Scurvy basically makes people sick because their body doesn't have the proper vitamins to keep working properly.
It was so deadly before vitamin C curing it was known because vitamin C is necessary for:
-The proper formation of collagen, the protein that helps give the body’s connective tissues structure and stability
-cholesterol and protein metabolism
-iron absorption
-antioxidant action
-wound healing
-creation of neurotransmitters like dopamine and epinephrine
These factors caused things such as gum disease, infections in wounds and anemia.
Wild Rosehip has 426 mg of vitamin C per 100 g. The average reccomended amount of vit. C per day is about 70-110mg. While excessive comsumption isn't good either, it takes a whole lot of vitamin C to get any negative effects, about 2,000mg.