***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: Objectives To investigate the effects of a Mediterranean type diet on patients with osteoarthritis ( OA ) . Participants Ninety-nine volunteers with OA ( aged 31 - 90 years ) completed the study ( 83 % female ) . Setting Southeast of Engl and , UK . Design Participants were r and omly allocated to the dietary intervention ( DIET , n = 50 ) or control ( CON , n = 49 ) . The DIET group were asked to follow a Mediterranean type diet for 16 weeks whereas the CON group were asked to follow their normal diet . Measurements All participants completed an Arthritis Impact Measurement Scale ( AIMS 2 ) pre- , mid- and post- study period . A subset of participants attended a clinic at the start and end of the study for assessment of joint range of motion , ROM ( DIET = 33 , CON = 28 ) , and to provide blood sample s ( DIET = 29 , CON = 25 ) for biomarker analysis ( including serum cartilage oligomeric matrix protein ( sCOMP ) ( a marker of cartilage degradation ) and a panel of other relevant biomarkers including pro- and anti-inflammatory cytokines ) . Results There were no differences between groups in the response of any AIMS 2 components and most biomarkers ( p > 0.05 ) , except the pro-inflammatory cytokine IL-1α , which decreased in the DIET group ( ~47 % , p = 0.010 ) . sCOMP decreased in the DIET group by 1 U/L ( ~8 % , p = 0.014 ) . There was a significant improvement in knee flexion and hip rotation ROM in the DIET group ( p < 0.05 ) . Conclusions The average reduction in sCOMP in the DIET group ( 1 U/L ) represents a meaningful change , but the longer term effects require further study The unsaponifiable fraction of  olive oil  from  unripe fruits of Olea europaea at different stages of maturation ( from 20 to 32 weeks after flowering ) was analyzed by gas chromatography-mass spectrometry in order to select the time associated to the unsaponifiable fraction with the maximal yield in bioactive constituents . According to quantitative gas chromatography-mass spectrometry analysis , the unsaponifiable fraction ( 2.46 % of the total oil ) from olive fruits at the 22nd week was found to contain the maximal yield in anti-inflammatory constituents . Its composition was lanosterol ( 2.60 mg/g oil ) , stigmasterol ( 2.15 ) , cycloartanol acetate ( 2.04 ) , stigmastan-3,5-diene ( 2.01 ) , obtusifoliol ( 1.93 ) , cholesta-4,6-dien-3-one ( 1.42 ) , α-amyrin ( 1.42 ) , α-tocopherol ( 1.32 ) , squalene ( 1.02 ) , β-amyrin ( 0.57 ) , and β-sitosterol ( 0.22 ) . At later times , there was a decrease in the quantitative unsaponifiable fraction yield and a qualitative shift in the bioactive constituents . The 22nd week unsaponifiable fraction was subsequently incorporated into a topical preparation to be utilized for a small pilot clinical study in five patients affected by osteoarthrosis . According to clinical observation , the application of the ointment ( three times daily for three weeks ) attenuated h and and knee joint inflammatory features in all patients and was not associated to any adverse reactions Hydroxytyrosol is mainly found in olive leaves after hydrolysis of oleuropein and has anti-oxidant , anti-bacterial , and anti-inflammatory properties . The aim of this study was to investigate the effect of hydroxytyrosol for alleviating the pain in patients with gonarthrosis . We conducted a double-blind clinical trial in which hydroxytyrosol or placebo was administered to adult patients with gonarthrosis for 4 weeks . The group administered hydroxytyrosol showed significant improvement in the Japanese Orthopedic Association score ( pain measurement index ) and the visual analog scale score compared to the placebo group O steoarthritis ( OA ) is the most common type of arthritis , and the knee is the most common site of symptomatic OA . Knee OA is responsible for a higher incidence of disability than any other long-term conditions . Topical therapies present a therapeutic option for OA pain management .  Nonsteroidal antiinflammatory drugs ( NSAIDs ) , salicylates , and capsaicin are currently the main topical therapies available . There is a need for safe and effective drugs for patients who do not respond well to conventional medical therapy . Indeed , such patients are turning increasingly to complementary/alternative medicines . One of the traditional methods for management of knee pain in some rural area of Iran is application of topical olive oil , as reported by Avicenna in his 10th-century book Canon of Medicine . Although the composition of olive oil is complex , the major groups of compounds thought to contribute to its observed health benefits include oleic acid , phenolics , and squalene , all of which have been reported to inhibit oxidative stress . Research ers reported beneficial effects of olive oil on rheumatoid arthritis after oral consumption . In 2005 , (j)-oleocanthal , the dialdehydic form of (j)-deacetoxy-ligstroside aglycone present in freshly pressed extra virgin olive oil , was shown to have properties of an NSAID . Although topical virgin olive oil is traditionally used in Iran in treating knee pain as an herbal medication , our survey did not find any scientific evaluation of its efficacy . Accordingly , we conducted a pilot prospect i ve , comparative , r and omized , doubleblinded trial of topical virgin olive oil therapy versus piroxicam gel in the treatment of knee OA . The report was prepared as recommended by the CONSORT statement and its elaboration on herbal interventions IMPORTANCE Knee osteoarthritis ( OA ) , a common cause of chronic pain and disability , has biomechanical and inflammatory origins and is exacerbated by obesity . OBJECTIVE To determine whether a ≥10 % reduction in body weight induced by diet , with or without exercise , would improve mechanistic and clinical outcomes more than exercise alone . DESIGN , SETTING , AND PARTICIPANTS Single-blind , 18-month , r and omized clinical trial at Wake Forest University between July 2006 and April 2011 . The diet and exercise interventions were center-based with options for the exercise groups to transition to a home-based program . Participants were 454 overweight and obese older community-dwelling adults ( age ≥55 years with body mass index of 27 - 41 ) with pain and radiographic knee OA . INTERVENTIONS Intensive diet-induced weight loss plus exercise , intensive diet-induced weight loss , or exercise . MAIN OUTCOMES AND MEASURES Mechanistic primary outcomes : knee joint compressive force and plasma IL-6 levels ; secondary clinical outcomes : self-reported pain ( range , 0 - 20 ) , function ( range , 0 - 68 ) , mobility , and health-related quality of life ( range , 0 - 100 ) . RESULTS Three hundred ninety-nine participants ( 88 % ) completed the study . Mean weight loss for diet + exercise participants was 10.6 kg ( 11.4 % ) ; for the diet group , 8.9 kg ( 9.5 % ) ; and for the exercise group , 1.8 kg ( 2.0 % ) . After 18 months , knee compressive forces were lower in diet participants ( mean , 2487 N ; 95 % CI , 2393 to 2581 ) compared with exercise participants ( 2687 N ; 95 % CI , 2590 to 2784 , pairwise difference [Δ](exercise vs diet ) = 200 N ; 95 % CI , 55 to 345 ; P = .007 ) . Concentrations of IL-6 were lower in diet + exercise ( 2.7 pg/mL ; 95 % CI , 2.5 to 3.0 ) and diet participants ( 2.7 pg/mL ; 95 % CI , 2.4 to 3.0 ) compared with exercise participants ( 3.1 pg/mL ; 95 % CI , 2.9 to 3.4 ; Δ(exercise vs diet + exercise ) = 0.39 pg/mL ; 95 % CI , -0.03 to 0.81 ; P = .007 ; Δ(exercise vs diet ) = 0.43 pg/mL ; 95 % CI , 0.01 to 0.85 , P = .006 ) . The diet + exercise group had less pain ( 3.6 ; 95 % CI , 3.2 to 4.1 ) and better function ( 14.1 ; 95 % CI , 12.6 to 15.6 ) than both the diet group ( 4.8 ; 95 % CI , 4.3 to 5.2 ) and exercise group ( 4.7 ; 95 % CI , 4.2 to 5.1 , Δ(exercise vs diet + exercise ) = 1.02 ; 95 % CI , 0.33 to 1.71 ; P(pain ) = .004 ; 18.4 ; 95 % CI , 16.9 to 19.9 ; Δ(exercise vs diet + exercise ) , 4.29 ; 95 % CI , 2.07 to 6.50 ; P(function ) < .001 ) . The diet + exercise group ( 44.7 ; 95 % CI , 43.4 to 46.0 ) also had better physical health-related quality of life scores than the exercise group ( 41.9 ; 95 % CI , 40.5 to 43.2 ; Δ(exercise vs diet + exercise ) = -2.81 ; 95 % CI , -4.76 to -0.86 ; P = .005 ) . CONCLUSIONS AND RELEVANCE Among overweight and obese adults with knee OA , after 18 months , participants in the diet + exercise and diet groups had more weight loss and greater reductions in IL-6 levels than those in the exercise group ; those in the diet group had greater reductions in knee compressive force than those in the exercise group . TRIAL REGISTRATION clinical trials.gov Identifier : NCT00381290 
    Output:
    
The prevalence of OA was lower in participants with a higher adherence to a Mediterranean diet .
Biomarkers of inflammation and cartilage degradation related to OA were also analyzed and significant differences were detected only for IL1-α , which decreased in the MD group .
In conclusion , the three studies included in this systematic review demonstrated some relation between osteoarthritis and a Mediterranean diet .