I've taken each one individually and they all cause me to have a very uneven redness across my face after only one or two days of use. This isn't short-lasting like a niacin flush, the redness will last for 4 or 5 days before it starts to fade, and only fades when I discontinue use of the supplement. I've searched all around for answers, but it seems like I'm the only one with this problem. I experienced no other side effects from these supplements other than patchy facial redness. I've never had this problem with any other supplements I've taken, it's been very frustrating. Any theories would be greatly appreciated.