It is and image of a cup with a lid and a straw filled with some kind of liquid. There is a line going through the cup like no sugary drinks are allowed.
This No Sugar icon is made in Material Design style
developed by Google. This style is based on extremely simplified shapes, thin two-pixel lines, and is optimized for 24x24 px. Unlike other vector icon packs that have merely hundreds of icons, this icon pack contains 5,500 icons, all in the same style and quality.