Palm oil’s world domination is the result of five factors: first, it has replaced less healthy fats in foods in the west. Second, producers have pushed to keep its price low. Third, it has replaced more expensive oils in home and personal care products. Fourth, again because it is cheap, it has been widely adopted as cooking oil in Asian countries. Finally, as those Asian countries have grown richer, they have begun to consume more fat, much of it in the form of palm oil.
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