Researchers found that a modest increase in antioxidants from brightly colored fruits and vegetables -- equivalent to a glass of orange juice a day -- was associated with a lower risk of inflammatory arthritis, such as rheumatoid arthritis.
About Rheumatoid Arthritis
Rheumatoid arthritis (RA) affects about 1% of the U.S. population. It is three times more common in women than in men. It usually occurs in people 20 to 50 years old, but young children and the elderly can also develop rheumatoid arthritis.
Rheumatoid arthritis is a type of inflammatory arthritis that occurs in joints on both sides of the body (such as hands, wrists, or knees). This symmetry helps distinguish rheumatoid arthritis from other types of arthritis.
Antioxidants Come Out Fighting
Oxidation is a normal process that occurs in our bodies. However, it produces harmful by-products called free radicals. Antioxidants help scavenge these damaging substances.
It has long been known that oxidation plays a role in the joint damage seen in rheumatoid arthritis, write the researchers. They add that antioxidants may suppress inflammation by getting rid of the free radicals.
The new study's findings support what researchers have suspected for some time -- that antioxidants in brightly colored fruits and vegetables offer protection against inflammatory arthritis.
The researchers, members of the Arthritis Research Campaign's Epidemiology Unit, in Manchester, England, worked with researchers from the Institute of Public Health at the University of Cambridge.
Vitamin C Also Important
Twenty-five thousand participants aged 45 to 74 were asked to complete a questionnaire regarding their daily diet. Participants were followed over a nine-year period to identify which developed inflammatory arthritis, including RA.
Of the 25,000 participants, 88 developed cases of inflammatory arthritis.
The researchers found an association with certain antioxidants called carotenoids (beta-cryptoxanthin and zeaxanthin) -- which are found in yellow/orange fruits and vegetables -- and a lower chance of developing inflammatory arthritis.
"We found that the average daily beta-cryptoxanthin intake of the 88 patients who developed inflammatory polyarthritis was 40% lower than those who hadn't, and their intake of another carotenoid, zeaxanthin, was 20% lower," researcher Dorothy Pattison, states in a news release.
Those in the top third for beta-cryptoxanthin intake were only half as likely to develop inflammatory arthritis as those in the lowest third, according to Pattison. Vitamin C was also found to be an important factor, she says.