Soft drink companies must engage and educate the public about their diversifying range of products even after they introduce calorie amounts on vending machines.

Major soda companies such as Coca-Cola and PepsiCo should view the “Calories Count” vending program as only one step in a transparent relationship with increasingly health-conscious consumers and public officials, say industry leaders.

“These efforts are all great first steps,” said Rich Goldblatt, SVP and director of the Better4You practice at M Booth. “Food companies also should be ...