Smokers who quit have metabolite levels that resemble those of nonsmokers

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The researchers regularly collected blood, urine and saliva samples from male volunteers, who were trying to quit smoking, up to three months after smoking cessation. To minimize nutritional effects on metabolism, the researchers strictly controlled the volunteers' diets during four in-patient stays. To ensure compliance, they measured levels of carbon monoxide and cotinine, a nicotine metabolite which can be detected in urine and saliva over several days after someone has smoked. In the study, the researchers analyzed the experimental samples with an untargeted metabolic fingerprinting approach. Overall, the researchers identified 52 metabolites that were significantly altered after the subjects stopped smoking, including several that showed reversible changes toward that of a nonsmoker's metabolic profile. The team concluded that these compounds could one day be used as biomarkers for smoking-induced biological changes. Moreover, the researchers state that the published method would be also useful for evaluating the benefits, if any, for smokers when switching to new products like electronic cigarettes. The authors acknowledge funding from Imperial Brands PLC and Analytcish- biologisches Forschungslabor (ABF) GmbH. In the paper, the authors state, "There has not been any influence on the work or publication by the sponsor Imperial Brands plc." "Metabolic Fingerprinting in Various Body Fluids of a Diet-Controlled Clinical Smoking Cessation Study Using a Validated GC-TOF-MS Metabolomics Platform"

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