Carotenoids Cut Arthritis Risk
Drinking just one glass of freshly squeezed orange juice a day may cut the risk of developing inflammatory forms of arthritis. Researchers from the University of Manchester in the United Kingdom revealed in the American Journal of Clinical Nutrition (August 2005) that some dietary carotenoids, including beta-cryptoxanthin and zeaxanthin, lower the risk of developing arthritis. However, two other dietary carotenoids, lutein and lycopene, did not seem to have the same protective effect against arthritis.
The Study: Do Fruits and Vegetables Reduce Arthritis Risk?
Researchers analyzed data from a study of 25,000 participants to determine if dietary carotenoids impacted arthritis risk. Study participants had completed a diet diary and were followed between 1993 and 2001 to identify new cases of inflammatory polyarthritis, defined as synovitis (inflammation of the lining of the joint) affecting 2 or more joint groups.
The Study Results
Eighty-eight participants were found to have developed arthritis. They were compared to 176 healthy people serving as controls. The mean daily intake of zeaxanthin was 20% lower in the cohort of patients who had developed arthritis than in the controls. The mean daily intake of beta-cryptoxanthin was 40% lower in patients who had developed arthritis than in the control population.
Participants in the top one-third of intake of zeaxanthin and beta-cryptoxanthin were at lower risk of developing inflammatory arthritis than those in the lowest third of intake.
What Is Beta-cryptoxanthin?
Beta-cryptoxanthin is classified as a pro-vitamin A carotenoid. In the body it can be converted to an active form of vitamin A. Vitamin A is recognized as being important for skin and bone health as well as immune function. Beta-cryptoxanthin is contained in yellow or orange fruits and vegetables. Here is a list of yellow and orange fruits and vegetables from www.5aday.org:
- Yellow apples
- Cape Gooseberries
- Yellow figs
- Golden kiwifruit
- Yellow pears
- Yellow watermelon
- Yellow beets
- Butternut squash
- Yellow peppers
- Yellow potatoes
- Yellow summer squash
- Sweet corn
- Sweet potatoes
- Yellow tomatoes
- Yellow winter squash
What Fruits And Vegetables Are Highest In Beta-Cryptoxanthin?
According to NutritionData.com, a comprehensive listing of the 467 foods highest in beta-cryptoxanthin shows:
- peppers, pumpkins, and winter squash as the vegetables with the highest levels of beta-cryptoxanthin per serving.
- persimmons, tangerines, and papayas as the fruits with the highest levels of beta-cryptoxanthin per serving.
What Is Zeaxanthin?
Zeaxanthin is another carotenoid with antioxidant power. According to www.5aday.org, food sources of zeaxanthin include green leafy vegetables and yellow/orange fruits and vegetables.
The research coming out of the University of Manchester supports previous studies which concluded that dietary antioxidants, such as carotenoids beta-cryptoxanthin and zeaxanthin as well as vitamin C, may be associated with reducing the risk of arthritis.
Dietary B-cryptoxanthin and inflammatory polyarthritis: results from a population-based prospective study. American Journal of Clinical Nutrition. August 2005. Eating fruit and vegetables lowers arthritis risk. Ben Wasserman. August 17, 2005.
Dietary B-cryptoxanthin and inflammatory polyarthritis: results from a population-based prospective study. American Journal of Clinical Nutrition. August 2005.
Eating fruit and vegetables lowers arthritis risk. Ben Wasserman. August 17, 2005.