The 3 Day Diet is basically a calorie restriction diet that users follow strictly for 3 days followed by 4-5 days of "normal eating". The diet can then be started again. There is no mention of excercise within the plan and much of the advertised "10 pound weight loss" is down to fluid loss rather than fat.
The 3 Day Diet meal plan:
Day 1
Breakfast
Black coffee or tea, with 1-2 packets of sweetener
1/2 grapefruit or juice
1 piece toast with 1 tablespoon peanut butter
Lunch
1/2 cup tuna
1 piece toast
Black coffee or tea, with 1-2 packets of sweetener
Dinner
3 ounces any lean meat or chicken
1 cup green beans
1 cup carrots
1 apple
1 cup regular vanilla ice cream
Day 2
Breakfast
Black coffee or tea, with 1-2 packets of sweetener
1 egg
1/2 banana
1 piece toast
Lunch
1 cup cottage cheese or tuna
8 regular saltine crackers
Dinner
2 beef franks
1 cup broccoli or cabbage
1/2 cup carrots
1/2 banana
1/2 cup regular vanilla ice cream
Day 3
Breakfast
Black coffee or tea, with 1-2 packets of sweetener
5 regular saltine crackers
1 ounce cheddar cheese
1 apple
Lunch
Black coffee or tea, with 1-2 packets of sweetener
1 boiled egg
1 piece toast
Dinner
1 cup tuna
1 cup carrots
1 cup cauliflower
1 cup melon
1/2 cup regular vanilla ice cream
In addition to the strict eating plan, dieters drink 4 cups of water or noncaloric drinks daily.