Non-communicable diseases in humans

Non-communicable diseases (NCDs) are long-term medical conditions that are not caused by infectious agents and cannot be transmitted from person to person. In humans, major NCDs include cardiovascular diseases (like coronary heart disease and stroke), cancers, type 2 diabetes, and chronic respiratory diseases such as asthma. These diseases are the leading cause of death and disability worldwide, accounting for over 70% of all deaths globally. Understanding NCDs is crucial because they are largely preventable through lifestyle modifications, and their management places a significant burden on healthcare systems.

This topic explores the risk factors associated with NCDs, including genetic predisposition, lifestyle choices (diet, physical activity, smoking, alcohol consumption), and environmental factors. You will learn how these risk factors interact to increase the likelihood of developing specific diseases. For example, a diet high in saturated fats and low in fibre can lead to obesity and high blood pressure, which are major risk factors for cardiovascular disease and type 2 diabetes. The topic also covers the concept of correlation and causation, helping you critically evaluate evidence linking risk factors to disease.

In the WJEC GCSE Biology curriculum, this topic builds on your understanding of the human body systems, particularly the circulatory and respiratory systems, and introduces the idea of disease prevention at a population level. You will also explore how lifestyle choices can affect the function of organs and cells, leading to disease. Mastery of this topic is essential for understanding public health strategies and the importance of personal responsibility in maintaining health.