Disease and response · GCSE Biology
Heart disease
GCSE Biology revision on cardiovascular disease as a non-communicable disease: diet, smoking, inactivity, genetics, statins, and lifestyle changes that reduce the risk of heart attack and stroke.
Non-communicable — not caused by pathogens. Risk: saturated fat, salt, smoking, alcohol, stress, inactivity, genetics. Reduce: exercise, balanced diet, stop smoking, statins lower cholesterol. Link to blocked coronary arteries.
The important bits
What you need to know
- 1
Cardiovascular disease (heart disease) is a non-communicable disease (NCD): it is not spread by pathogens. It includes conditions where the heart or blood vessels do not work properly, such as coronary heart disease.
- 2
Coronary heart disease: the coronary arteries that supply the heart muscle become narrowed or blocked by fatty deposits (atheroma / plaques), reducing blood flow and oxygen to cardiac muscle. This can cause angina or a heart attack.
- 3
Risk factors include: diet high in saturated fat and salt; smoking (damages arteries, raises blood pressure); excessive alcohol; lack of exercise; obesity; stress; family history (genetic predisposition).
- 4
A diet high in saturated fat can increase blood cholesterol. LDL cholesterol can deposit in artery walls. Salt can raise blood pressure, increasing strain on the heart and vessels.
- 5
Smoking increases carbon monoxide in blood (reduces oxygen carried) and nicotine raises heart rate and blood pressure. Tar damages artery lining, making plaque formation more likely.
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Lifestyle prevention: regular aerobic exercise strengthens heart and improves circulation; balanced diet low in saturated fat and salt; not smoking; limiting alcohol; maintaining healthy BMI.
- 7
Statins are drugs that lower cholesterol in the blood, slowing plaque formation. They are prescribed when lifestyle change alone is not enough. Surgery (stents, bypass) may be needed in severe cases — context beyond core GCSE.
- 8
Heart disease contrasts with communicable disease: you cannot “catch” it from cough droplets. Public health campaigns target smoking and diet. Epidemiological data link risk factors to disease rates.
Quotations worth analysing
Short evidence. Real method.
“Coronary heart disease is caused by a narrowing of the coronary arteries that supply the heart muscle.”
Name the vessels and the blockage (fatty deposits). Heart muscle needs oxygen from these arteries.
“Smoking, diet, lack of exercise and genetic factors increase the risk of cardiovascular disease.”
Give at least three factors with a mechanism each, not a bullet list without explanation.
“Statins are used to lower blood cholesterol.”
Statins are a drug intervention; lifestyle changes are the first-line prevention story.
Go deeper
Mechanism chain: saturated fat to heart attack
Saturated fat in diet → raised LDL cholesterol in blood → cholesterol deposits in coronary artery walls (plaque) → artery narrows → less oxygen to heart muscle during exertion (angina) or plaque rupture → clot blocks artery completely → heart attack (myocardial infarction). Each arrow is a mark. Salt raises blood pressure → more damage to vessel lining. Smoking adds CO and vessel damage. Exercise improves heart efficiency and can help maintain healthy weight. Write the chain, not “fat is bad”.
Go deeper
Non-communicable versus communicable in one comparison
Measles: virus, droplets, vaccine. Heart disease: lifestyle and genes, not pathogens, prevented by diet and not smoking. Cancer and diabetes are other NCDs mentioned alongside CHD in infection topics. If a question asks “why is heart disease different from malaria”, name pathogen vs no pathogen, transmission vs risk factors, antibiotic/antimalarial vs statin/lifestyle. NCDs are rising globally as diets and smoking patterns change — geography links optional.
Go deeper
Evaluate lifestyle versus statins
Lifestyle: no drug side effects, wider health benefits (fitness, lung health), but requires behaviour change and may not reverse existing damage. Statins: proven cholesterol reduction, useful if genetic high cholesterol or high risk, but possible side effects and cost to health service. Surgery: last resort when arteries critically blocked. GCSE evaluate wants benefits and drawbacks of each, then a judgement for a named patient scenario. “Everyone should take statins” is too simple.
See the idea in action
Explain how smoking increases the risk of heart disease (3 marks). Chemicals in smoke damage the lining of arteries, making fatty plaque more likely to form. Carbon monoxide reduces oxygen carried by red blood cells, so the heart must work harder. Nicotine increases heart rate and blood pressure, increasing strain on the cardiovascular system.
Exam technique
Turn knowledge into marks
State non-communicable first. Name coronary arteries and fatty deposits. Link each risk factor to a mechanism. Mention statins for high cholesterol and lifestyle changes for prevention.
Common mistakes
Do not give these marks away
- 01
Calling heart disease communicable or caused by bacteria.
- 02
Listing risk factors without explaining how they damage arteries or raise blood pressure.
- 03
Suggesting antibiotics or vaccines as treatments for coronary heart disease.
What happens in coronary heart disease?
AA virus infects the heart muscle
BCoronary arteries become narrowed by fatty deposits, reducing blood flow to the heart
CThe heart stops producing red blood cells
DWhite blood cells attack the heart as an allergy
Show the answer
Coronary arteries become narrowed by fatty deposits, reducing blood flow to the heart. CHD is non-communicable and involves atherosclerosis in coronary arteries, not infection.
Quick questions
If this is the bit you searched
Is heart disease communicable?
No. It is a non-communicable disease caused by lifestyle, genetics and other factors, not pathogens.
What are risk factors for heart disease GCSE?
Smoking, high saturated fat and salt diet, lack of exercise, obesity, excessive alcohol, stress and family history.
What do statins do?
They lower blood cholesterol, which can slow the build-up of fatty deposits in arteries.
How can you reduce the risk of heart disease?
Regular exercise, balanced diet low in saturated fat and salt, not smoking, limiting alcohol, and maintaining a healthy weight.