Eat oily fish to keep joints healthy, as well as reduce inflammation, a cause of joint pain and tenderness in people with RA (rheumatoid arthritis)

If you have joint pain from rheumatoid arthritis (RA), eat more fish.

Fatty coldwater fish like salmon and mackerel (and sardines) are good sources of omega-3 fatty acids.

Omega-3s may help keep joints healthy, as well as reduce inflammation, a cause of joint pain and tenderness in people with RA. 

Don't like fish? Try fish oil capsules instead.

Info source for the above is

http://www.m.webmd.com/a-to-z-guides/ss/slideshow-keep-joints-healthy?ecd=wnl_wmh_051714&ctr=wnl-wmh-051714_promo_3&mb=GULHw1r0yczQttMGkoWNR%40HnVev1imbCX2R%2fDNcXcrE%3d

Top plant sources of Omega-3 fatty acids are flaxseeds and walnuts .

The following is from http://www.whfoods.com/genpage.php?tname=nutrient&dbid=84

The following is from 

http://www.drsamuelbledsoe.com/blog/joint-pain-improves-gastric-bypass-surgery/