Sour berries or fruits have certain vitamins, that protect us from diseases. A handful of cranberries per day will not harm you. And you will only need a couple of grams of freeze-dried ones.
Freeze-dried food products are good snacks for people that are in a hurry, exercising and living a healthy life. This replaces sweets for children. It is especially good for vegans and vegetarians because it is not heat-treated.