Cholesterol

Noadswood Science, 2011

Cholesterol

To understand what cholesterol is and how it can have To understand what cholesterol is and how it can have an affect on an individual’s healthan affect on an individual’s health

Wednesday, April 19, 2023

Exercise & Energy

How do you think How do you think sleeping / watching sleeping / watching television / jogging / television / jogging / swimming compare in swimming compare in terms of the energy the terms of the energy the body uses?body uses?

Activity KJ/min

Sleeping 4.5

Watching TV 7

Cycling (5mph) 21

Jogging (5mph) 40

Swimming 35

Rowing 58

Walking 14

Cholesterol

Cholesterol (CCholesterol (C2727HH4646O) is a substance found in the bloodO) is a substance found in the blood

It is made in the liver and is needed for healthy cell It is made in the liver and is needed for healthy cell membranesmembranes

Too much cholesterol in the Too much cholesterol in the blood increases the risk of blood increases the risk of heart disease, and of diseased heart disease, and of diseased arteriesarteries

Cholesterol

Cholesterol is important for a variety of body functions, Cholesterol is important for a variety of body functions, including: -including: -

Cell membranesCell membranes

HormonesHormones

Bile acidsBile acids

Insulating nerve fibresInsulating nerve fibres

Cholesterol Types

The bloodstream transports cholesterol around the The bloodstream transports cholesterol around the body attached to proteinsbody attached to proteins

The combination of cholesterol and protein is called The combination of cholesterol and protein is called lipoprotein, and there are two type: -lipoprotein, and there are two type: -

Low-density lipoproteins Low-density lipoproteins ((LDLsLDLs) - carry cholesterol ) - carry cholesterol from the liver to the cellsfrom the liver to the cells

High-density lipoproteins High-density lipoproteins ((HDLsHDLs) - carry excess ) - carry excess cholesterol back to the livercholesterol back to the liver

Cholesterol Types

LDLsLDLs are often called ' are often called 'badbad' cholesterol because they ' cholesterol because they lead to fat building up on artery walls, which causes lead to fat building up on artery walls, which causes heart disease – 70% of cholesterol consisting mostly of heart disease – 70% of cholesterol consisting mostly of fatfat

HDLsHDLs are often called ‘ are often called ‘goodgood’ cholesterol because they ’ cholesterol because they help to stop fat building up in the arteries – 20% of help to stop fat building up in the arteries – 20% of cholesterol consisting mostly of proteincholesterol consisting mostly of protein

Causes & Prevention

Causes Prevention

Diet Balanced diet

Fitness (exercise) Regular exercise

Alcohol Sensible alcohol intake

Smoking Not smoking

Family History -

Age -

Sex -

Food Types

A high proportion of HDLs to LDLs is good for a healthy A high proportion of HDLs to LDLs is good for a healthy heartheart

Monounsaturated and polyunsaturated oils (found in Monounsaturated and polyunsaturated oils (found in vegetable oils) help to reduce cholesterol levels in the vegetable oils) help to reduce cholesterol levels in the blood, and also increase the proportion of HDLs blood, and also increase the proportion of HDLs compared with LDLscompared with LDLs

There are also drugs that can improve high blood There are also drugs that can improve high blood pressure and high cholesterol levelspressure and high cholesterol levels

Fats

Molecules of vegetable oils Molecules of vegetable oils consist of glycerol and fatty consist of glycerol and fatty acidsacids

Glycerol has 3 carbon atoms Glycerol has 3 carbon atoms and fatty acids have long and fatty acids have long chains of carbon atomschains of carbon atoms

Glycerol partGlycerol part

Fatty acid Fatty acid partpart

Fatty Acids – Saturated

The fatty acids in some vegetable oils are saturated, The fatty acids in some vegetable oils are saturated, and only have single bonds between their carbon atoms and only have single bonds between their carbon atoms

Saturated oils tend to be solid at room temperature, Saturated oils tend to be solid at room temperature, and are sometimes called vegetable fats instead of oiland are sometimes called vegetable fats instead of oil

Lard is an example of a saturated oilLard is an example of a saturated oil

Fatty Acids – Unsaturated

The fatty acids in some vegetable oils are unsaturated, The fatty acids in some vegetable oils are unsaturated, and have and have double bonds between some of their carbon double bonds between some of their carbon atomsatoms

Unsaturated oils tend to be liquid at room temperature, Unsaturated oils tend to be liquid at room temperature, and are useful for frying foodand are useful for frying food

They can be divided into two categories: - They can be divided into two categories: -

Monounsaturated fats have one double bond in each Monounsaturated fats have one double bond in each fatty acidfatty acid

Polyunsaturated fats have many double bondsPolyunsaturated fats have many double bonds

Unsaturated Importance

The The carbon-carbon double bonds carbon-carbon double bonds in unsaturated oils in unsaturated oils can be detected using the elements bromine or iodinecan be detected using the elements bromine or iodine

These elements react with the double bonds in the oils, These elements react with the double bonds in the oils, and the more double bonds there are, the more and the more double bonds there are, the more bromine or iodine is used upbromine or iodine is used up

Bromine water is a dilute solution of bromine, which is Bromine water is a dilute solution of bromine, which is normally orange-brown in colour – it becomes normally orange-brown in colour – it becomes colourless when shaken with an colourless when shaken with an alkenealkene, or with , or with unsaturated fats unsaturated fats (when shaken with alkanes or (when shaken with alkanes or saturated fats, its colour remains the same)saturated fats, its colour remains the same)

Unsaturated Importance

Salt

Too much salt in the diet can lead to high blood Too much salt in the diet can lead to high blood pressure, which in turn leads to an increased risk of pressure, which in turn leads to an increased risk of heart disease and strokesheart disease and strokes

Salt is found naturally in many kinds of food, but more Salt is found naturally in many kinds of food, but more is added by food manufacturers - and many people add is added by food manufacturers - and many people add even more when they are eatingeven more when they are eating

Processed foods often have a high proportion of salt Processed foods often have a high proportion of salt and fat – salt added to food during processing accounts and fat – salt added to food during processing accounts for about two-thirds of the average salt intakefor about two-thirds of the average salt intake

Salt

On average, men in the UK eat about 10g of salt a day On average, men in the UK eat about 10g of salt a day and women about 8g a dayand women about 8g a day

However, food scientists recommend no more than 6g However, food scientists recommend no more than 6g of salt a day in the die – reducing the amount of salt in of salt a day in the die – reducing the amount of salt in the diet will help to reduce the risk of heart disease, the diet will help to reduce the risk of heart disease, and to a greater extent the risk of suffering a strokeand to a greater extent the risk of suffering a stroke

Life Expectancy

How has life expectancy changed for men and women How has life expectancy changed for men and women in this country over decade?in this country over decade?

What has driven this change?What has driven this change?

Life Expectancy

Men’s life expectancy…Men’s life expectancy…

Life Expectancy

Women’s life expectancy…Women’s life expectancy…

Life Expectancy

A huge number of changes, ranging from medicines, A huge number of changes, ranging from medicines, better food and living standards, to general awareness better food and living standards, to general awareness of life style have helped raised the life expectancy for of life style have helped raised the life expectancy for both men and women in this country over the past both men and women in this country over the past decadedecade

There are still worrying health trends in the UK, There are still worrying health trends in the UK, especially due to smoking / unhealthy diets, which are especially due to smoking / unhealthy diets, which are linked to particular areas which generally less well-off linked to particular areas which generally less well-off