Here is the Harvard medical school guide to the best diet:
1. Eat variety of foods. Since no single food is perfect, you need a balanced mix of foods to get all the nutrients you need.
2. Eat more vegetable products and fewer animal products.
3. Eat more fresh and homemade foods and fewer processed foods.
4. Eat less fat and cholesterol. Fat should provide 20 to 30 percent of the calories in your diet. Restrict saturated fat to less than one-third of your total fat intake by reducing your consumption of meat, whole dairy products, and the skin of poultry. Limit your intake of trans fatty acids by reducing your consumption of partially hydrogenated vegetable oils found in stick margarine, fried foods, and many commercially baked goods. Favor mono unsaturated and omega-3 fats that are found in olive oil, fish, nuts. Restrict your cholesterol intake to less than 300 milligrams per day by limiting your intake of egg yolks.
5. Eat at least 25 to 30 grams of fiber per day by increasing your consumption of bran cereal, whole grains, vegetables, and fruit. Favor oats, barley, beans, and other sources of soluble fiber.
6. Eat more complex carbohydrates and less sugar by eating more grain products, starchy vegetables, and pasta. Complex carbohydrates should provide 55 to 65 percent of the calories in your diet. Favor foods with low glycemic index.
7. Eat protein in moderation. Protein should provide 10 to 15 percent of the calories in your diet. Favor fish, legumes, and skinless poultry as protein sources.
8. Restrict your sodium intake to less than 2,400 milligrams per day, particularly if your blood pressure is elevated or high, by reducing your use of table salt and processed foods such as canned soup and juices, luncheon meats, condiments, frozen dinners, cheese, tomato sauce, and snack foods.
9. Eat more potassium-rich foods, such as citrus fruits, bananas, and other fruits and vegetables.
10. Eat more grain products, especially whole grain products, aiming for six or more servings per day.
11. Eat more vegetables and legumes, especially deep green and yellow-orange vegetables. Aim for at least three to five servings of vegetables each day.
12. Eat more fruits, aiming for at least two to four servings each day.
13. Eat more fish, aiming for at least two to four servings per week.
14. If you choose to eat red meats, reduce your intake to about two 4-ounce servings per week. Avoid “prime” and other fatty meats, processed meets and liver.
15. Eat chicken and turkey in moderation, always removing the skin.
16. Eat eggs sparingly; aim for an average of no more than one egg yolk per day, including those used in cooking and baking.
17. Use vegetable oils in moderation, favoring olive oil. Reduce your intake of partially hydrogenated vegetable oils, palm oil, coconut milk, and cocoa butter.
18. If you can use alcohol safely and choose to drink, drink sparingly. Do not average more than two drinks per day.
19. Adjust your caloric intake and exercise level to maintain a desirable body weight. If you need to loose weight, aim for gradual weight loss by reducing your intake of calories and increasing your amount of exercise.
20. Avoid fad diets and extreme or unconventional nutritional schemes. If it is too good to be true, it’s not true.