If coconut oil can boost metabolism and reduce appetite, then it should help you lose fat over the long term.
In fact, there are several studies that port this.

In one study, 40 women were given either 30 grams (2 tablespoons) of either coconut oil or soybean oil for 28 days.
They were instructed to eat fewer calories and walk every day. These were the results:
Both groups lost weight (about 2 pounds).
Only the coconut oil group had decreased waist circumference (belly fat) while the soybean oil actually had a mild increase in belly fat.
The coconut oil group had increased HDL (good) cholesterol levels, while the soybean oil had reduced HDL and increased LDL.