1 Study in 2004. Reported that consumption of chia seeds was associated with ^'ed risk for prostate cancer.
Probably none. The "pop" claim that these wholesome seeds are one more "superfood" should let you know to put your hand over your wallet. If you follow the diet-and-cancer stuff, results are wildly contradictory among studies -- which leads most people (including most physicians) to urge you simply to eat prudently, stay fit, and don't obsess over this stuff. If you like these seeds, enjoy. Don't expect magic.