The animal fats found in meat, milk, and eggs contain far more arachidonic acid than vegetable fats. Arachidonic acid is converted in our body into neurotransmitters involved in the sensation of pain. Oils such as rapeseed (canola), linseed, or hempseed oil, on the other hand, contain more of the anti-inflammatory substance alpha-linolenic acid, while olive oil contains a substance with a similar effect called oleocanthal. These fats work in a similar way to ibuprofen or aspirin, but in much smaller doses.
