Pretty impressed that this genuinely works! Saw a difference after a few days use, not sure what the light really does though?! Once the subtle change occurred my teeth didn't get any whiter. If you are after slight colour lift its fine. One point to make is I never felt like my teeth felt really clean with tights product so would use normal toothpaste and this together.
This toothpaste did nothing for my teeth, they never looked whiter and i used it for 2 weeks, 2 to 3 times a day. I had high expectations for this toothpaste. I would never buy it again and I will stick to normal high street brands.