I've never heard of smart milk, but my nutritionist gave out a recipe for super protein milk that all post bariatric patients used for cooking or drinking after surgery.
But I looked up the smart milk, and this is what I found:
There are 90 calories in 1 cup (8 fl. oz) of Hood Simply Smart Fat-Free Milk. You'd need to walk 25 minutes to burn 90 calories. Visit CalorieKing to see calorie count and nutrient data for all portion sizes.
www.calorieking.com
It's worth mentioning that more than 56% of the nutritional value in 8 oz of smart milk is from carbohydrates. Using words like smart is the way retailers sell things to people like us that aren't nearly as good for us as they want us to believe. Always read the labels. Always exercise moderation and care.