Most problems we see are in dogs fed homemade diets. Substitution or omission of a single ingredient can cause severe bone diseases despite the best intentions. The most popular idea is that Vitamin C can prevent development of the disease. This theory was proposed because Vitamin C is used to make collagen, one of the major tissues of cartilage, bone and tissues supporting the joint. Even though dogs, unlike people, make their own Vitamin C, it was suggested that a deficiency of Vitamin.
C causes joint laxity seen early in hip dysplasia.
The study which showed some benefit from Vitamin. C supplementation was not done scientifically, and it's results can not be repeated. Perhaps the reasons Vitamin. Unfortunately, research has shown that Vitamin. C adversely affects the dogs' calcium balance, so it may actually increase the risk of some bone diseases, including hip dysplasia.