"But try to take it, John, for my sake."
Then for her sake you say she can leave it on the chair, and perhaps you will just taste it. As soon as she has gone you devour that partridge, and when she comes back she has the sense to say:
"Why, you have scarcely eaten anything. What could you take for supper?"
You say you can take nothing, but if she likes she can cook a large sole, only you won't be able to touch it.
"But try to take it, John, for my sake"
The chances are that he won't understand your case