Not exactly rocket science. The more weight you have in a car, the more fuel it takes to move it. The automotive industry has been obsessed with reducing the weight of cars to save fuel for decades, but perhaps, reducing the weight of the driver and passenger can go a long way to help.
The U.S. based Centers for Disease Control and Prevention (CDC) released a report earlier this month that highlighted the issues of overweight passengers and fuel usage.
According to the study around 3.8 billion litres of additional fuel has been wasted to make up for the additional increase in the weight of American drivers and passengers from 1960 to 2002.
Perhaps a better way of looking at it is to realise that for every additional pound (0.45 kg) gained by the average American, 148 million litres of additional fuel is required.
No similar study has been carried out in Australia as of yet. In a strange way, this may help explain the current American obsession and need of hybrid and eco-friendly cars.