Millions of people, worldwide and across the United States are affected by Osteoarthritis. The latest research showed that diets rich in fiber may lower the risk of developing painful knee osteoarthritis.
What is osteoarthritis? It’s known as the most common arthritis also named the “wear and tear,” arthritis, over 30 million U.S. adults are affected by it. Almost 10 percent of men and 18 percent of women aged 60 and over love with symptomatic OA, worldwide. Women over the age of 50 are more likely to develop the condition compared to men.
Annals of the Rheumatic Diseases recently published new research that investigated the link between having a diet rich in fiber and the risk of developing knee OA. The study consisted of a meta-analysis examining two long-term studies on the benefits of a fiber-rich diet. The collaborative study was conducted by researchers from Tufts University in Boston MA and the University of Manchester in the United Kingdom. Dr. Zhaoli Dai, of the Human Nutrition Research Center on Aging and Friedman School of Nutrition Science and Policy at Tufts University was the first author of the study.
For years, studies have concluded that diets rich in fiber provided a variety of health benefits like lowered blood pressure, lower weight, reduced inflammation and even improved blood sugar levels. Fiber sources include nuts, legumes, fruits, whole grains, and non-starchy vegetables.
Studying the link between OA and fiber intake
The new studies included 4,795 participants – Osteoarthritis Initiative (OAI) and 1,267 participants – Framingham Offspring Osteoarthritis Study. Fiber intake was determined by researchers before beginning the study using a food frequency questionnaire. They also assessed incident radiographic OA and symptomatic OA – that is, they used X-ray to determine OA and recorded OA symptoms, the most common of which include knee pain, stiffness, and swelling.
During the study OAI participants were clinically followed ever year for 48 months, and they were evaluated after 9 years as part of the Framingham study. Data was also collected by researcher that may have influenced results like a knee injury, medication, lifestyle, alcohol consumption, and physical exercise.
Low Fiber Intake
During the study, on average, patients consumed 15 grams of fiber daily in the OAI study and 19 grams of fiber daily for the Framingham study.
By the end of the 4 year period – OAI study – a total of 869 participants had OA knee symptoms, 152 showed signs of OA on the X-ray, and 1,964 participants said their knee pain got worse.
At the end of the 9-year period – Framingham study – 143 participants had OA symptoms, and 175 saw signs of OA in their X-rays.
The statistical analysis indicated that higher intake of fiber correlated with a lower risk of OA. Participants were broken up into fourths or quartiles, with the top quartile being compared the the lowest in terms of fiber intake.
Participants who consumed the most fiber had a 30 percent lower risk of OA in the OAI study, and 61 percent lower risk of OA in the Framingham study compared with those who consumed the least amount of fiber.
Furthermore, the study revealed that consuming more fiber in general, as well as more cereal fiber in particular, significantly reduced the risk of the knee pain getting worse. However, as the study is observational, it cannot establish causality.
“Findings from two longitudinal studies consistently showed that higher total fiber intake was related to a lower risk of [symptomatic OA], while the relation to [incident radiographic OA] was unclear.” – Dr. Zhaoli Dai