I was just reading about how it is the enzymes in fruits and veggies that help heal the body during a fast from other foods; by allowing the tissues to rest adn the immune system to do its job fully. This book stated that when we eat food without enzymes the white blood cells are increased to help out with digestion, when these white cells are taken away from doing their job the immune system is weakened. Perhaps your immune system was too busy with the oil to be seeking out and destroying infected and worn out cells. ?
(The book went on to say that those with food allergies can rid their allergies by consuming plant enzymes along with their food, this calms down the immune system reactions.)
Again just me thinking out loud, I am no scientist just a dietitian, who likes to ponder WHY.