A new study links nicotine poisoning with weight gain, and concludes that active smokers, not only those who stop, put on more weight than non-smokers. After four years of analysis in the University of Navarra, those who put on least weight were those who had never smoked. Researchers from the Department of Preventative Medicine at the University of Navarra (UNAV) have evaluated the link between the two cardiovascular risk factors: the \u201cnicotine habit\u201d and the increase in weight when smokers stop the habit and when they continue smoking. The results, now published in the Revista Espa\u00f1ola de Cardiolog\u00eda, "are crucial for considering prevention programs," Francisco Javier Basterra-Gortari, main author of the study and researcher at UNAV, said. The data, resulting from an analysis of 7565 people over 50 months, is based on age, sex, initial body mass index and lifestyles (sedentarism, changes in physical activity, energy\/fiber intake, snacks between meals and consumption of fizzy drinks, fast food, and alcohol). Weight gain in people who stopped smoking during the study was higher the more cigarettes they smoked a day when the investigation began. Those who continued smoking also gained more weight during this period than the non-smokers. The authors confirm that nicotine addiction is not an effective way of preventing obesity. "In fact the increase is demonstrated, especially in ex-smokers and in smokers who continue," highlights Basterra-Gortari. The association between being overweight and nicotine addiction is especially harmful for cardiovascular health. Therefore, abandoning the nicotine habit has been linked to a decrease in the risk of cardiovascular illnesses and cancer. However, experts argue that weight gain after stopping smoking is, often, a reason for not quitting the nicotine addiction, especially among women. Most of the investigations that have studied this link have observed that, although there is an increase in weight after stopping smoking, there are notable variations in weight gain. "In Spain, there are very few studies on this link," concludes the researcher, who believes that "more extensive studies can confirm the results and extrapolate them to other sectors of the population."