As others have said, I believe Grapefruit seed extract is the most commonly recommended treatment for candida and has antifungal properties. It is very possible that grape seed extract has similar properties and that is causing the die-off and other problems for you. Personally, I am not a big fan of anti-fungals to treat candida although some people do have success with them (although I don't know if it is the anti-fungal properties or just natural immune stimulation of grape seed extract that is causing you problems). Generally, I feel like a certain diet or supplement is okay if you go through waves of die-off and feeling better in weekly or bi-weekly cycles. If you are in constant die-off for more than two weeks at a time, that is never helpful for the body and you should try something different as you can cause more problems for yourself down the road.