OMG this is so adorable! It's almost like an empathetic nod to the comics because if a sorcerer isn't used to casting spells, or if they've been casting them for a long time, then it takes a toll on their body and when Strange started casting spells, he was vomiting for about 3 days. So it's almost like the cloak is helping him eat and stay nourished when he was sick.
When this happened in the movie I leaned over to my dad and was like, "I was waiting for that!" and he was like "you knew that was coming?" and I was like "uhhh yeah I watched the trailer like 17 times"