I believe that the following 3 articles have discussed protein intake to the point of ridiculousness.
Dear Mom and Dad
There are subtleties involved here -- there's a different between protein requirements and optimal intake -- there's a difference between protein's effect on building muscle and on accelerating protein turnover -- there's a difference between protein for ergogenic benefit and protein for metabolic advantage.
So if your prof says "you don't need more protein" you can ask "for what - growth and development? building muscle? accelerating protein turnover? muscle preservation on a low carb diet? increased thermic effect of feeding?"
Also ask: "at what level are you suggesting is adequate for each of the above?"
Also ask: "what if someone is only eating 2 meals a day?"
There are a million "protein issues" that need discussion. Dont oversimplify or allow her to either.
And, for the record, protein powder IS NOT necessary. Most people can get all they need to boost performance, improve body comp, build muscle from whole food.
But they don't.
So they either have to eat more whole food or take some supplements to make up for what they're missing from whole food.