About 30 years ago a young cardiology doctor called Robert C. Atkins came up with a revolutionary diet plan he named after himself.
The basis of this plan was the idea that we are not getting fat from the fat in our food. How else, he said, would we explain the obesity in the United Stated, where there are so many low fat foods?

The culprits, he uncovered, are the carbohydrates. Those building blocks turn into glucose and if we do not use all of that energy on physical activity, it turns into fat and accumulates in our bodies.

Therefore his diet is based on a few or no carbohydrates at all. You can eat as much proteins (meat and animal products) as you like and you can eat as much fat as you like, as long as you avoid carbohydrates you will lose weight.