You should look for trans fat and saturated fat content if it is over 2%it's not healthy, you should also look for artificial flavor which is not good for you and added color wich unless organic is not good for you. I hope this helps!!!
The best answer for this question would be to talk to the cashier, in situations like these the customer is always right and knows exactly what they want, and if that doesn't work out ask the manager so he can get the correct coffee he wishes for.