Can antioxidants really help lower risk of cancers?

I always hear about antioxidants being extremely beneficial to your body against diseases. I read it online, I see it from Dr. Oz, etc. but when I google, it seems that a lot of the studies are inconclusive. So is it or is it not?

Also, do you guys actually believe there have been better treatments than chemotherapy out there? Such as eating a lot better, using certain herbs, baking soda, etc? I watched a documentary called The Hidden Cure for Cancer and it mentioned all these people that have cured people’s cancers and had been arrested or shot down by the medical industry. Okay, so they didn’t CURE cancer cuz I think their stats weren’t over 50% but it was a better survival rate than chemo.