Health & Disease Noadswood Science, 2016

Friday, October 13, 2017 Health & Disease To identify what is meant by health and how this impacts not just the individual

Precise Learning Students should be able to describe the relationship between health and disease and the interactions between different types of disease. Health is the state of physical and mental well-being. Diseases, both communicable diseases and non-communicable, are major causes of ill health. Other factors including diet, stress and life situations may have a profound effect on both physical and mental health. Different types of disease may interact Severe physical ill health can lead to depression and other mental illness. Students should be able to: discuss the human and financial cost of these non- communicable diseases to an individual, a local community, a nation or globally explain the effect of lifestyle factors including diet, alcohol and smoking on the incidence of non-communicable diseases at local, national and global levels.

Health Health is the state of physical and mental wellbeing Diseases can be communicable or non-communicable Communicable – can spread from person to person or between animal and people (caused by organisms such as bacteria, viruses, parasites and fungi), e.g. measles, malaria, flu etc… Non-communicable – cannot spread between people or animals and people but generally last for a long time, e.g. asthma, cancer, coronary heart disease etc…

Disease Interaction Diseases can interact and cause other physical and mental health issues that don’t immediately seem related… Individuals with immune system problems might have an increased risk of suffering from communicable diseases such as flu as they are less likely to be able to defend themselves against the pathogen Some cancers can be triggered by viral infections such as hepatitis and liver cancers or human papilloma virus (HPV) infection and cervical cancer Immune system reactions in the body caused by infection by a pathogen can trigger allergic reactions

Mental Health Mental health issues such as depression can be triggered when someone is suffering from severe physical health problems, particularly if they have an impact on the person’s ability to carry out everyday activities or if they affect the person’s life expectancy

Health Factors A good, balanced diet that provides your body with everything it needs, and in the right amount is essential. A poor diet can affect both your physical and mental health Stress can have a negative impact on health Life situation can also affect health – if you cannot afford healthy food / condoms etc… to prevent sexually transmitted diseases

Energy Where do we get our energy from, and what do we use it for? Our energy is derived from food - whereas plants can produce their own energy from sunlight, we must consume food This food is our raw material - needed to make new substances for: - energy (movement etc…) growth and repair health

Balanced A balanced diet contains the different nutrients in the correct amounts, keeping us healthy Certain foods are not necessarily 'bad' for us, but eating too much of them could be Foods contain nutrients: these are substances which provide raw materials for the body (we need nutrients, along with fibre and water for a healthy diet) There are seven different nutrients, and some foods are particular rich in certain nutrients…

Food Groups What are the 7 food groups? Carbohydrates Fat Protein Vitamins Minerals Fibre Water

Essential? Nutrients are found within different foods, and they all play important roles within the body Nutrient How the body uses it Food sources it is contained in Carbohydrate To provide energy Cereals; bread; pasta; potatoes (sugars and starch) Protein For growth, making new cells and repair of our bodies Fish; meat; eggs; dairy products Fat To provide energy, as a store of energy & for insulation Butter; oil; nuts Minerals Needed in small amounts to maintain health Salt; milk (calcium); liver (iron) Vitamins Dairy foods; fruit; vegetables Fibre To provide roughage to help keep food passing through the gut Vegetables; bran; wholemeal bread Water Needed by cells and for body fluids Fruit juice; milk; water(!)

Balanced Different foods contain different substances - there is no one food that contains all the substances the body needs. Instead you must eat a wide variety of foods - balancing your diet Different people need different amounts of food. You need more food if you are particularly active, are pregnant etc… (the amount of energy food contains is measured in kilojules (kJ) - if you are more active, your kJ intake needs to be greater ) If we eat too little food, we will use up our store of fat and become too thin. If we eat too much food, especially foods rich in sugar and fat, we will increase our store of fat and become too fat

Poor Diet If you have too little of a particular nutrient, we say that you have a deficiency in that nutrient, e.g. fibre deficiency can lead to constipation Mineral deficiencies - e.g. iron deficiency can lead to anaemia (too few red blood cells); iodine deficiency can lead to a swelling in the neck called a goitre Vitamin deficiencies - e.g. vitamin A deficiency can cause blindness; vitamin C deficiency can cause scurvy (makes the gums bleed); and vitamin D deficiency can cause rickets (legs bow outwards in growing children)

Vitamins Many deficiency diseases are caused by a lack of vitamins and minerals In 1747 James Lind scientifically proved that eating fruits prevented scurvy: - He took 12 men suffering from scurvy He gave them different treatments He found those given fruits (such as lemons) were cured of the disease In 1795 the British Navy started giving lemons (or their juice) to sailors

Metabolic Rate A healthy diet contains all the different nutrients in the correct amounts, and provides the right amount of energy for each individual An unbalanced diet can lead to a person becoming malnourished – they may be too thin or too fat as a result, and they may suffer from deficiency diseases Respiration is the chemical reaction that allows cells to release energy from food – the metabolic rate is the speed at which such chemical reactions take place in the body

Metabolic Rate Metabolic rate varies because of several factors, including: - Age Gender The proportion of muscle to fat in the body The amount of exercise and other physical activity Genetic traits The metabolic rate increases as we exercise and stays high for a while afterwards

Basal Metabolic Rate Metabolic rate is the rate at which your body burns calories Basal metabolic rate (BMR) is the rate when resting You can inherit a high BMR You can also increase your BMR with more exercise (increasing your muscle to fat ratio)

Malnourishment Malnourishment is a person with an unbalanced diet – these diseases are due to malnourishment: - Anaemia – lack of iron Obesity – too much fat Kwashiorkor – too much carbohydrate and no protein Anorexia – too little food

Recommended Daily Allowance (RDA) RDA is the amount of a specific nutrient which is recommended for consumption per day – food packaging must clearly show this for each nutrient A balanced diet should contain fats, proteins and carbohydrates in roughly these amounts: carbohydrates (red), fat (yellow) and protein (blue) It should also contain minerals, vitamins, fibre and water

RDA Food labels on products show the RDA of different nutrients within the food, usually per 100g and per serving of food… Look at the food labels for a variety of foods and work out your average RDA % (are you having less than, the right amount, or more than what is recommended for a specific nutrient)?

Life Expectancy How has life expectancy changed for men and women in this country over decade? What has driven this change?

Life Expectancy Men’s life expectancy…

Life Expectancy Women’s life expectancy…

Life Expectancy A huge number of changes, ranging from medicines, better food and living standards, to general awareness of life style have helped raised the life expectancy for both men and women in this country over the past decade There are still worrying health trends in the UK, especially due to smoking / unhealthy diets, which are linked to particular areas which generally less well-off

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Practice Questions What is meant by the term health? What is the main difference between communicable and non-communicable disease? Give three factors other than disease that could affect health

Answers What is meant by the term health – the state of physical and mental wellbeing What is the main difference between communicable and non-communicable disease – communicable can be spread between people or between people and animals whilst non-communicable cannot Give three factors other than disease that could affect health – diet / stress / life situation

Practice Questions – Application The graph below shows the results of a study into the average number of colds suffered by employees in high-stress jobs and low-stress jobs in the same company per year Describe and suggest an explanation for the results

Answers The graph below shows the results of a study into the average number of colds suffered by employees in high-stress jobs and low-stress jobs in the same company per year Describe and suggest an explanation for the results – people with high-stress jobs had on average 3 more colds per year (stress can affect physical health)