I've taken NOW brand for other things like Vitamin D and they seem pretty legitimate. Though the reviews here seem like the side effects are horrible & counter

I've taken NOW brand for other things like Vitamin D and they seem pretty legitimate. Though the reviews here seem like the side effects are horrible & counter the the purpose. https://www.amazon.com/NOW-Supplements-Nicotinamide-Dinucleotide-D-Ribose/dp/B0030GXSVE/ https://www.amazon.com/NOW-Supplements-Nicotinamide-Dinucleo...