Not all dairy foods contain lactose, or natural milk sugar, and even among those that do, some contain lower levels that may be tolerated by those with milder forms of lactose intolerance. (greenvalleylactosefree.com)
Whey concentrate, along it is rich in protein, also contains a fair amount of fat and sugar (in the form of lactose). (blog.nkdnutrition.com)
It is high in complete proteins, but also contains some fat and sugar in the form of lactose. (blog.nkdnutrition.com)