2. Cutting veg further reduces nutrients by exposing them to air - nutrients are easily destroyed by oxygen. The ideal method is to pick, cut and cook or just eat your veg as soon as possible after it has been cut. If you need to cut your veg prior to cooking it then covering it in a small amount of cold water will slow down oxidation. Water will leach some of the nutrients out, but possibly less than if you cut and left your veg exposed to air.
3. The way you cook your veg has a great impact on the nutrients left in them at the end. Boiling leaches out lots of nutrients, much more than steaming - but if you cook your veg in a stew and eat the liquid that they were cooked in then you will still consume all but the heat sensitive nutrients, which are destroyed by cooking of any method.
4. If being able to prepare veg in advance ensures that you eat more of it then you will be getting more nutrients anyway - even if some are lost through cutting and keeping in water.
5. If you are concerned about getting enough nutrients from your veg, try to eat some sprouted seeds, nuts and grains every day, add some sea vegetables (seaweed) and some baby salad greens (mustard and cress, baby beet shoot, radish shoots - can be grown even by children on your windowsill). This way you will pack in the maximum amount of nutrient in the smallest amount of veg and happily continue preparing your other veg in any way that suits your lifestyle.
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