Even if you consider yourself a light or "casual" smoker, it does not necessarily mean that you have completely escaped nicotine addiction, warns new research.

Many light smokers – those who smoke one to four cigarettes per day or fewer – meet the criteria for nicotine addiction and should, therefore, be considered for treatment, said the study published in the American Journal of Preventive Medicine.

"In the past, some considered that only patients who smoke around 10 cigarettes per day or more were addicted, and I still hear that sometimes," said Jonathan Foulds, Professor at Pennsylvania State University in the US.