Techniques like hand washing, wearing gowns, and wearing face masks can help prevent infections from being passed from one person to another. Frequent hand washing remains the most important defense against the spread of unwanted organisms. There are other forms of prevention such as avoiding the use of illicit drugs, using a condom, and having a healthy lifestyle with a balanced diet and regular exercise. Cooking foods well and avoiding foods that have been left outside for a long time is also important.