Article: Nutrients are most plentiful in fruits and vegetables that have just been picked. The longer you wait to eat your food, the more nutrient loss will have occurred.  Only buy as much as you will use in a few days. It is better to shop more often and have fresher food options. Shop at markets that offer the freshest food. In season, you may be able to buy directly from farmers or at farmers’ markets. Cooking vegetables can reduce the amount of vitamin C they contain, though it can also increase other valuable nutrients, such as lycopene. Broccoli, watercress, and garlic are all generally better raw than cooked. Moderation and balance are the keys. Raw broccoli contains sulforaphane, a potentially protective compound, and raw carrots contain polyphenols, another protective group of chemicals. Cooking these vegetables destroys these compounds, but replaces them with other beneficial substances including indole and carotenoid. Air, water and heat all attack vitamins starting at the surface of the produce. Vegetables cut into large pieces will retain more nutrients in cooking than small pieces. If you need smaller, bite-size pieces, you can always cut them smaller prior to serving. Avoid fruits that were picked green. Tomatoes ripened outdoor on the vine can have twice as much vitamin C as greenhouse tomatoes, for example.

What is a summary?
Eat fresh foods. Include raw food in your diet. Reduce surface exposure. Choose fruits ripened in the sun.