Doctors in one study followed 1,203 men and women for 22 years. Participants reported whether or not they took vitamin C supplements and were at least 40 years old at the start of the study. In the group that began the study without knee osteoarthritis (OA), compared to those who did not use vitamin C, those who consumed vitamin C were 11 percent less likely to develop knee OA. Researchers concluded that vitamin C may help prevent knee OA and may affordably improve public health.
Researchers in another study measured the diets of 719 men and women, aged at least 60. About seven in 10 had knee OA. Doctors found that those who consumed the most vitamin K were least likely to have knee OA and had far fewer signs of damaged or deteriorating joints and cartilage compared to those who consumed less vitamin K.