Healthy Lifestyle

David TsangCenter for Promoting Science EducationFaculty of Science and Department of Biochemistry, CUHK

HEALTH

• WHO definition

“ A state of complete physical, social and mental well-being, and not merely the absence of disease or infirmity.”

“ 一個完整狀態於生理、心理社交及精神三方面的健康 ，不單 只是沒有病痛或衰弱。”• Health is a POSITIVE concept 正面的概念 : PERSONAL responsibilities DUTY to fellow beings, surroundings, environment

• To be HEALTHY is to be in a state of HOMEOSTASIS with one’s surrounding.

一種個人的環境與其體內平衡的狀態

FACTORS AFFECTING HEALTH

ILLNESS HEALTH

Outside Factors外在因素

Occupation 職業

Social Class 社會地位

Habitat 棲息地

Environment 環境

Stress 壓力

Education 教育

Nutrition 營養

Habits / Lifestyle習慣 / 生活模式

Determinants of Health – Example:

• Class• Gender• Age• Ethnicity

• Housing• Environment• Access to health service

• Nutrition

• Smoking

• Physical activities

• Psychological

factors

• Cholesterol• Blood• Obesity

CoronaryHeart Disease

Key socialstratificationfactors

Environmentalfactors

Life stylefactors

Physiologicalfactors

Follows the Follows the portionsportions of the food pyramid of the food pyramid Eats three regular balanced mealsEats three regular balanced meals

(to avoid hunger)(to avoid hunger) Has less processed foods Has less processed foods ((contain additivescontain additives)) Eats a variety of foods Eats a variety of foods (to obtain all nutrients)(to obtain all nutrients) Drinks plenty of water Drinks plenty of water (to remove wastes)(to remove wastes) Gives you a healthy weight Gives you a healthy weight if you exercise if you exercise regularlyregularly

Some characteristics of a balanced diet

Stress the importance of each

We should try toWe should try to

Promote optimal healthPromote optimal health and and Prevent diseasesPrevent diseases

Eating a balanced diet is not enough

NOT just meets nutritional needs

Stress:Stress: How do good eating habits lead to How do good eating habits lead to good health?good health?

How do poor eating habits lead to How do poor eating habits lead to health problems?health problems?

(Good habits are easily formed during (Good habits are easily formed during childhood/adolescent)childhood/adolescent)

Eating habits

Activity:1.Why?2.Can we change

their habits?

We should not eat too muchWe should not eat too much We should not eat too much fatty We should not eat too much fatty

foodsfoods Why is excess energy stored as fat?Why is excess energy stored as fat?

Some puzzles

Metabolism of carbohydrates, fats Metabolism of carbohydrates, fats and proteinsand proteins

CarbohydratesCarbohydrates Fats Fats Proteins Proteins

-amylase-amylase lipaseslipases

proteasesproteases

MonosaccharidesMonosaccharides Fatty acidsFatty acids Amino acids Amino acids

Fat synthesis(Excess calories)

ATP productionvia TCA cycle

Acetylcoenzyme A(Common intermediate)

Why is excess energy stored as fat?

• A fat (lipid) molecule contains more energy

• fat : carbohydrate is 8:6 ATP

• Special cells to store fat (fat cells)

FoodFood Caloric content (Kcal/g)Caloric content (Kcal/g)

CarbohydratesCarbohydrates 44

ProteinProtein 44

FatFat 99

AlcoholAlcohol 77

CHO ratio and energy contentsCHO ratio and energy contents

SubstanceSubstance FormulaFormula EnergyEnergy

(Kcal/g)(Kcal/g)

GlucoseGlucose CC66HH1212OO66 4 4

EthanolEthanol CC22HH66OO11 77

Palmitic acidPalmitic acid CC1616HH3232OO22 99

Your deduction is…….

Activity

WHY? Different lifestyles? Economic development?

• BODY MASS INDEX (BMI) 體重指數18.5-22.9 (normal); 23-24.9 (overweight);

25-29.9 (moderately obese) & >30 (grossly obese)• WAIST CIRCUMFERENCE 腰圍

At risk: Men > 90cm (35.5 inches) Women > 80cm (31 inches)• WAIST TO HIP CIRCUMFERENCE RATIOS (WHR) 腰圍與臀圍比例

At risk: WHR > 1; Men < 0.9 and Women < 0.8 are safe• IMAGING 成像技術

(WHO figures for ASIANS)

Body fat distribution measured by

Which is more accurate and reliable?

Main areas of fat StorageMain areas of fat Storage

WomenWomen– BreastsBreasts– WaistWaist– HipsHips– ButtocksButtocks

MenMen– ChestChest– AbdomenAbdomen– ButtocksButtocks

Causes of obesityCauses of obesity

OvereatingOvereating

Energy-rich dietsEnergy-rich diets

Lack of exerciseLack of exercise

Genetics (leptin) Genetics (leptin) **

Metabolic (endocrine disorders) Metabolic (endocrine disorders) **

Psychological/Social (stress, Psychological/Social (stress, anorexia nervosa, bulimia nervosa)**

Encourage your students to find the reasons and supporting evidence

• Coronary Heart Disease 冠心病• High blood pressure 高血壓• Stroke 中風• Diabetes 糖尿病• High Cholesterol level 高膽固醇• Obstructive sleep apnoea 睡眠窒息症• Some types of Cancer (colon, breast) 某些癌症 ( 直腸

癌、乳癌 )• Arthritis / Back pain 關節炎及背痛• Gallstones 膽石• Low self-esteem 心理問題 ( 低自我形像 )

OBESITY ASSOCIATED DISEASES超重及過度肥胖的人仕容易患上之疾病

OBESITY 肥胖症

An escalating problem

HONG KONG

1995/96 males : 5.4% obese ( i.e. BMI >30 ) females : 7% 2002 males : 41.7% obese females : 40%

Coronary heart disease 1995 males : 12% females : 8% 2002 males : 68% females : 38.4%

藥物有「副作用」 (Side effects)

不可亂「食」 , 依指示服用 (According to instruction)

Take drugs? Appetite lowering ↑ Metabolism↓ Absorption

Body Slimming

•The recipe for effective weight loss is a combination of motivation, physical activity, and a balanced diet plus

calorie restriction

• Find a support system (friends, support groups, family…)

A suggested weight reduction method

Exercise & Rest

Exercise > 30 min, why?Exercise > 30 min, why?

30 min: utilize carbohydrates30 min: utilize carbohydrates (glycogen (glycogen → →→ → glucose glucose → →→ → energy) energy)

> 30 min: utilize fats> 30 min: utilize fats

Caloric expenditure for different Caloric expenditure for different physical activitiesphysical activities

Physical activityPhysical activity Caloric expenditureCaloric expenditure(Kcal/min)(Kcal/min)

Very light Very light (Sleeping, lying, driving..)(Sleeping, lying, driving..)

1.0-2.51.0-2.5

LightLight(Walking 2.5-3.5 mph, shopping..(Walking 2.5-3.5 mph, shopping..

2.5-5.02.5-5.0

ModerateModerate(Walking 3.5-4 mph, cycling..(Walking 3.5-4 mph, cycling..

7.5-10.07.5-10.0

HeavyHeavy(Walking uphill, swimming…(Walking uphill, swimming…

10.0-12.510.0-12.5

Very heavyVery heavy(Running, climbing…..(Running, climbing…..

12.5-15.012.5-15.0

細胞能有效地進行再生過程細胞能有效地進行再生過程能排走細胞的代謝廢物能排走細胞的代謝廢物能迅速回復體力能迅速回復體力增強身體的免疫水平增強身體的免疫水平影響生長激素的分泌週期（青少年）影響生長激素的分泌週期（青少年）減輕精神壓力減輕精神壓力

休息對健康的好處

運動的好處運動的好處

運動能增強體適能，這包括：運動能增強體適能，這包括： 促進心血管的健康促進心血管的健康 增加肺容量增加肺容量 增強肌肉強度及持久力增強肌肉強度及持久力 消耗體內多餘脂肪，有助控制適消耗體內多餘脂肪，有助控制適當當 的體重的體重 維持肌肉骨骼的柔軟度和堅韌維持肌肉骨骼的柔軟度和堅韌 促進精神健康促進精神健康

Mental disorders

and

Drug abuse

Central Nervous System

Controls all activities in our body

(like the CPU of a computer)

Brain

Spinal cord

Structures: Brain & Spinal cord

Functions:

Brain: controls thinking & behaviour

Spinal cord: Transmit signals from the brain to other par

ts and back

Parietal lobe:

movement,reasoning, memory, etc.

Spinal cord:

convey motor & sensory messages

Cerebellum:

modulate motoractivities, etc

Occipital lobe:

vision, etc

Temporal lobe::

memory, speech, etc

Frontal lobe:

cognition, judgment, speech, thinking, writing, etc

Brain Function

Different areas perform different functions

突觸裂隙

突觸前細胞

突觸後細胞

Neurons 神經細胞

細胞核軸索( 突 )

Note: Neurons are not in direct contact with one another

Axon

Synaptic cleft

Nucleus

Pre-synaptic neuron

Post-synaptic neuron

Any Any factor factor that affects that affects neurotransmissionneurotransmission may may

lead to lead to behavioral changesbehavioral changes

Mental Health & Community Related Health

Problems

• A CUHK study in 1999 targeting 26,000 secondary and primary students found 12% had psychological and emotional problems, 14% had suicidal ideas in the past

• About 20% of school children enrolled in 2002 in the Student Health Service scheme were found to have ‘psychosocial

problems’

• Another study: 60% of young males of 16 years and over had smoking experience and 48% for females; 37% of children studied commenced smoking at age of 10 years

• Drug abuse problem among young persons is also increasing

Mental health-ClassificationMental health-Classification

NeurosisNeurosis– Anorexia/Bulimia nervosa (?) Anorexia/Bulimia nervosa (?)

PsychosisPsychosis– SchizophreniaSchizophrenia– DepressionDepression– Maniac depressionManiac depression– Alzheimer disease (Dementia)Alzheimer disease (Dementia)– Parkinson’s disease (?)Parkinson’s disease (?)– Anorexia/Bulimia nervosa (?)Anorexia/Bulimia nervosa (?)

Causes of Mental DisordersCauses of Mental Disorders

Inheritance (not 100%)Inheritance (not 100%)

Brain damageBrain damage– DiseasesDiseases– InjuriesInjuries

Environmental factorsEnvironmental factors– StressesStresses– Pollutants (Chemicals)Pollutants (Chemicals)– Social relationshipSocial relationship– EmotionalEmotional– OthersOthers

Imbalance(s) of a neurotransmitter(s) in different parts of the brain

Symptoms

Question: Are students required to know all symptoms of a mental disorder?

Source:Wong, D.F.K. (2000) Socio-economic changes and mental health: Setting a new agenda for prevention strategies in Hong Kong. International Journal of Psychosocial Rehabilitation. 4, 111-134

0

10

20

30

40

50

Anxiety Symptoms DepressedMoods**

SleepingDisturbances*

VocationalProblems

InterpersonalRelationshipProblems*

20 or below

20-30

30-40

40-60

60 or over

Per

cen

tag

e(%

)

Distribution of Types of Presenting Problems by Age of Callers of the 97 –98 Sample

(df = 4) *P>0.05, **P>0.01, ***P>0.001

Drug AbuseDrug Abuse

Scientific issues:• How do drugs affect behaviour? • What are the effects of drug abuse?• Why do some people use drugs?• Do abusers display any abnormal signs of habits?

We do not use ‘drugs’, why should we study “Drug abuse”? …….Your students

Social problems:• Causes heavy financial loss in society• Rapid increase in drug abusers recently• Related to organized crime or triad society activities

Path Leading to Addiction ( 成癮 )

Experimental use 試探性使用 Social use 社交性使用 Episodic abuse 偶發性使用

Tolerance 耐藥性增加 Addiction 成癮

Other addictions: Internet, gambling….

Number of Persons Arrested for Drug OffencesNumber of Persons Arrested for Drug Offences

0

2000

4000

6000

8000

10000

12000major offences

minor offences

YearYear

Per

son s

Arr

este

dP

ers o

n s A

r re s

t ed

What are major and minor offence?

Activities in Class

Why was there an increase in drug-related offences in 1994-1996? Why there was a drop from 1997- 2000?

Sources:Hong Kong Narcotics Report

Central Registry of Drug Abuse

Drug Information Centre (Narcotics Division)

http://www.nd.gov.hk/druginfo.htm

正常神經細胞

受損害的神經細胞

康復後的神經細胞

康復後的神經細胞比受損害前的明顯短了。

中樞神經細胞不能重生

Effect of Multi-drugs【 Depressant + Stimulant 】

XXXMuch Greater Effects

Brain death ( 植物人 )

DeathDeath

No Effect??

Impurities

Overdose [Concentrations vary]

Poly-drug use

Drug abuse causes death

Divide students into groups Drug dealers → persuade their (potential) customers Drug addicts → craving for drugs Smart students → refuse buying drug from a dealer Ecstasy pills → what they would do after taken A social worker → approached by a drug addict for help Parents → learned their children are drug addicts

Activity/Role play

Debate/DiscussionDebate/Discussion‘‘Soft’ drugs are less harmful than ‘hard’ drSoft’ drugs are less harmful than ‘hard’ drugs.ugs.Drinking beer is less harmful than drinking Drinking beer is less harmful than drinking spirits/whiskies/brandies.spirits/whiskies/brandies.Alcohol is a ‘Alcohol is a ‘stimulant drugstimulant drug’ to cure depres’ to cure depression and can cheer oneself up when one is sion and can cheer oneself up when one is in the blues (depressed).in the blues (depressed).Drinking heavily for many years does no hDrinking heavily for many years does no harm because your body gets used to it. arm because your body gets used to it.

↑Interest, Understanding & Confidence

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Thank youThank you