The 7-11 Double Big Gulp holds about twice the amount of fluid than the average adult human’s stomach. The average adult human’s stomach can hold comfortably about 32 ounces at any given time. The Double Big Gulp holds about 64 ounces of soda or Slurpee. On top of this the average Double Big Gulp contains about 60 teaspoons of sugar. Are you sure you really want to supersize???