Does dehydrated fruit/veggies retain the same vitamin content once altered?

Question

For instance; Spices? I love Garlic in all forms, but how healthy is Garlic powder compared to fresh raw Garlic? Does the Powder form retain any of the raw Garlic's healthy properties?

Answer 1

If you don't know how it was dehydrated, and didn't do it yourself at home, its best to assume that the fresh form is healthier than the dried form.  

Answer 2

They do, but it depends on the technology used for dehydrating. Certain producers of dehydrated food use old-fashioned technologies that make the food to lose some part of its properties.