In a review of 68 existing studies, researchers found that weight reduction, in particular, can help to reduce the progression of osteoarthritis symptoms. They also found that lipid-modifying diets may contribute to reduced symptoms, though the evidence for that outcome was more sparse.
Photo © iStockphoto.com/Raycat
A new review1 published in Rheumatology (Oxford) suggests that weight management and proper diet and nutrition may play a role in managing symptoms of osteoarthritis. In a review of 68 existing studies, researchers found that weight reduction, in particular, can help to reduce the progression of osteoarthritis symptoms. They also found that lipid-modifying diets may contribute to reduced symptoms, though the evidence for that outcome was more sparse.
Osteoarthritis is the most prevalent form of arthritis. As the global population ages, osteoarthritis is likely to become an increasingly common concern; by the year 2050, as many as 130 million people will suffer from osteoarthritis, the researchers write. Current treatments for osteoarthritis are somewhat limited, although it is believed that weight reduction, particularly for obese or overweight patients with osteoarthritis, is a key strategy for attenuating osteoarthritis symptoms. Thus, the researchers posited that diet may also have an impact on the severity or progression of arthritic symptoms.
Between October 2015 and May 2017, researchers searched the PubMed database for articles on the effects of obesity, as well as polyunsaturated fatty acids, cholesterol, and vitamins A, C, D, E, and K, on risk or progression of osteoarthritis. The researchers included studies published within the last 10 years, but also included studies that dated back to 2000 for vitamins A, C, D, and E, and to 1995 for vitamin K. Among the 1,190 studies consulted were human studies and randomized, controlled trials. The final list of articles included 68 studies.
Studies focusing on obesity and osteoarthritis demonstrated that obesity increases strain on weight-bearing joints; consequently, obese individuals are at a higher risk for knee arthroplasty. Further, a large Netherlands Epidemiology of Obesity cohort study showed that a higher fat percentage was associated with hand osteoarthritis. Obesity was also linked to a higher risk for type 2 diabetes. Type 2 diabetes, in turn, was found in one study to be an independent risk factor for severe osteoarthritis. In sum, weight reduction in overweight or obese osteoarthritis patients reduced joint impact, improved inflammatory adipokine secretion patterns, and positively affected metabolic-risk profile.
Regarding polyunsaturated fatty acids, the researchers found that there may be a connection between fish oil supplementation and osteoarthritic pain reduction. Specifically, the researchers noted “a strong association between osteoarthritis and raised serum cholesterol.” Polyunsaturated fatty acids are known to help lower cholesterol; thus, a diet higher in polyunsaturated fatty acids may help to reduce some symptoms of osteoarthritis. In addition, they write, fish oil is known to possess heart-health benefits, which “may be relevant to this population owing to the association of [osteoarthritis] with metabolic syndrome.”
While the researchers did not find any conclusive data on vitamin D deficiency as a causal factor for osteoarthritis, there do appear to be benefits of vitamin D supplementation for muscle strength, which can help obese patients with osteoarthritis lose weight through exercise. This, in turn, could help to attenuate some of the symptoms of osteoarthritis.
Likewise, the studies included in this review did not provide adequate data to determine a connection between vitamin K deficiency and osteoarthritis. However, the authors note, “the essential role of vitamin K in bone and cartilage health is incontrovertible.”
One of the key limitations of the current review is that the evidence consulted was largely based on observational studies, note the authors. Nevertheless, excess adipose tissue did appear to be a significant factor in the severity of osteoarthritis symptoms. Thus, they concluded that “dietary modification to achieve weight reduction where appropriate, together with increased physical activity, are the strongest evidence-based recommendations,” to reducing the symptoms or progression of osteoarthritis symptoms.
Finally, although evidence for the benefit of dietary-lipid modification and lowering of serum cholesterol on osteoarthritis is lacking, the dietary recommendations proposed in this review may provide, at minimum, a benefit for subjects’ metabolic health. “While vitamin/micronutrient data are limited,” the researchers state, “there is a plausible role for these nutrients in preventing/slowing osteoarthritis, though at what intake levels remains to be seen.”
1. Thomas S et al., “What is the evidence for a role for diet and nutrition in osteoarthritis?” Rheumatology. Published online April 17, 2018.