title: Associations of the lactase persistence allele and lactose intake with body composition among multiethnic children.
abstract: Childhood obesity is a worldwide health concern with a multifaceted and sometimes confounding etiology. Dairy products have been implicated as both pro- and anti-obesogenic, perhaps due to the confounding relationship between dairy, lactose consumption, and potential genetic predisposition. We aimed to understand how lactase persistence influenced obesity-related traits by observing the relationships among lactose consumption, a single nucleotide polymorphism (SNP) near the lactase (LCT) gene and body composition parameters in a sample of multiethnic children (n = 296, 7-12 years old). We hypothesized that individuals with the lactase persistence (LP) allele of the LCT SNP (rs4988235) would exhibit a greater degree of adiposity and that this relationship would be mediated by lactose consumption. Body composition variables were measured using dual X-ray absorptiometry and a registered dietitian assessed dietary intake of lactose. Statistical models were adjusted for sex, age, pubertal stage, ethnic group, genetic admixture, socio-economic status, and total energy intake. Our findings indicate a positive, significant association between the LP allele and body mass index (p = 0.034), fat mass index (FMI) (p = 0.043), and waist circumference (p = 0.008), with associations being stronger in males than in females. Our results also reveal that lactose consumption is positively and nearly significantly associated with FMI.
authors.affiliation: Department of Nutrition Sciences, University of Alabama at Birmingham, Webb 449A-1720 Second Avenue South, Birmingham, AL, 35294-3360, USA.
authors.forename: Adil J
authors.initials: AJ
authors.lastname: Malek
authors.forename: Yann C
authors.initials: YC
authors.lastname: Klimentidis
authors.forename: Kenneth P
authors.initials: KP
authors.lastname: Kell
authors.forename: José R
authors.initials: JR
authors.lastname: Fernández