From a scientific angle, the main difference between American Spirit Orange and Blue boils down to nicotine delivery. While both contain tobacco, the way the leaves are blended or processed can affect how much nicotine is released when smoked. Scientists emphasize that regardless of 'additives,' burning tobacco creates thousands of chemicals, many of which are harmful. The perceived 'lightness' or 'strength' is often due to nicotine content and also how much air is mixed with the smoke through filter ventilation. Even a 'lighter' cigarette still exposes the smoker to dangerous substances.