Huel is not a meal replacement shake as a majority of meal replacements are not complete and do not provide all of the essential nutrients. Huel can replace any meal as it is completely balanced with carbohydrate, fats, protein, fibre, vitamins and minerals. Most use it when they don't have time to meticulously plan and prepare a balanced meal and need convenience food, but also don't want to compromise on nutrition. You can find out in more detail why Huel is not a meal replacement here.