The skin DRINKS in what it comes in contact with, so if your applying anything, the oil seems a better choice. Is it needed? No, your skin desires to breathe air and expel off wasted metals and toxins. Applying anything other than clean water will force he skin to respond.
The 14-21 day orange juice fasting is a GREAT START, but i suggest it takes 30+ days to clean up enough to allow the skin to cleanse and this is why I suggest 40 days for skin issues and it eliminates the need for lotions/potions, because after 40 days you have new clean skin again.