Funny you should mention coconut oil Gilly
"Cattle ranchers discovered the difference between saturated and unsaturated fats in the 1940s, when they fed their livestock inexpensive coconut oil (a saturated fat) in order to fatten them for market. But the cattle didn’t gain weight. Instead, coconut oil made them lean, active, and hungry. Next, ranchers tested a thyroid-suppressing drug. As expected, the livestock gained weight on less food, but because the drug was strongly carcinogenic, it was discontinued. By the late 1940s, ranchers discovered that soybeans and corn caused the same anti-thyroid effect as the thyroid-suppressing drug, allowing animals to gain more weight on less food. Since then, corn and soy have been the staples of feedlot cattle.
A later experiment fed animals pure unsaturated vegetable oil, pure saturated coconut oil, and various mixtures of the two. The animals’ obesity increased in proportion to the ratio of unsaturated fat in their diet, independent of the total amount of fat or calories they consumed. Animals that ate even small amounts of unsaturated oil were fat, and those that ate large amounts of coconut oil were thin."
thescreamonline.com/essays/essays5-1/vegoil.html
My step daughter has gone as far as completely removing processed, unsaturated fats from her diet. It does involve a lot more work than say sticking a ready meal in the oven but not as much as you'd think. It doesn't seem to break her bank particularly. I will say that whilst it's not a scientific observation, she does look healthier for it.