The curcumin arthritis studies have a major flaw: Neither included a placebo, or control group, says rheumatologist David Felson, who directs an arthritis research team at Boston University School of Medicine.

WSJ: Flavor in Curry Favored by Some for Joint Pain

One such, carried out in the British city of Durham, was controversial in that it was funded by a maker of children's omega-3 supplements and did not include a control group being given a placebo.

ECONOMIST: Eat your way to a better brain

The result was that three-quarters of the treated group did not relapse into depression: a success rate twice as high as that of the 20 patients in the control group, who received a placebo regimen.

ECONOMIST: People, like all living things, are four dimensional