'Whole foods' is one of the commonest term used these days. For all practical purposes it means those foods which (more or less) are in their original form.
Why eat whole foods?
1. More nutrients: Minimal processing ensures that they retain more nutrients.eg. choose Whole wheat flour over refined flour and parboiled rice over basmati.
2. Have more fibre: It is beneficial for the gut health. It normalizes bowel movement. Eat raw salad vegetables like carrots, radish, lettuce, beet root, spring onions etc.
3. Good thermic effect: More energy is needed to digest them than required for refined foods. Have negative calorie vegetables like cucumber, lauki (bottle gourd), turai (ridge gourd), falli (beans), capsicum, tinda etc.
4. Provide satiety at a lower calories: If you eat whole foods they'll fill you up in lesser calories as compared to refined foods. Also they take longer digestion time and thus you feel full for a longer period of time. Therefore they stay in your gut for a longer time preventing hunger pangs. Eg. Oats, wheat/bajra daliya (porriage) etc.
5. Loaded with phytonutrients and antioxidants: Raw fruits and vegetables are loaded with beneficial phytonutrients which protects the body from free radicals.