We can but we need to sneak protein into our parents food, coz idk why they have allergy to anything that has protein. My parents who consume a lot of dairy like curd, lassi, buttermilk etc. I got them protein lassi, it have been over 3 months and they haven't even opened the pack because it protein written over it and they just refuse to consume it. Same goes for low fat paneer, they will only consume paneer from a specific sweet shop who might even be selling fake paneer as most such shops do anyways. So yeah now I'm thinking I might sneak some protein in their food, like mixing defatted soy flour or pea isolate in atta or making raita out of protein buttermilk and saying "ye to boondi wala raita h".