Are cooked fruits less nutritious?

Earlier on, physiologist Sam Virtue compared the sugar in fruit and doughnuts which motivated Rosemary to get in touch. Chris Smith asked him to cook up an answer...

Sam - I don't know the specific details with the apples but there are certainly some vitamins and minerals that will go away with cooking. And this is why cooking processes which are less stringent perhaps, so for example steaming rather than boiling, they will lead to less of the vitamins and minerals been leached away. So that is certainly the case that you can get a lot of benefits from it but there may be some things you lose.

Chris - So cook with care?

Sam - Indeed!

Chris - But obviously cooking is good because it kills microorganisms and bad for you things that are in there so there's a tossup, I suppose, between the benefits of releasing more calories by cooking and sterilising your food. But, at the same time, you end up with a higher loss of the goods things like vitamin C?

Sam - Absolutely. I think the benefits of cooking historically were vastly greater than perhaps they are now. I mean the certainly certain things that you would absolutely not want the raw even to this day, but a lot of things like fresh fruit and fresh vegetables. We think about going to supermarket and being a beautiful apple well, if you're living through winter and you don't have refrigeration and you've got a bushel of apples then it's a little bit of a different situation maybe 200 years ago.

Chris - There's also cyanide amygdalin which is in the seeds of apples which is not quite so good as the skin you are mentioning Ljiljana. I think I calculated that you'd have to eat about 54 kg of apples before you actually got a fatal dose of amygdalin to wipe out a human but there is still cyanide in the pips so maybe don't eat the core.