N-3 polyunsaturated fatty acids, body fat and inflammation.

Background: Based on animal studies, n-3 polyunsaturated fatty acids (PUFAs) have been suggested to lower the risk of obesity and inflammation. We aimed to investigate if, among humans, intake of n-3 PUFAs was associated with i) total body fat, ii) body fat distribution and iii) obesity-related inflammatory markers.

Methods: The study population consisted of 1,212 healthy individuals with information on habitual food intake from food frequency questionnaires, six different measures of body fat, and levels of six circulating inflammatory markers.

Genetics of dietary habits and obesity - a twin study.

Obesity has become a major health concern due to the increased risk of co-morbidities, resulting in decreased quality of life, stigmatization, reduced working ability and early death. This causes a great challenge for the health care systems and results in increased direct costs related to treatment of obesity and co-morbidities, as well as increased indirect costs related to reduced function and withdrawal from the labour market. Both between and within societies, large variation in the prevalence of overweight and obesity exists.

Twin study of heritability of eating bread in Danish and Finnish men and women.

Bread is an elementary part of the western diet, and especially rye bread is regarded as an important source of fibre. We investigated the heritability of eating bread in terms of choice of white and rye bread and use-frequency of bread in female and male twins in Denmark and Finland. The study cohorts included 575 Danish (age range 18-67 years) and 2009 Finnish (age range 22-27 years) adult twin pairs.

A variant in the fat mass and obesity-associated gene (FTO) and variants near the melanocortin-4 receptor gene (MC4R) do not influence dietary intake.

We investigated the role of the fat mass and obesity associated gene (FTO) and variants near the melanocortin-4 receptor gene (MC4R) in modulating habitual intake of total energy and macronutrients, glycemic index, glycemic load, dietary energy density, and energy from 20 food groups in adults. In a population-based sample of 756 healthy adult twin pairs, we studied associations between FTO rs9939609, near-MC4R rs12970134, rs17700633, and rs17782313 single nucleotide polymorphisms (SNP) and habitual dietary intake. Habitual dietary intake was assessed by a 247-question FFQ.

Associations between dietary intake and body fat independent of genetic and familial environmental background.

Objective: To determine whether habitual dietary intake was associated with body fat mass and body fat distribution, independently of possible confounding by the genetic and shared environmental background.

Design And Subjects: We examined correlations between intrapair differences in specific dietary composition and intake of foods and macronutrients in relation to differences in anthropometric phenotypes in a population-based sample of monozygotic twins. Data originated from a cross-sectional study, conducted in 1997-2000, of healthy twin pairs with measured anthropometry and information from food frequency questionnaire supplemented by self-reported weight from 1994 to 2002 and self-reported waist circumference from 2002.

Modification effects of physical activity and protein intake on heritability of body size and composition.

Background: The development of obesity is still a poorly understood process that is dependent on both genetic and environmental factors.

Objective: The objective was to examine how physical activity and the proportion of energy as protein in the diet modify the genetic variation of body mass index (BMI), waist circumference, and percentage body fat.

Design: Twins from Denmark (756 complete pairs) and Finland (278 complete pairs) aged 18-67 and 21-24 y, respectively, participated.

Studies of twins indicate that genetics influence dietary intake.

Habitual dietary intake is a complex behavior that may have both biological and nonbiological bases. We estimated the contribution of genetic and environmental influences on dietary intake in a large population-based sample of healthy twins. Data originated from a cross-sectional study of 600 male and female healthy twin pairs with self-reported food consumption frequency using a validated questionnaire with 247 foods and recipes.

Common genetic components of obesity traits and serum leptin.

To estimate common and distinct genetic influences on a panel of obesity-related traits and serum leptin level in adults. In a cross-sectional study of 625 Danish, adult, healthy, monozygotic, and same-sex dizygotic twin pairs of both genders, we carried out detailed anthropometry (height, weight, waist and hip, and skin-fold thickness, body composition assessment by bioimpedance (fat mass and fat-free mass), and measurement of serum leptin level. Bivariate variance component analyses estimated the additive genetic correlations between these measurements.