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, and explain the effect of lifestyle factors including diet, alcohol and smoking on the incidence of non-communicable diseases at local, national and global levels. • Risk factors are linked to an increased rate of a disease. They can be: aspects of a person's lifestyle; substances in the person's body or environment. A causal mechanism has been proven for some risk factors, but not in others. The effects of diet, smoking and exercise on cardiovascular disease. Obesity as a risk factor for Type 2 diabetes. The effect of alcohol on the liver and brain function. The effect of smoking on lung disease and lung cancer. The effects of smoking and alcohol on unborn babies. Carcinogens, including ionising radiation, as risk factors in cancer. Many diseases are caused by the interaction of a number of factors.