Fat distribution in relation to sex and socioeconomic status in children 4-19 years

Shift in body fat distribution from lower body to upper body among urban Colombian women, 1988-1989 to 2007-2008

OBJECTIVE

Body fat distribution may be a stronger predictor of metabolic risk than BMI. Yet, few studies have investigated secular changes in body fat distribution in middle-income countries or how those changes vary by socioeconomic status (SES). This study evaluated changes in body fat distribution by SES in Colombia, a middle-income country where BMI is increasing rapidly.

DESIGN

We applied factor analysis to previously published data to assess secular changes in adiposity and body fat distribution in cross-sectional samples of urban Colombian women. Anthropometry was used to assess weight, height and skinfolds (biceps, triceps, subscapular, suprailiac, thigh, calf).

SETTING

Cali, Colombia.

PARTICIPANTS

Women (18-44 years) in 1988-1989 (n 1533) and 2007-2009 (n 577) from three SES groups.

RESULTS

We identified an overall adiposity factor, which increased between 1988-1989 and 2007-2008 in all SES groups, particularly in the middle SES group. We also identified arm, leg and trunk adiposity factors. In all SES groups, leg adiposity decreased, while trunk and arm adiposity increased.

CONCLUSIONS

Factor analysis highlighted three trends that were not readily visible in BMI data and variable-by-variable analysis of skinfolds: (i) overall adiposity increased between time periods in all SES groups; (ii) the adiposity increase was driven by a shift from lower body to upper body; (iii) the adiposity increase was greatest in the middle SES group. Factor analysis provided novel insights into secular changes and socioeconomic variation in body fat distribution during a period of rapid economic development in a middle-income country.

Established and recently identified coronary heart disease risk factors in young people: the influence of physical activity and physical fitness

Epidemiological studies have identified several risk factors for coronary heart disease (CHD), many of which are present in young people. [For the purpose of this review, the phrase "young people" embraces both children and adolescents.] One such risk factor is hypertension. In adults, exercise is thought to have a positive effect on blood pressure levels; however, findings are inconclusive for young people. Despite its association with CHD, obesity is on the increase in Western society's young population; prevention and intervention during early years is needed. An active lifestyle is considered to have a beneficial effect on body fatness. Lipoprotein profiles are directly associated with CHD status. In adults, there is some evidence that physical activity and/or fitness have a favourable effect on lipoprotein levels. Although information regarding the younger population is more ambiguous, it tends to concur with these findings. High levels of lipoprotein(a), are considered an independent risk factor for CHD. Relatively little has been written on young people, although some studies have postulated a favourable relationship with physical activity. An inverse relationship between aerobic fitness and CHD has been confirmed in adults; an association is not as easily verified for young people. Physical activity is similarly deemed to have a beneficial effect on health status. A high-fat diet has been linked to CHD in adults, and evidence to date reports similar findings for young people. Smoking increases the risk of CHD and even moderate smoking during youth could have damaging long-term consequences. There is some evidence that smoking is related to physical activity and fitness levels in young people. In adults, high levels of homocyst(e)ine have been associated with CHD. As yet, little has been written on the relationship between physical activity or physical fitness and homocysteine status in young people. High levels of plasma fibrinogen have been linked to CHD. Several studies have explored the relationship between plasma fibrinogen and physical activity and/or fitness in adults, but findings are inconclusive; for young people, the ambiguity is even greater. C-reactive protein is a molecular marker for CHD but, to date, little attention has been given to this aspect, especially amongst young people. The link between high levels of plasminogen activator inhibitor-1 and CHD has been confirmed, although the essence of this relationship is not established. There is a paucity of data on the younger population and the relevance of collating such information is questionable. For the younger population, most research is limited to the established CHD risk factors and further investigations of recently identified CHD risk factors are needed.

Correlations between selected fatness indices and total body fat estimated by means of the impedance method

The aim of the present work was the evaluation of measures of total body fat and distribution of adipose tissue, including the new conicity index, and their correlation with total body fat (in kg and %) estimated by means of the impedance method. Moreover, attention was paid to the bilateral differentiation of fat distribution. The basis for the analyses and comparisons was a group of 186 females of various age. Using cluster analysis and factor analysis for fatness measures, it was shown that the measures under study form two distinctly separate groups referring to different aspects of fatness: total body fat, and adipose tissue distribution.