Another of these foods that has been researched in recent years is tart red cherries.
A study conducted in 2003 by the University of California, Davis was the first to test for key inflammatory indicators, called markers, in blood samples from healthy people. Prior studies had analyzed sweet and tart cherry extracts in test tubes.
The primary focus of the investigation was , which results from the body’s inability to excrete uric acid. This excess uric acid forms crystals which settle in joints, primarily the big toe, and cause severe pain. The precursor of these crystals is urate and it was the blood plasma urate level that was being measured. They also measured the amount of urate removed from the body through urine.
There were 10 women is this study who were 22 to 40 years of age. They were given instructions not to eat strawberries or other fruits and vegetables, or drink red wine or tea for 2 days prior to the test because these foods are high in antioxidants and the researchers did not want these to interfere with the results of the cherry analysis.
On the day of the test they were given 45 pitted fresh cherries for breakfast. Blood and urine samples were then taken at 1-1/2, 3 and 5 hours afterward.
The results showed that their plasma urate levels were significantly reduced over the 5 hours following the breakfast. Likewise, the level of urate removed through the urine increased over those 5 hours.
There were other inflammation markers the researchers looked for. These include C-reactive protein (CRP), nitric oxide (NO) and tumor necrosis factor alpha (TNF).
CRP is produced in the liver and increases rapidly during inflammation. Normal levels are extremely low. TNF alpha is produced by the body when fighting tumors and may increase inflammation. NO is a biochemical that is believed to cause damage to arthritic joints.
Results from the blood draw 3 hours after eating the cherries showed that levels of CRP and NO were lower than at the start of the test. However, the TNF alpha level was unchanged.
A follow up study, which included 18 women and 2 men, was conducted over a longer period. This group was asked to consume the same amount of cherries as the earlier group, but throughout the day for 28 consecutive days.
This study reported a 25% decrease in CRP by the 28th day and an 18% decrease in NO after 21 days. The report concluded that, “supplementing the diets of healthy men and women with cherries reduced the serum/plasma concentrations of some markers of inflammation, whereas circulating concentrations of many other markers of inflammation, lipids and their subfractions, and particle sizes were not affected. The anti-inflammatory effects of cherries may be of clinical significance and should be investigated in further studies. “