Lipid, protein and carbohydrate intake in relation to body mass index: an Italian study

The Specific Impact of Nutrition and Physical Activity on Adolescents' Body Composition and Energy Balance

Purpose: The aim of the present study was to identify the contribution of nutrition, physical activity (PA), and total energy intake and expenditure on body weight and composition in adolescents. Methods: Body composition, PA, and dietary intakes from 904 Greek adolescents (446 boys and 458 girls; Age: 14.6 ± 1.5 yrs), were evaluated. All participants were assigned into three groups according to their age-sex adjusted Fat Mass Index: (A) Normal weight (N; N = 503), (B) Overweight (OW; N = 253), and (C) Obese (O; N = 148). Results: Significant differences were found for body weight and composition, basal metabolic rate (BMR) expressed per kg of body mass (normal weight children exhibited the highest values), physical-total energy expenditure, and energy balances between the groups (η²: 0.138 to 0.657; p < .05). In contrast, no differences were found for macronutrients' and total energy intakes, food consumption and quality (η²: 0.002 to 0.099; p > .05) between the three examined groups. Strong, negative correlations were observed between body weight, body fat percentage, PA, and total energy expenditure (r: -0.311 to -0.810; p < .001). Lower, negative correlations were found between body weight, body fat percentage, and macronutrients' daily intakes (r:-0.235 to -0.432; p < .05). BMR and total energy expenditure had strong, negative relative strengths for the determination of body weight and fat percentage. Conclusions: In conclusion, it seems that BMR, PA, and total daily energy expenditure expressed per body weight and not the nutritional and total energy intakes, were the primary determinant parameters of body composition and weight in adolescents.

Association between body mass index and macronutrients differs along the body mass index range of German adults: results from the German National Nutrition Survey II

The aim of the present study was to determine whether the association between body mass index (BMI) and the intake of macronutrients varies along the BMI distribution of German adults. Based on a sample of 9214 men and women aged 18-80 years from the representative cross-sectional German National Nutrition Survey (NVS) II, quantile regression was used to investigate the association between BMI and the intake of macronutrients independent of energy intake and other predictors. In both sexes, BMI was positively associated with the intake of total protein and animal protein over its entire range and negatively associated with vegetable protein. A negative association between BMI and the intake of polysaccharides was found along the entire range of BMI in men. There was a weak negative association between BMI and the intake of total fat and saturated fatty acids observed in normal-weight-range women only. In conclusion, the association between BMI and the intake of macronutrients varies along the BMI range. Animal protein intake is positively associated with BMI independent of energy intake in both sexes whereas only in men an inverse association of polysaccharide intake with BMI was shown.

Trends in energy and macronutrient intakes by weight status over four decades

OBJECTIVE

To examine whether the recent increasing prevalence of obesity was accompanied by variations in energy and macronutrient intakes by weight status.

DESIGN

Time series of cross-sectional surveys.

SETTING

National Health and Nutrition Examination Surveys (NHANES) in the USA.

SUBJECTS

Adult participants of NHANES I (1971-1974), II (1976-1980), III (1988-1994) and continuous (1999-2004).

RESULTS

Daily energy intake increased over time for men (9832 to 11 652 kJ, P < 0·01) and women (6418 to 8142 kJ, P < 0·01) in all BMI classes. Percentage of energy intake from carbohydrate increased over time (men: 42·7% to 48·0%, P < 0·01; women: 45·4% to 50·6%, P < 0·01), whereas percentage of energy intake from fat (men: 36·7% to 33·1%, P < 0·01; women: 36·1% to 33·8%, P < 0·01) and protein (men: 16·4% to 15·1%, P < 0·01; women: 16·9% to 14·7%, P < 0·01) decreased. With surveys combined, daily energy intake varied among BMI classes for women (underweight/normal weight: 7460 kJ; overweight: 6799 kJ; obese I: 7033 kJ; obese II/III: 7401 kJ; P < 0·01) but not men. Percentage of energy intake from carbohydrate decreased with increasing BMI class (men: 46·6% to 45·5%, P < 0·01; women: 49·0% to 48·6%, P < 0·01) whereas percentage of energy intake from fat (men: 34·3% to 36·5%, P < 0·01; women: 34·4% to 35·4%, P < 0·01) and protein (men: 15·3% to 16·5%, P < 0·01; women: 15·2% to 16·0%, P < 0·01) increased. Interactions of survey period and BMI class were not statistically significant.

CONCLUSIONS

Time trends in energy and macronutrient intakes were similar across BMI classes. Research examining how individuals respond differently to varying dietary compositions may provide greater insight about contributors to the rise in obesity.

Correlates of childhood obesity in Athens, Greece

OBJECTIVE

Childhood obesity is a growing public health problem. We have examined the association between sociodemographic profile and eating and physical activity patterns with overweight among primary-school students in Athens, Greece.

DESIGN

Cross-sectional study.

SETTING

Eleven primary schools in the greater Athens area, Greece.

SUBJECTS

A total of 633 children aged 10-12 years (50 % boys, 50 % girls) were interviewed in person during spring 2003. Multivariate logistic regression was used to investigate the association between eating and physical activity patterns and overweight (> or =85th sex- and age-specific BMI centile). Results are presented as odds ratios and 95 % confidence intervals.

RESULTS

Overweight was more common among girls than among boys (OR=1.73; 95% CI 1.11, 2.69) and substantially less common among children born outside Greece (OR=0.46; CI 0.22, 0.95). Reported physical activity (per 1.5 h per day) was unrelated to overweight (OR=0.97; CI 0.85, 1.12) but patent physical inactivity, operationalised as time spent watching television or working/playing with the computer (per 1.5 h per day) was a highly significant predictor of overweight (OR=1.20; CI 1.05, 1.36). Composition of diet was unrelated to overweight but the daily number of eating occasions, controlling for total energy intake, was significantly inversely associated with overweight (OR=0.61; CI 0.48, 0.76).

CONCLUSIONS

The principal factor underlying overweight among children in Athens appears to be the extended inactivity imposed by modern childhood lifestyles. An intriguing finding is that spreading a given energy intake over several eating occasions was inversely associated with the likelihood of childhood obesity.