Patients with knee osteoarthritis who received vitamin D supplementation did not have a significant difference in knee pain or cartilage volume loss compared to patients who received a placebo, according to Study: Vitamin D Doesnt Help Knee Arthritis Other Hearst Subscriptions.

"Despite its impact, there are no medical treatments established to influence the course of the disease,” the researchers wrote. “Some studies have suggested that vitamin D may protect against structural progression.”

For this study, 146 people with knee osteoarthritis, with an average age of 62, were randomly assigned to get a placebo or vitamin D3 daily for two years. The vitamin D dose started at 2,000 IU per day and was adjusted until blood levels of vitamin D rose to 36 ng/mL. Pain and cartilage volume loss was measured periodically throughout the study.

Blood levels of vitamin D rose significantly more among those who took the vitamin D supplements; while 61.3% of those taking the supplement reached the blood level goal, only 8.3% of those who took the placebo had blood levels of vitamin D that high. Nonetheless, after two years, there were no significant differences in pain and cartilages loss between the two groups.

"The results of this trial together with recent observational data indicate that vitamin D does not have a major effect on knee [osteoarthritis] symptoms or progression," the researchers concluded.

Most sports medicine professionals agree that running isn't a significant risk factor for developing knee osteoarthritis. Some physicians say that moderate running can help to alleviate symptoms for people with mild knee osteoarthritis.

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Scott Douglas

Scott is a veteran running, fitness, and health journalist who has held senior editorial positions at Runner’s World and Running Times. Much of his writing translates sport science research and elite best practices into practical guidance for everyday athletes. He is the author or coauthor of several running books, including Benefits of Running for Mental Health, Advanced Marathoning, and Other Hearst Subscriptions. The Relationship Between Running and Anxiety Slate, The Atlantic, the Washington Post, and other members of the sedentary media. His lifetime running odometer is past 110,000 miles, but he’s as much in love as ever.