But, Michelle Obama is keeping things really real and was recently seen promoting her line of healthy kids beverages, PLEZi ...

she walks the walk -- and the drinks she was promoting at this seemingly casual trip to Costco back that up. Just look at the difference between a Plezi Fizz soda and a similar serving of Coke.

Costco shoppers in Livermore, California were surprised on Tuesday to find the author and children's health advocate standing at the end of an aisle holding up a case of PLEZi FiZZ, a soft drink ...

Holding up a case of Plezi Fizz, a beverage for kids ... and apple smash. RELATED: Costco Shopper's Email to CEO About 'Disgusting' Product Got a Wild Response Shake and Stir Co., mobile ...