Fat is a solid oil. It is a natural part of many foods. Animals eat food and convert much of it directly into energy. But if they can, they will eat more than they need immediately. The body tells them to do this so it can tuck some of the food away in case there is no meal coming soon. This is something we have inherited from the days when we were wild animals.

The most efficient way of storing the food we don't immediately need is to convert it into fat. Fat is a concentrated form of energy.

Fat is essential. But as we now have as much food as we want, we have to control the amount of food we eat so that we don't store more fat than we really need. The body will keep storing food if we keep eating it. It does not have any natural controls to stop storing it. This is why many people get fat (obese). One way to cut back on our own fat is to eat less. Another way is to eat less fatty food. Another is to use up more food by exercising.

But there is another reason to eat less animal fat. That is because it is converted into a kind of fat that can block up our blood vessels and cause heart attacks.

As with everything, a little fat is good for you, a lot is bad.