Does cooking kill the vitamins in your food?
"Cooking can reduce the nutritional content of veg. It can be a particular problem with vitamin C and the B vitamins and minerals like potassium, because they are water-soluble and so leach out into cooking water. That's fine in soups and stews because you consume the water, but it's a problem if you throw the water away."
"Some veg are more nutritious when cooked because cooking breaks down their cells, which can allow you to absorb more of the nutrients even if some have leached out during cooking. This is true of beta-carotene (a precursor to vitamin A, found in carrots, butternut squash and sweet potatoes) and other carotenoids, such as lycopene, which is found in tomatoes.
Starches and proteins are easier to digest when cooked."
And, of course:
"Cooking also improves the flavour of many veg, and if this makes you more likely to eat them it's worth losing some nutrients!"