Dr Robert Atkins was an American heart doctor (cardiologist) who first described the diet. Normally our bodies use glycogen (stored carbohydrate) for energy, but the body uses fat stores for energy when the glycogen runs out. Dr Atkins read about a diet low in carbohydrates which could help the body switch to burning fat instead of glucose as fuel.
This is a companion discussion topic for the original article at https://patient.info/healthy-living/weight-loss-weight-reduction/atkins-diet