More vitamin c after cooking?

How resilient is Vitamin D Can it be destroyed easily by the cooking process or when poor storage is used?

• Answer:

  Vitamin D is actually a group of hormone-like chemicals called steroid alcohols. The vitamin group is fat-soluble and quite stable: it won't be lost in storage, cooking or processing. The skin is able to manufacture vitamin D - up to 10 IU per square centimetre, depending on the level of pigmentation (darker skins produce less) and the amount of air pollution (pollution absorbs ultraviolet light, preventing so much of it penetrating the skin and thus enabling the production of the vitamin). Source: http://www.independentliving.co.uk/vitamin3.html