As part of "Diets that Work", I recommend The Mediterranean Diet as described by the Mayo Clinic.

The Mediterranean diet emphasizes:

• Eating primarily plant-based foods, such as fruits and vegetables, whole grains, legumes and nuts
• Replacing butter with healthy fats such as olive oil and canola oil
• Using herbs and spices instead of salt to flavor foods
• Limiting red meat to no more than a few times a month
• Eating fish and poultry at least twice a week
• Drinking red wine in moderation (optional)

Feedback indicates that this diet is safe and results in weight loss in a short amount of time, as well as being sustainable over an extended period of time.

Source: Mayo Clinic, Mediterranean diet: A heart-healthy eating plan