BACKGROUND:
High oxidative stress, which is caused by smoking, can alter omega-3 fatty acid concentrations. Since omega-3 fatty acids play a role in dopaminergic neurotransmission related to dependence, it is important to understand their effects on nicotine dependence.
METHODS:
This research comprised 2 studies. The first one consisted of a cross-sectional evaluation, in which the levels of the most important omega-3 fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), were compared between smokers and non-smokers in a sample of 171 individuals; of them, 120 were smokers and 51 were non-smokers. The other study was a clinical, double-blind, randomized, placebo controlled, in which 63 smokers received daily treatment with capsules of fish oil (a source of omega-3/3 g/day) or mineral oil (used as placebo, also 3 g/day), taken 3 times a day for 90 days. Each fish oil capsules contained approximately 210.99 mg EPA and 129.84 mg of DHA. The outcome was evaluated by means of psychometric and biological measures as well as self-reports of tobacco use. The evaluations were carried out at the beginning of treatment and once a month thereafter (total of 4 times).
OUTCOMES:
The omega-3 fatty acid lipid profile showed that smokers present lower concentrations of DHA. After treatment, the omega-3 group showed a significant reduction in their levels of dependence.
INTERPRETATION:
Smokers showed lower peripheral levels of omega-3, and treatment with the most important omega-3 fatty acids brought about a reduction in nicotine dependence.