroke and cancer .
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23.2 Effects of lifestyles on health
8
Drug abuse is the taking of drugs
without following medical advice ,
or the use of dangerous drugs for
non-treatment purposes.
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23.2 Effects of lifestyles on health
9
Drug abuse can cause breathing
and menstrual problems, affect
thinking , lead to reduced
concentration, poor motor control ,
slow response , a coma or even
death.
95
1
What is health? Are people without
diseases considered healthy?
Health is not just an absence of disease.
It is a state of complete physical, mental
and social well-being.
96
2
What are the health benefits of
regular exercise?
Regular exercise benefits different body
parts, such as the heart, and promotes
mental and social well-being.
97
3
How is health affected by
insufficient sleep?
People without sufficient sleep think and
act slowly. Lack of sleep is also linked
with high blood pressure, diabetes,
obesity and depression.
98
Health
is not just an
absence of
includes
disease
mental
physical
social
well-being well-being well-being
99
Health
affected by
diet
rest
exercise
personal
hygiene
smoking, alcohol
and drug abuse
100