The short answer is yes, they do. At home teeth whitening kits are vastly unregulated, sometimes containing dangerous levels of hydrogen peroxide (some as much as 300 x the recommended amount!) which can cause irreparable damage to your enamel, and gums. Not to mention that the ‘results in 5 minutes’ promise is due to the addition of chlorine dioxide, which you will be familiar with from your days spent learning to swim. That’s right, they use pool cleaner to speed up the process. Which sounds a lot like a one way train to chemical burns, and enamel erosion.
Your gum health is extremely important, causing damage to gum tissue can lead to loss of teeth in the future, which I’m sure we can agree is a much higher price to pay than professional whitening.
Our advice would always be to at least consult your dentists before you go ahead with any kind of treatments which could affect your dental health, especially where DIY whitening is involved!