What are the 3 factors that are the foundation of a healthful eating plan?

1) Details. Anyone can talk in generalities, but what a person wants is detailed instructions and daily menus.
2) Precautions. A good program will inform you of possible hazards, will warn against going overboard, and will ideally include a phone number for emergencies.
3) Goals. A good program will set long-term and interrim goals which you can measure against.
4) Peers. A good program will ideally have you as part of a group, which increases motivation.
5) Moderation. A good program will not be sudden or drastic.
6) Flexibility. A good program will give alternatives and will not be completely rigid. Rigidity equals unnecessary difficulty.
7) Tailoring. A good program will be tailored to you, personally, by a dietician. Since there is no such thing as a universal diet (despite what the paperback bestsellers perenially claim), you'll be best served by a diet that takes you personally into account: what you are and are not able to do, your metabolism, etc.
8) Enjoyment. A good program will not entirely rule out snacks, fat, and sweets, unless you are able to do without. Rather, it can allow for small or reasonable amounts of them as part of its menu and calorie count.