Cannabinoid type 1 receptor gene polymorphism and macronutrient intake

Background: Cannabinoid type 1 receptor (CB1-R) is a key mediator in the control of food intake and is linked to obesity. Aim: To evaluate the relationship between CB1-R gene polymorphism and dietary macronutrient intake in elderly subjects. Methods: This study included 118 subjects (60 males, 58 females) from a population survey carried out in southern Italy in 1992-1993 who were older than 65 years and previously characterized for CB1-R polymorphism (75 with GG wild-type genotype, 41 with heterozygous polymorphic allele AG, and 2 with genotype AA). All subjects completed a validated semi-quantitative food frequency questionnaire. Statistical methods included multiple logistic regression to model macronutrient intake to genotype, controlling for potential confounders. Results: When controlled for age, gender, and body mass index, the intake of dietary cholesterol and saturated fats corrected for calories was inversely associated with the CB1-R 1359 G/A polymorphism, while the intake of starchy carbohydrates was directly associated with this polymorphism. Conclusion: In our unselected elderly population, the 1359 G/A polymorphism is linked with a specific macronutrient intake. This could be explained by the role of the cannabinoid system as a determinant of food intake and eating behavior.