Risk Factors and Lifestyle Effects on Health (Part 2/2) Revision Notes | GCSE OCR Foundation Biology

What this lesson covers

Explore how lifestyle factors like diet, smoking, alcohol and exercise affect non-communicable diseases, understanding risk factors and their mechanisms

• Explain the difference between proven causal mechanisms and correlational risk factors
• Evaluate how multiple factors interact to cause disease
• Apply knowledge of risk factors to assess disease prevention strategies
• Analyse epidemiological data to identify patterns in disease causation

Key ideas to keep in view

Use this lesson to stay inside B6.3 Monitoring and maintaining health while connecting the detail back to the wider B6: Global challenges topic.

• B6: Global challenges
• B6.3 Monitoring and maintaining health
• GCSE OCR Foundation Biology

Lesson notes preview

Read the core explanations from Risk Factors and Lifestyle Effects on Health (Part 2/2) before testing yourself from memory.

• 1. The Evidence Problem - Proven vs Suspected
• Here's the challenge: some risk factors have rock-solid proof of how they cause disease, while others just show up together with disease in the data. The difference matters for your exams and for real medicine.
• A proven biological pathway showing exactly how a risk factor causes disease. Established through controlled experiments and research.
• Think of smoking and lung cancer. We don't just know they're linked - we know exactly how tar damages lung cells, triggers mutations, and leads to tumours. That's a proven causal mechanism.
• But what about stress and heart disease? People with high stress do get more heart attacks, but we can't prove stress directly damages heart muscle. The mechanism isn't fully understood yet.
• Let's look at risk factors where scientists have cracked the code - they know exactly what's happening inside your body.
• Smoking → Lung cancer: Tar contains over 70 carcinogens. These chemicals bind to DNA in lung cells, causing mutations. Mutated cells divide uncontrollably, forming tumours. We can trace every step.
• High blood pressure → Stroke: Excessive pressure damages artery walls. Damaged areas attract blood clots. If a clot blocks a brain artery, brain tissue dies. Clear cause and effect.
• UV radiation → Skin cancer: UV rays damage DNA in skin cells. The cell's repair mechanisms can't keep up. Damaged cells become cancerous and multiply rapidly.
• Many risk factors show strong statistical links to disease, but we haven't figured out the biological mechanism yet. This doesn't make them less important - just less understood.

Continue through the topic

Move to the related lessons or back to the topic page when you need the wider sequence before exam-style practice.