The effects of milk protein concentrate on the symptoms of osteoarthritis in adults: An exploratory, randomized, double-blind, placebo-controlled trial

Background: Reconstituted hyperimmune milk product has been shown to have anti-inflammatory qualities, prompting further research into its use for the relief of osteoarthritis symptoms. A concentrated form of this milk product, milk protein concentrate (MPC), contains the high-molecular-weight and low-molecular-weight components present in the reconstituted milk product. Objective: The purpose of this exploratory study was to assess the effects of MPC on the symptoms of osteoarthritis in adults. Methods: Patients aged ≥19 years with physician-diagnosed osteoarthritis with daily joint pain, stiffness, and immobility were eligible. This was a prospective, randomized, double-blind, placebo-controlled trial lasting 6 weeks and having 3 treatment arms: MPC 2000 mg BID, glucosamine sulfate 500 mg TID, and placebo. Osteoarthritis symptoms were assessed using the Western Ontario and McMaster Universities (WOMAC) Osteoarthritis Index. Results: Forty-two participants were enrolled (8 men, 34 women; mean age, 59 years [range, 34-86 years]); 35 patients (5 men, 30 women) completed the study. Due to significant baseline differences in 3 (stiffness, activities, and total) of the 4 (pain, stiffness, activities, and total) WOMAC Osteoarthritis Index scores in the placebo group compared with the MPC- and glucosamine sulfate-treated groups (P ≤ 0.05), the results of this study were restricted to the analysis of intragroup performance from baseline to the completion of the study. The results showed significant improvement from baseline to week 6 for the MPC-treated group for all 4 scores (P ≤ 0.005). In the glucosamine sulfate-treated group, a significant improvement was found in stiffness and total WOMAC Osteoarthritis Index scores from baseline to week 6 (P ≤ 0.05 for both) but not in the pain or activities scores. In the placebo group, no significant changes were found in any of the WOMAC Osteoarthritis Index scores. Conclusion: The results of this study indicate that MPC, when given at a dose of 2000 mg BID, was effective in relieving the symptoms of osteoarthritis, including joint pain, joint stiffness, and immobility, in this patient population.