Our problem is that, within our culture, we can't! As english-nation's answer suggested - by talking about 'metaphor' - Yin/Yang for us is just about balance. You have the concept of 'Yin food' (with no metaphor), but we don't. Yin and Yang can be used separately to qualify nouns in Chinese; in my earlier Tai Chi classes I was confused by the concept of 'your Yin hand' (I'm still not sure - maybe it changes from left to right depending on what you're doing!)
So the nearest we can get is 'You should eat a balanced diet'. Maybe this is quite close in meaning, if Yin and Yang relate in some way to foods containing carbohydrates, meat, vegetables, dairy products, and fats (of various kinds) - I've probably got that wrong, but do a Google search for '5 a day'. I don't know.
For example, for us potatoes and spaghetti are both in the carbohydrate group along with rice, but for you one might be Yin and another Yang. (This is just an example; I'm just saying that you might divide foods up differently from the way we do. The only way to be sure would be if you posted lists of foods divided into your categories.)
'A balanced diet' might be the nearest you'll get, but be aware that interpretations of what 'balanced' means differ between cultures. ;-)
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