The Zone Diet was developed by biotechnology researcher Barry Sears. Central to the Zone Diet is insulin control, because properly controlled and maintained insulin levels can lead to fat loss, decreased risk of cardiovascular disease, and greater mental acuity. Insulin control through the Zone Diet involves eating meals with protein and carbohydrates balanced in a specific ratio. Most of the carbohydrates in the Zone Diet come from fruits and vegetables, and intake of starchy foods, such as bread, pasta, and rice, is very limited.
Note that regardless of the type of food plan, calories that are consumed in excess of what is burned through daily activity, metabolic processes, and exercise, will be stored as fat.
In addition to following a balanced food plan, using the Zone Diet also involves taking fish oil supplements. The long-chain omega-3 fatty acids supplied in fish oil are a "key factor" in controlling insulin levels, according to Dr Sears.
Two of these beneficial fatty acids, DHA and EPA, have been linked to reduction of cancer, heart disease, arthritis, and certain chronic and degenerative diseases.