Unsaturated Fat and Wrinkles

While saturated fats help prevent wrinkles, unsaturated fats actually contribute to wrinkles. That's because unsaturated fats are usually rancid and contain free radicals that do a lot of damage inside the body - including promoting wrinkles. Studies performed by several plastic surgeons during the 1980's found that women who consumed lots of vegetable oil had far more wrinkles and looked much older than women who consumed saturated fats.

— Sally Fallon & Mary Enig
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