“Does sugar cause gum inflammation?”

Not directly! It can cause high blood sugar (diabetes) which causes gum inflammation.

Sugar causes inflammation in your entire body when you consume it, so reducing sugar in your diet will reduce the overall inflammation level in your whole system. The major cause of gum inflammation, though, is the reaction your immune system has to bacteria sitting on your teeth at and below the gum line (hence the need to brush more frequently and FLOSS correctly every day).

The sugar can increase the bacteria that will become in the future aggressive on your gums.