Validity of Optical Device Lipometer and Bioelectric Impedance Analysis for Body Fat Assessment in Men and Women

The aims of this study were to validate different subcutaneous adipose tissue layers (SAT-layers) measured by lipometer for body fat percentage (BF %) assessment with dual-energy X-ray absorptiometry (DXA) and to compare the validity of lipometer and bioelectrical impedance analysis (BIA). The subjects were 21 male (18–60 years) and 19 female (23–54 years) healthy Estonian volunteers. SAT-layers were measured by lipometer using 15 standardized SAT-layers. Sum of arms, legs and trunk SAT-layers were calculated and compared with arms, legs and trunk fat percentage measured by DXA. BF% was calculated by BIA using the equations of Lukaski et al. and Chumlea et al. for both genders and the equations of Segal et al. for males and Van Loan and Mayclin for females. BF % measured by DXA was significantly higher than calculated by Lukaski et al. and Chumlea et al. in both genders. The correlation was highest between the BF% measured by DXA and using Segal et al.3 equation in males (r=0.94) and Van Loan and Mayclin equation in females (r= 0.84). High relationship was observed between BF% measured by DXA and sum of 15 SAT-layers (r=0.88 in males and r= 0.91 in females). Stepwise multiple regression analysis indicated that two selected SAT-layers explained 85.9% and 86.7% (R2 x 100) of the total variance in BF% measured by DXA in males and females, respectively: {BF% = 1.308 neck + 0.638 hip + 6.971 (males; SEE = 2.59) and BF% = 1.152 hip + 1.797 calf + 12.347 (females; SEE=3.46) }. In conclusion, lipometer and BIA give a similar mean estimation of BF% when compared with DXA. However, there is a wide range of variance for the upper and lower limits of agreement between the methods, and the methods are not interchangeable. Lipometer seems to be superior to BIA

Subcutaneous Adipose Tissue Topography (SAT-Top) Development in Children and Young Adults

The importance of body composition measurements to elucidate the dynamics of related diseases in pediatrics is gaining recognition. The methods used should not expose subjects to high doses of radiation and require substantial cooperation. The Lipometer is a new optical device that enables the non-invasive, quick and safe determination of the thickness of subcutaneous adipose tissue (SAT) layers (in mm) at any site of the human body. The topographic specification of 15 evenly distributed body sites, which makes it possible to precisely measure subcutaneous body fat distribution, is called subcutaneous adipose tissue topography (SAT-Top). SAT-Top was determined in more than 1000 children and young adults between the ages of 7 and 21. In this paper we describe the SAT-Top development of these subjects through different age groups and the differences between male and female SAT-Top development in each age group. SAT layer profiles (medians of the 15 body sites) for boys and girls in age group 1 (7–9 yrs) show a very similar pattern for both sexes, followed by slightly decreasing SAT layer thicknesses in boys and increasing values in girls in the subsequent age groups. Between age group 3 (11–13 yrs) and age group 7 (19–21 yrs) male and female SAT-Top is significantly different. The discriminating power between male and female SAT-Top was investigated by stepwise discriminant analysis, which provided no significant results for age group 1 (7–9 yrs), about 73% correct classification for age group 2 (9–11 yrs) and 3 (11–13 yrs), 83% for age group 4 (13–15 yrs), and about 91–93% for the following age groups (15–21 yrs).It is known that SAT development is the same in both sexes until puberty, when girls gain relatively more fat mass than boys to reach a higher body-fat percentage as adults. This paper presents a precise description of SAT development in boys and girls from childhood to adolescence, which provides a basis for further investigations

A Measure of Obesity: BMI versus Subcutaneous Fat Patterns in Young Athletes and Nonathletes

Although the body mass index (BMI, kg/m2) is widely used as a surrogate measure of adiposity, it is a measure of excess weight, rather than excess body fat, relative to height. The BMI classification system is derived from cut points obtained from the general population. The influence of large muscle mass on BMI in athletes and young adults may misclassify these individuals as overweight and obese. Therefore, the use of subcutaneous adipose tissue topography (SAT-Top) may be more effective than BMI in assessing obesity in physically active people and young adults. The purposes of this study were 1) to describe the relationship between the BMI and SAT-Top of young athletes and nonathletes, and 2) to determine the accuracy of the BMI as a measure of overweight. Height, weight, BMI and SAT-Top were determined in 64 males (25.0±6.7) and 42 females (24.8±7.0), who were subsequently separated into two even groups (athletes and nonathletes). The optical Lipometer device was applied to measure the thickness of subcutaneous adipose tissue (SAT).While BMI was similar, male athletes showed a 50.3% lower total SAT thickness compared to their male nonathlete controls. Even though female athletes had significantly higher BMI and weight scores, their total SAT thickness was 34.9% lower than their nonathlete controls. These results suggest subcutaneous fat patterns are a better screening tool to characterize fatness in physically active young people

Subcutaneous Fat Patterns in Type-2 Diabetic Men and Healthy Controls

The optical device LIPOMETER enables the non-invasive, quick, and save determination of the thickness of subcutaneous adipose tissue layers at any given site of the human body. The specification of 15 evenly distributed body sites allows the precise measurement of subcutaneous body fat distribution, so-called subcutaneous adipose tissue topography (SAT-Top). In the present paper we focus on SAT-Top of male type-2 diabetes patients (N=21), describing very precisely their special SAT development and their SAT-Top deviation from a healthy control group (N=111), applying factor analysis and ROC curves. Factor analysis revealed three independent subcutaneous body fat compartments, which can be summarised as »upper body«, »lower trunk« and »legs«. The upper body SAT-Top is much more pronounced in diabetic men compared to their healthy controls (p<0.001). Furthermore, high diagnostic power by ROC curve analysis was achieved by different measurement sites of the upper body and summary measures of upper body obesity (sum2, which is the sum of neck and biceps, provides: area index = 0.86, sensitivity = 81 %, specificity = 90.1 %, at an optimal cutoff value of 18.8 mm), ascribing a higher diabetes probability to subjects with a more upper body SAT-Top pattern. Calculating new ROC curves for diabetic patients with HBA1C values >8 (N=17) and their healthy controls (N=111) we received improved discrimination power for several SAT-Top body sites, especially for sum2, showing an area index of 0.91, a sensitivity of 94.1 %, and a specificity of 90.1 % at the optimal cutoff value of 18.8 mm. Concluding, the exact and complete description of the especial type 2 diabetic SAT pattern, which differs strongly from the SAT-Top of healthy controls, suggests the LIPOMETER technique combined with advanced statistical methods such as factor analysis and ROC curve analysis as a possible detecting tool for this disease

Caliper vs. Lipometer - comparing two methods of subcutaneous body fat measurement by Bland-Altman diagrams

Skinfold Calipers are widely used to obtain subcutaneous adipose tissue thickness because of its non-invasive, simple and inexpensive technique. Nevertheless, Caliper skinfold thicknesses have the disadvantage of measuring compressed adipose tissue and double layers of skin, which might reduce the precision of these results. In contrast, the computerized optical device Lipometer was developed to permit a quick, precise and non-invasive determination of non-compressed mono layers of subcutaneous adipose tissue thickness. In the present paper we investigate the hypothesis that Caliper skinfold thicknesses are significantly different from subcutaneous adipose tissue thicknesses in mm, which can be measured by Lipometer. Caliper and Lipometer results were obtained from 371 Estonian boys aged between 9.0 and 12.8 years. Measurements were performed at six different body sites: triceps, biceps, upper back, upper abdomen, hip and front thigh. Caliper measurements were systematically higher than Lipometer results in a range between 1.2 mm (hip) and 11.08 mm (front thigh). Comparing Caliper and Lipometer results very low measurement agreement was found. The two methods provided very poor interchangeability

Subcutaneous Adipose Tissue Topography in Long-Term Enterally Fed Children and Healthy Controls

In the context of enteral feeding in children the influence on growth and the question of fat resorption is of great interest. We, therefore, measured the thickness of subcutaneous body fat in a sample of long-term enterally fed toddlers and healthy controls. In 33 long-term enterally fed toddlers (10 girls, 23 boys) and 275 healthy controls (128 girls, 147 boys) subcutaneous body fat was measured by means of the optical device Lipometer. All participants were divided into three age groups (infants, toddlers, children). The height (p=0.014, -11.7 cm, -12.5%) and weight (p=0.012, -3.0 kg, -21.9%) of long-term enterally fed female toddlers were significantly lower than healthy controls, while male enterally fed toddlers had lower values in all anthropometric measures compared to healthy controls: height (p=0.003, -8.0 cm, -8.4%), weight (p<0.001, -3.5 kg, -24.8%), BMI (p=0.004, -1.3 BMI), Z-score BMI (p=0.001, -1.2 Z-score BMI), upper arm circumference (p<0.001, -1.6 cm, -10.1%) and waist circumference (p<0.001, -6.2 cm, -12.5%). Tube fed toddlers showed a similar body fat distribution when compared to healthy controls, but demonstrated significantly lower values of anthropometric measurements. The results indicate that long-term enterally fed children have ample fat stores but lack physical development

Caliper vs. Lipometer - comparing two methods of subcutaneous body fat measurement by Bland-Altman diagrams

Skinfold Calipers are widely used to obtain subcutaneous adipose tissue thickness because of its non-invasive, simple and inexpensive technique. Nevertheless, Caliper skinfold thicknesses have the disadvantage of measuring compressed adipose tissue and double layers of skin, which might reduce the precision of these results. In contrast, the computerized optical device Lipometer was developed to permit a quick, precise and non-invasive determination of non-compressed mono layers of subcutaneous adipose tissue thickness. In the present paper we investigate the hypothesis that Caliper skinfold thicknesses are significantly different from subcutaneous adipose tissue thicknesses in mm, which can be measured by Lipometer. Caliper and Lipometer results were obtained from 371 Estonian boys aged between 9.0 and 12.8 years. Measurements were performed at six different body sites: triceps, biceps, upper back, upper abdomen, hip and front thigh. Caliper measurements were systematically higher than Lipometer results in a range between 1.2 mm (hip) and 11.08 mm (front thigh). Comparing Caliper and Lipometer results very low measurement agreement was found. The two methods provided very poor interchangeability

Subcutaneous Adipose Tissue Topography in Long-Term Enterally Fed Children and Healthy Controls

In the context of enteral feeding in children the influence on growth and the question of fat resorption is of great interest. We, therefore, measured the thickness of subcutaneous body fat in a sample of long-term enterally fed toddlers and healthy controls. In 33 long-term enterally fed toddlers (10 girls, 23 boys) and 275 healthy controls (128 girls, 147 boys) subcutaneous body fat was measured by means of the optical device Lipometer. All participants were divided into three age groups (infants, toddlers, children). The height (p=0.014, -11.7 cm, -12.5%) and weight (p=0.012, -3.0 kg, -21.9%) of long-term enterally fed female toddlers were significantly lower than healthy controls, while male enterally fed toddlers had lower values in all anthropometric measures compared to healthy controls: height (p=0.003, -8.0 cm, -8.4%), weight (p<0.001, -3.5 kg, -24.8%), BMI (p=0.004, -1.3 BMI), Z-score BMI (p=0.001, -1.2 Z-score BMI), upper arm circumference (p<0.001, -1.6 cm, -10.1%) and waist circumference (p<0.001, -6.2 cm, -12.5%). Tube fed toddlers showed a similar body fat distribution when compared to healthy controls, but demonstrated significantly lower values of anthropometric measurements. The results indicate that long-term enterally fed children have ample fat stores but lack physical development

Estimating DXA Total Body Fat Percentage by Lipometer Subcutaneous Adipose Tissue Thicknesses

DXA is an accepted reference method to estimate body composition. However several difficulties in the applicability exist. The equipment is rather expensive, not portable, impractical for measurement of big study populations and it provides a minimal amount of ionizing radiation exposure. The optical device Lipometer (EU Pat.No. 0516251) provides non-invasive, quick, precise and safe measurements of subcutaneous adipose tissue (SAT) layer thicknesses at any site of the human body. Compared to DXA there are some advantages in the Lipometer approach, because this device is portable, quick, not expensive and no radiation is involved. To use these advantages in the field of total body fat% (TBF%) assessment, an acceptable estimation of DXA TBF% by Lipometer SAT thicknesses is necessary, which was the aim of this study. Height, weight, waist and hip circumferences, DXA TBF% and Lipometer SAT thicknesses at fifteen defined body sites were measured in 28 healthy men (age: 33.9 ± 16.6 years) and 52 healthy women (age: 40.1 ± 10.7 years). To estimate Lipometer TBF% stepwise multiple regression analysis was applied, using DXA TBF% as dependent variable. Using the fifteen Lipometer SAT thicknesses together with age, height, weight and BMI as independent variables provided the best estimations of Lipometer TBF% for both genders with strong correlations to DXA TBF% (R=0.985 for males and R=0.953 for females). The limits of agreement were –2.48% to +2.48% for males and –4.28% to +4.28% for females. For both genders we received a bias of 0.00%. The results of this paper extend the abilities of the Lipometer by a precise estimation of TBF% using DXA as »golden standard«