Lifestyle diseases develop over time due to poor daily habits. Unlike infectious diseases, these conditions stem from unhealthy behaviors such as poor diet, lack of exercise, smoking, and excessive alcohol consumption. Common lifestyle diseases include: Heart Disease Type 2 Diabetes Obesity Certain Cancers Chronic Respiratory Diseases Hypertension (High Blood Pressure) Many of these diseases are interconnected. For instance, obesity can lead to diabetes, which increases the risk of heart disease.