AMERICAN JOURNAL OF HUMAN BIOLOGY 1 :631448 (1989)

Fatness and Fat Distribution in Mexican-American Children and Youths From the Hispanic Health and Nutrition Examination Survey

HALEY KAPLOWITZl, REYNALDO MARTORELV, AND FERNANDO S. MENDOZA2 'Food Research Institute and 'Department of Pediatrics, Stanford University Medical School, Stanford, California 94305

ABSTRACT Mexican-American children are shorter but relatively heavier than non-Hispanic white children. The excess relative weight is probably due to increased fat rather than lean body mass and, more specifically, to increased fat deposition on the upper trunk sites. The objective of this paper is to describe the level of fatness and fat distribution in a large, representative sample of Mexican- American children and adolescents from the recently completed Hispanic Health and Nutrition Examination Survey (HHANES). As expected, Mexican-American children are generally fatter than white children measured in previous national surveys (National Health and Nutrition Examination Survey [NHANESI 11, Health Examination Survey [HES]). Differences are particularly evident for trunk skinfold thicknesses and generally increase with age. Indices of fat distribution clearly show a centralized, upper body adiposity pattern among Mexican-Ameri- cans, a cause for concern since greater fat deposition on the trunk has been associated with increased risk of certain chronic diseases.

A number of recent studies have indicated that Mexican-American children tend to be shorter but relatively heavier than U.S. non- Hispanic white children (Malina et al., 1983, 1987; Mueller et al., 1984; Martorell et al., 1987; Yanochik-Owen and White, 1977; Kautz and Harrison, 1981; Dewey et al., 1983). Evidence suggests that this excess relative weight is due to an increase in body fat rather than to an increase in lean body mass (Malina et al., 1986,1987; Guinn et al., 1986). Other researchers have shown that this increase in fat is disproportionately dis- tributed on the body, causing Mexican- Americans to be more centralized in their distribution of adiposity (Mueller et al., 1984; Haffner et al., 1986b,c; Mueller, 19881, possibly increasing their risk of certain chronic diseases in later life, such as nonin- sulin-dependent diabetes mellitus and car- diovascular disease (Joos et al., 1984; Haffner et al., 1986a,c; Reichley et al., 1987).

Until now, research has generally been limited to relatively small samples of Mexi- can-Americans from highly specific areas of the United States and from lower socioeco- nomic strata. The present study seeks to describe the pattern of body fat distribution

in Mexican-American children from birth through adolescence using data from the recently completed Hispanic Health and Nu- trition Examination Survey (HHANES), which provides the largest, most current body of data on Mexican-Americans. A sec- ond objective of this study is to compare adiposity patterns in Mexican-Americans and U.S. non-Hispanic white children.

MATERIALS AND METHODS Survey design and data collection

The HHANES data used here were col- lected by the National Center for Health Statistics (NCHS) between 1982 and 1984. This survey was conducted to characterize the health and nutritional status of three Hispanic groups in the United States: Puerto Ricans from the New York City area, includ- ing parts of New Jersey and Connecticut; Cuban-Americans from Dade County, Flor- ida; and Mexican-Americans from Arizona,

Received December 13,1988; accepted May 15,1989. Address reprint requests to Haley Kaplowitz, Food Research

Institute, Stanford University, Stanford, CA 94305.

@ 1989 Alan R. Liss, Inc.

63 2 H. KAPLOWITZ ET AL.

Colorado, New Mexico, Texas, and Califor- nia (NCHS, 1985).

The HHANES study design was similar to that of the previous National Health and Nutrition Examination Surveys in that all of these surveys used a complex, multistage, stratified, cluster sampling design of specif- ically designated populations. The major dif- ference between HHANES and the previous surveys is that HHANES was a survey of three special subgroups of the population in selected areas of the United States rather than a national probability sample (NCHS, 1985).

This paper uses only a subset of the survey data; specifically, anthropometric data col- lected on Mexican-American children and youths from birth to 17 years of age. The first-stage sampling universe for the Mexi- can-American portion of HHANES included about 84% of the 1980 Mexican-origin popu- lation in the United States and about 97% of the 1980 Mexican-origin population in the five southwestern states mentioned above. Height was measured to the nearest 0.1 cm in children 2 years of age and older, and recumbent length was measured to the near- est 0.1 cm in children under age 2 years. Weight was measured to the nearest 0.01 kg, including the weight of light clothing. Skin- fold thicknesses, including the triceps, sub- scapular, suprailiac, and medial calf sites, were measured on the right side of the body to the nearest 0.5 mm. Additional method- ologic details are provided elsewhere (NCHS, 1985).

Descriptive statistics Age- and gender-specific descriptive sta-

tistics for all anthropometric measurements have been reported elsewhere (Najar and Kuczmarski, 1989; Martorell et al., in press).

An index of fat distribution was derived by taking the ratio of the subscapular to the triceps skinfold thicknesses. This index of centralized or truncal fat patterning has been used repeatedly in previous research (Blair et al., 1984; Bogin and MacVean, 1981; Frisancho and Flegel, 1982; Lapidus et al., 1984; Bailey et al., 1985; Kaplowitz et al., 1987; Roche and Baumgartner, 1988; Haffner et al., 1986a,b). Descriptive statis- tics for the subscapularltriceps index are reported by gender for all ages (in completed years). Since this survey used a complex sample design, sample weights were neces- sary to estimate central tendency statistics.

Means and percentiles were therefore calcu- lated taking these sample weights into ac- count. Differences between weighted and unweighted values were generally trivial. Fifth, loth, 25th, 50th (median), 75th, 90th, and 95th percentiles are reported for ages at which there were sufficient numbers of sub- jects. As recommended by the National Cen- ter for Health Statistics (Najjar and Kuczmarski, 1989), a minimum of 100 obser- vations is necessary to obtain reliable esti- mates of the 5th and 95th percentiles; therefore, these figures have not been re- ported in some instances.

In spite of the frequency of its use, the subscapular to triceps ratio does not gener- ally discriminate between centralized and peripheral adults with a high degree of sen- sitivity (Kaplowitz et al., 1987). Addition of a lower limb measurement, such as the medial calf, substantially improves the assessment of fat distribution (Kaplowitz et al., 1987; Mueller and Stallones, 1981). Therefore, two additional indices of fat distribution were calculated: the ratio of the subscapular and suprailiac skinfold thicknesses to the triceps and medial calf measures, hereafter referred to as the trunklextremity index; and the ratio of the subscapular and triceps measures to the medial calf skinfold thickness, hereafter referred to as the upperllower body index. Descriptive statistics were calculated for these two indices a t all ages as above. The suprailiac measurement was omitted from the upperAower body ratio because of uncer- tainty as to whether it should be considered an upper or a lower body measurement. A ratio of 1.0 indicates a uniform thickness of the subcutaneous fat layer across the trunk and extremity or upper and lower body sites.

Comparisons to NHANES I1 Median values for body mass index (BMI),

triceps and subscapular skinfold thick- nesses, and the subscapularltriceps ratio were then compared with weighted percen- tiles calculated for non-Hispanic white chil- dren and youths from the second National Health and Nutrition Examination Survey (NHANES 11). Data from this survey were collected between 1976 and 1980 and provide the largest, most recent body of data for non-Hispanic whites (i.e., those children ob- served to be of “white” ethnic background, but not of Hispanic ancestry) (McDowell et al., 1981).

Comparisons with HES Cycle 111 The NHANES I1 anthropometric battery

did not include the suprailiac and medial calf skinfold thicknesses. The only US. national sample that included all four of the same skinfold measurements, and therefore al- lowed for the calculation of these additional fat distribution indices, was Cycle I11 of the Health Examination Survey (HES). This survey was also conducted by NCHS, but, unfortunately in this case, included only ad- olescents between the ages of 12 and 17 years. Although these data are about 20 years old, they are valuable because they allow patterns of fat distribution during ad- olescence to be examined with a larger and more varied number of measurements. Therefore, comparisons of weighted medians for the suprailiac and medial calf skinfold measures and for the trunklextremity and uppertlower body fat distribution indices were made with HES Cycle I11 percentiles for the adolescent age group only.

Secular trend HHANES was collected between 1982 and

1984, NHANES I1 between 1976 and 1980, and HES Cycle I11 from 1966 to 1970. Thus the possibility of a secular trend in fatness and fat distribution is a potential source of bias in between-survey comparisons. There- fore, weighted medians for BMI, triceps and subscapular skinfold thicknesses, as well as the subscapular/triceps ratio from the NHANES I1 and HES were compared within age groups and gender (Table 1) to deter- mine whether change over time in these

633 FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS

measures needed to be considered when making comparisons between the Mexican- American and reference curves. Differences in median values for skinfold thicknesses and indices were generally small, although triceps differences in adolescent girls tended to increase with age while subscapularl triceps differences in girls tended to decrease with age. The results are generally consis- tent with the work of Flegal et al. (1988a,b), who found relatively small but significant positive secular trends in BMI that in- creased with age. It is unclear, however, how much of the trend is real and how much is due to changes in measuring techniques across surveys. Even if all of the trend were real, however, its magnitude is small. Thus the HES data can be regarded as appropriate for the purposes of this study.

Measurement reliability Every participant whose identification

number ended in a 3 or a 6 was measured on the left side of the body in addition to the right side. This involved approximately 20% (N = 716) of the sample. Martorell and col- leagues (198813) found average values for the differences between the right and left sides to be small for both the triceps and subscap- ular skinfold thicknesses (0.48 and -0.11 mm, respectively), less than one tenth of a standard deviation. Since differences associ- ated with body side were systematic and since similar measurement techniques were used, left and right side measures were con- sidered to be “repeated measures in order to estimate intraexaminer precision.

TABLE 1. Median body mass index (BMI), triceps and subscapular skinfold thicknesses, and subscapular/triceps ratio for non-Hispanic white adolescents from the HES Cycle III and NHANES II‘

BMI Triceps Subscapular Subscap./Triceps Age HES NHANES HES NHANES HES NHANES HES NHANES (years) I11 I1 111 I1 111 I1 111 I1

Males 12 17.9 17.9 9.5 11.5 5.5 6.5 0.64 0.64 13 18.7 18.9 9.0 9.0 6.0 7.0 0.71 0.74 14 19.7 19.5 8.0 9.0 6.0 7.0 0.83 0.82 15 20.5 20.1 7.5 7.5 6.5 7.0 0.94 0.92 16 20.7 21.5 7.5 8.0 7.0 8.0 1 .00 1.00 17 21.5 21.3 7.5 7.0 7.5 8.0 1.07 1.18

12 18.5 18.3 12.0 13.5 7.5 8.5 0.70 0.64 13 19.5 19.2 12.5 15.0 8.0 9.0 0.72 0.68 14 20.1 20.4 14.0 17.0 9.5 10.0 0.71 0.68 15 20.6 20.0 15.0 16.5 10.0 10.5 0.72 0.73 16 21.0 21.0 16.0 18.5 10.5 11.5 0.73 0.69 17 21.0 21.7 16.0 20.0 11.0 12.5 0.73 0.71

Females

‘BMI in kg/rn2, triceps and subscapular skinfolds in mm.

634 H. KAPLOWITZ ET AL

Intraexaminer measurement error vari- ances were calculated for each of the four skinfold measurements, as well as for the three fat distribution indices, using the fol- lowing equation (Habicht et al., 1979):

The measurement error variance, S;, is equal to the squared difference between the measures on the two sides, d2 (e.g., the square of the right minus the left triceps), summed across i subjects, and divided by two times the number of subjects for whom there are “repeated” measures. Intersubject vari- ance, S2, for each measure was calculated using the right side data available on all 3,595 HHANES subjects.

“he reliability coefficient (R), which in this case is an estimate of intraexaminer preci- sion, was calculated as (Habicht et al., 1979)

R = 1 - (Sg/S2),

where Sg is the measurement error variance and S2 is the intersubject variance. All anal-

yses were done within the age groups com- monly used by NCHS (<2, 2-5, 6-11, and 12-17 years) and independently for males and females.

Table 2 presents measurement error vari- ances, intersubject variances, and reliability coefficients by age and gender. Reliability coefficients are all above 0.90 for the four skinfold measurements. Fat distribution in- dices are slightly lower, ranging from 0.75 to 0.92 in boys and from 0.78 to 0.96 in girls. Measurement precision for these ratios tends to increase with age, particularly in boys.

RESULTS Descriptive statistics for the three indices

of fat distribution, including weighted means and percentiles, are reported by gen- der in Tables 3 through 5. Figure 1 depicts median BMI values by age for males and females, respectively, against NHANES I1 percentiles. Mexican-American boys and girls are relatively heavier than non-His- panic white children. Both genders grow above the 50th percentile of the reference curves throughout the age range, although

TABLE 2. Measurement error and reliability of fatness and fat distribution measures’

Males Females Age (vears) Variable MEV S2 R MEV S2 R

2-5

6-11

12-17

<2 Triceps Subscapular Suprailiac Medial calf Subscap./triceps Trunk/extremity Upper/lower Triceps Subscapular Suprailiac Medial calf Subscap./triceps Trunk/extremity Upper/lower Triceps Subscapular Suprailiac Medial calf Subscap./triceps Trunk/extremity Upper /lower Triceps Subscapular Suprailiac Medial calf Subscap./triceps Trunk/extremity Uooer/lower

0.6757 0.3007 0.3176 0.8209 0.0079 0.0020 0.0166 0.5382 0.2039 0.7724 0.4737 0.0043 0.0037 0.0498 0.8365 0.3590 1.1635 0.6974 0.0065 0.0062 0.0441 0.9652 0.4059 2.0103 1.4691 0.0088 0.0117 0.0848

8.867 3.790

10.224 13.517 0.033 0.014 0.082 9.645 5.955

14.771 10.030 0.031 0.035 0.216

40.824 42.319

122.495 45.277 0.043 0.074 0.327

49.639 56.449

137.912 53.516 0.110 0.166 0.655

0.9238 0.9207 0.9689 0.9393 0.7598 0.8533 0.7984 0.9442 0.9658 0.9477 0.9528 0.8631 0.8942 0.7696 0.9795 0.9915 0.9905 0.9846 0.8507 0.9160 0.8653 0.9806 0.9928 0.9854 0.9725 0.9199 0.9296 0.8705

0.6007 0.2813 0.8368 0.5000 0.0033 0.0025 0.0180 0.7453 0.3434 1.0348 0.7025 0.0044 0.0040 0.0266 0.7779 0.8450 1.3564 1.0599 0.0046 0.0042 0.0369 1.1102 1.1261 2.0286 1.8136 0.0061 0.0051 0.0661

6.799 6.156

10.956 10.879 0.042 0.024 0.082

10.844 8.798

19.233 11.238 0.027 0.033 0.145

39.782 51.310 88.345 42.069 0.062 0.079 0.300

53.470 78.911 87.025 63.151 0.067 0.075 0.406

0.9117 0.9543 0.9236 0.9540 0.9204 0.8954 0.7789 0.9313 0.9610 0.9462 0.9375 0.8379 0.8803 0.8169 0.9804 0.9835 0.9846 0.9748 0.9256 0.9465 0.8769 0.9792 0.9857 0.9767 0.9713 0.9082 0.9314 0.8373

‘Age is in completed years; MEV, measurement error variance; S2, intersubject variance; R, reliability coefficient.

FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS 635

TABLE 3. Sample sizes, minimum a.nd maximum values, means, standard deviations, and percentiles for the subscapular/triceps ratio (mm) for Mexican-Americans from the Hispanic Health and Nutrition Examination

Survey (HHANES)

Percentiles Minimum Maximum Age N value value Mean SD 5th 10th 25th 50th 75th 90th 95th

Males 0 1 2 3 4 5 6 7 8 9

57 0.42 104 0.32 111 0.32 130 0.34 118 0.32 116 0.15 110 0.34 110 0.33 102 0.29 106 0.38

1.33 0.67 1.80 0.65 1.71 0.64 1.25 0.60 1.88 0.59 1.30 0.60 1.26 0.63 1.30 0.64 1.32 0.65 1.30 0.65

0.17 -l 0.50 0.19 0.42 0.45 0.21 0.38 0.43 0.15 0.39 0.41 0.18 0.38 0.43 0.17 0.40 0.42 0.18 0.42 0.45 0.20 0.40 0.42 0.19 0.39 0.42 0.18 0.42 0.43

10 88 0.36 1.35 0.72 0.22 - ~~

11 115 0.25 1.64 0.72 0.25 0.40 12 114 0.12 1.77 0.78 0.26 0.45 13 97 0.31 1.43 0.79 0.21 - 14 97 0.43 1.71 0.91 0.28 - 15 69 16 76 17 71

0 63 1 119 2 118 3 96 4 96 5 109 6 118 7 96 8 107 9 125

Females

0.44 0.42 0.54

0.47 0.36 0.30 0.35 0.28 0.31 0.36 0.29 0.31 0.25

1.60 2.23 3.27

1.89 1.43 1.15 1.00 1.00 1.20 1.39 3.00 1.26 1.49

0.96 1.07 1.20

0.77 0.69 0.65 0.60 0.59 0.61 0.63 0.64 0.63 0.74

0.25 - 0.32 - 0.48 -

0.23 - 0.19 0.44 0.18 0.41 0.14 - 0.16 - 0.17 0.38 0.19 0.40

0.20 0.39 0.25 0.38

0.30 -

10 94 0.33 1.63 0.74 0.28 - ~.

11 115 0.29 1.47 0.73 0.24 0.45 12 103 0.29 1.48 0.78 0.23 0.47 13 89 0.42 1.75 0.79 0.28 - 14 75 0.40 1.38 0.79 0.22 - 15 85 0.47 1.42 0.86 0.24 - 16 99 0.28 1.56 0.83 0.27 - 17 75 0.46 1.77 0.92 0.29 -

'Dashes indicate insufficient sample size (see Materials and Methods).

0.44 0.45 0.53 0.55 0.59 0.67 0.71 0.71

0.54 0.48 0.45 0.44 0.42 0.43 0.44 0.43 0.42 0.43 0.44 0.48 0.51 0.52 0.50 0.54 0.53 0.56

0.55 0.64 0.52 0.64 0.50 0.61 0.53 0.59 0.50 0.57 0.50 0.57 0.50 0.58 0.50 0.57 0.52 0.64 0.50 0.63 0.59 0.67 0.56 0.68 0.60 0.71 0.63 0.79 0.67 0.88 0.79 0.96 0.85 1.00 0.83 1.10

0.63 0.73 0.56 0.67 0.52 0.62 0.50 0.57 0.48 0.58 0.47 0.60 0.50 0.60 0.50 0.58 0.50 0.59 0.55 0.70 0.50 0.67 0.56 0.70 0.61 0.76 0.60 0.71 0.62 0.77 0.66 0.83 0.63 0.81 0.73 0.89

0.76 0.93 - 0.73 0.84 0.87 0.75 0.88 0.92 0.66 0.77 0.84 0.67 0.78 0.82 0.69 0.80 0.94 0.67 0.88 1.00 0.75 0.91 1.00 0.75 0.87 1.00 0.77 0.90 1.00 0.86 1.00 0.83 1.00 0.89 1.19 0.92 1.05 1.11 1.36 1.10 1.22 1.27 1.41 1.40 1.69

0.85 1.00 0.79 0.94 0.74 0.93 0.67 0.83 0.69 0.77 0.73 0.83 0.71 0.82 0.75 0.89 0.74 0.94 0.92 1.11 0.92 1.10 0.87 1.10 0.91 1.06 0.98 1.12 0.93 1.08 1.06 1.20 0.98 1.18 1.10 1.23

1.15 1.29

-

1.00 1.06 - -

0.92 1.04

1.05 1.18

-

- 1.19 1.27

there is a decrease by age 17 to around the reference median.

Average triceps thickness is very close to the reference medians for both boys and girls up through the preschool period (Fig. 2). At about age 6 or 7 years, both curves begin increasing to above the 50th percentile and remain there to maturity, although there is a slight decrease in girls at the end of adoles- cence that leaves them just below the refer- ence median at age 17. Median values for the subscapular skinfold tend to approximate the 50th percentile through the preschool years and then to increase close to the 75th percentile through adolescence in both gen- ders (Fig. 3).

Median values for the ratio of the subscap- ular to the triceps skinfold thickness for both boys and girls are shown in Figure 4. Exam- ination of the values over the age range shows that this ratio stays consistently be- low 1.0 except for 16- and 17-year-old boys, in which cases the median is equal to or just slightly greater than 1 .O. Mexican-American boys and girls both generally grow between the 50th and 75th percentile of the reference curves, with girls attaining slightly higher values.

Figures 5-8 present median values com- pared with the HES Cycle I11 percentiles for the adolescents only. Among adolescents, values for the suprailiac skinfold are be-

636 H. KAPLOWITZ ET AL.

TABLE 4 . Sample sizes, minimum and maximum ualues, means, standard deuiations, and percentiles for the trunk/extremity ratio for Mexican-Americans from the Hispanic Health

and Nutrition Examination Survey (HHANES)

Percentiles Minimum Maximum Age N value value Mean SD 5th 10th 25th 50th 75th 90th 95th

Males 0 57

104 111 130 118 116

0.34 0.31 0.32 0.37 0.38 0.22 0.35 0.33 0.40 0.34 0.44 0.45 0.30 0.46 0.57 0.64 0.74 0.62

0.38 0.35 0.32 0.40 0.31 0.34 0.31 0.36

0.81 0.92 1.21 1.24 1.19 2.40

0.57 0.12 0.12 0.16 0.16 0.17 0.24 0.21

0.43 0.43 0.46 0.45 0.48 0.47 0.48 0.49 0.48 0.57 0.60 0.66 0.64 0.74 0.80 0.91 0.86 0.96

0.44 0.43 0.46 0.46 0.46 0.48 0.46 0.50 0.53 0.50 0.60 0.57 0.63 0.63

0.48 0.49 0.53 0.54 0.54 0.54 0.58 0.60

0.54 0.65 0.66 0.64

0.72 - 0.72 0.83 0.85 0.94 0.83 1.02 0.89 1.04 0.88 1.09 1.00 1.04 1.09 1.21

- 0.40 0.44 0.42 0.45 0.44 0.45 0.44 0.44 0.50

0.60 0.56

-

- -

~~

0.57 0.64 0.65

1 2 3 4 5 6 7 8 9

10

0.61 0.73 0.63 0.73 0.63 0.78 0.67

0.67 0.73

0.63 0.73 0.71 0.88 0.74 0.88 0.76 1.02 0.82 1.00 0.91 1.18 0.95 1.17 0.97 1.21 0.98 1.16

110 110 102

1.55 1.43 1.88 1.53

0.76 0.82 0.85

0.23 0.27 0.63

0.68 0.75

1.14 1.30 1.19 1.29 106

88 115 114 97 97 69 76 71

63

0.24 0.27 0.29 0.33 0.26 0.36 0.31 0.47 0.48

0.14 0.16

1.55 1.85 2.29

0.94 0.99 1.02 1.03

1.34 - 1.41 1.50 1.49 1.61 1.38 - 1.64 - 1.65 - 1.91 - 2.24 -

0.81 - 0.86 0.93 0.86 1.00 0.84 - 0.91 - 1.00 1.17 1.00 1.13 1.11 - 1.12 1.25 1.29 1.44 1.32 - 1.29 1.51 1.35 1.46

1.41 - 1.32 - 1.36 - 1.38 -

1.34 -

11 12 13

0.77 0.78 0.88 0.99 1.05 1.18 1.14

0.50 0.49 0.56 0.53 0.54 0.57 0.55 0.58 0.57 0.67 0.66 0.73 0.77 0.76 0.78 0.81 0.83 0.86

1.79 2.46 1.23

1.26 1.21 1.44 1.21 1.47 1.38 1.63

14 15 16 17

Females 0

2.19 3.04 3.15

1.02

1.44 1.52

0.60 0.62 0.66 0.65 0.68 0.70 0.71 0.75

1.47 1.85

0.58 0.69 0.61 0.72 0.65 0.75 0.62 0.74 0.66 0.76 0.66 0.80 0.68 0.83 0.67 0.88 0.69 0.85 0.93 1.13 0.83 1.15 0.89 1.05 0.97 1.13 0.92 1.05

-

0.40 0.41 - -

0.43 0.43

0.50 0.48

0.51 0.58

-

-

-

119 118 96

1.06 1.11 1.38

0.16 0.17 0.19 4

5 6 7

96 109 118 96

1.25 1.30 1.77 1.45

0.21 0.23 0.24

8 107 0.41 1.43 0.75 0.23 9 125 0.35 1.90 0.92 0.30

10 94 0.44 1.76 0.91 0.30 11 115 0.34 1.96 0.92 0.30 12 103 0.43 1.91 0.97 0.28 13 89 0.48 1.67 0.94 0.27 14 75 0.47 1.74 0.99 0.26 15 85 0.54 2.30 1.01 0.27 16 99 0.53 1.89 1.01 0.29 17 75 0.42 1.90 1.04 0.27

Dashes indicate insufficient sample size (see Materials and Methods).

1.00 1.12 0.97 1.18 0.98 1.17

0.64 0.70 0.67 0.75 1.03 1.22

tween the 50th and 75th percentiles of the HES reference curves for boys and at the 75th percentile for girls (Fig. 5) . Boys grow slightly below the HES median for the me- dial calf skinfold through adolescence (Fig. 61, while girls are slightly above the 50th percentile from 12 to 14 years and below it from then on.

The trunklextremity index for both boys and girls steadily increases with age (al- though much less so in adolescent girls), with both genders reaching 1.0 at about 14 years of age (Fig. 7). Gender differences are small until the adolescent period, when boys tend steadily to become much more central- ized than girls. Both male and female adoles-

cents grow consistently at or above the 75th percentile of the HES data.

Both Mexican-American boys and girls tend toward an upper body distribution of subcutaneous fat from birth through adoles- cence, as assessed by the upperflower body index. Median values are greater than 1.0 at birth and continue to increase up to about 2.9 in males and 2.0 in females by maturity. Gender differences are small until adoles- cence, although there is a consistent trend toward a more upper body distribution in males (Fig. 8). Adolescent males grow at or above the 90th percentile of the HES refer- ence. Female adolescents grow similarly, but stay at or just below the 90th percentile.

FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS 637

TABLE 5. Sample sizes, minimum and maximum values, means, standard deviations, and percentiles for the upper/lower body ratio for Mexican-Americans from the Hispanic Health

and Nutrition Examination Survey (HHANES)

Minimum Maximum Percentiles Age N values values Mean SD 5th 10th 25th 50th 75th 90th 95th

Males 0 57 1 104 2 111 3 130 4 118 5 116 6 110 7 110 8 102 9 106

10 88 11 115 12 114 13 97 14 97 15 69 16 76 17 71

0 63 I 119 2 118 3 96 4 96 5 109 6 118 7 96 8 107 9 125

10 94 11 115 12 103 13 89 14 75

Females

0.75 0.86 0.43 1.00 1 .oo 0.86 0.88 1.07 0.96 0.88 1.09 0.92 0.90 1.11 1.14 1.24 1.15 1.38

0.65 0.76 0.83 0.90 0.91 0.94 0.95 0.95 1.00 0.95 0.85 0.97 0.97 0.86 0.91

1.21 1.36 1.59 1.79 1.80 1.89 1.99 1.97 2.01 2.03 2.08 2.08 2.07 1.99 2.42 2.48 2.70 3.08

1.33 1.31 1.58 1.63 0.68 1.73 1.82 1.77 1.81 1.95 2.00 1.86 1.92 1.92 2.03

15 85 1.15 2.10 16 99 0.96 4.11 2.15 17 75 1.07 3.58 2.04

1.76 2.64 2.71 3.08 3.30 6.00 3.40 3.71 3.56 6.25 4.00 4.95 5.33 3.60 4.85 4.50 4.89 6.15

2.20 2.44 2.69 2.80 2.71 2.86 4.33 3.22 3.14 4.13 4.00 7.40 4.73 4.87 4.21 6.83

0.21 -1

0.31 0.98 0.38 1.00 0.38 1.19 0.41 1.19 0.62 1.14 0.49 1.28 0.45 1.29 0.55 1.24 0.72 1.24 0.58 - 0.62 1.33 0.66 1.27 0.50 - 0.75 - 0.73 - 0.82 - 1.00 -

0.32 - 0.27 0.94 0.36 0.96 0.37 - 0.37 - 0.41 1.09 0.48 1.17 0.43 - 0.43 1.23 0.51 1.21 0.60 - 0.72 1.13 0.61 1.21 0.68 - 0.60 - 0.73 - 0.62 -

0.98 1.04 1.15 1.36 1.33 1.32 1.39 1.46 1.38 1.33 1.50 1.48 1.36 1.37 1.56 1.67 1.67 1.92

0.95 0.97 1.11 1.20 1.30 1.19 1.21 1.28 1.31 1.35 1.41 1.22 1.33 1.20 1.41 1.47 1.46

0.54 - I .35 'Dashes indicate insufficient sample size (see Materials and Methods).

1.06 1.11 1.29 1.54 1.50 1.56 1.61 1.64 1.63 1.57 1.67 1.68 1.61 1.60 1.80 1.92 2.12 2.30

1.14 1.14 1.30 1.32 1.43 1.48 1.56 1.47 1.47 1.60 1.65 1.44 1.51 1.41 1.61 1.65 1.64

1.21 1.33 1.58 1.77 1.78 1.78 1.90 1.92 1.92 1.87 1.94 1.99 1.95 1.93 2.33 2.35 2.58 2.85

1.25 1.27 1.60 1.59 1.67 1.73 1.80 1.74 1.80 1.93 1.86 1.81 1.79 1.80 1.97 1.98 2.05

1.71 2.00

1.32 1.52 1.88 2.00 2.00 1.09 2.31 2.25 2.39 2.36 2.43 2.36 2.38 2.40 2.82 2.88 3.25 3.67

1.50 1.47 1.81 1.83 1.93 1.96 2.08 2.00 2.12 2.25 2.21 2.08 2.07 2.24 2.33 2.41 2.64

1.50 1.77 2.07 2.35 2.29 2.50 2.62 2.50 2.86 2.88 2.93 2.71 2.88 2.60 3.60 3.67 3.78 4.43

1.83 1.67 2.06 2.08 2.16 2.26 2.33 2.32 2.40 2.50 3.00 2.50 2.86 2.75 2.98 2.70 2.98

- 1.89 2.17 2.50 2.46 2.89 3.00 2.75 3.00 3.17

3.08 3.20

-

- - - - -

- 1.80 2.17 - -

2.58 2.58

2.61 2.83

3.00 3.29

-

-

- - - - - 2.36 2.90

TABLE 6. Sample sizes, means, and standard deviations by gender and BMI quartiles for indices of fa t distribution

Males Females N Mean SD N Mean SD

BMI < 25th percentile Trunklextremity 451 0.67 0.190 448 0.66 0.179 Upper/lower 452 1.90 0.562 448 1.72 0.469 Subscapular/triceps 452 0.61 0.184 450 0.59 0.150

Trunklextremity 448 0.74 0.243 443 0.70 0.219 Upper/lower 448 1.91 0.592 443 1.64 0.506 Subscapular/triceps 449 0.62 0.180 443 0.63 0.206

Trunk/extremity 448 0.89 0.362 442 0.86 0.259 Upper /lower 448 1.93 0.726 442 1.79 0.531 Subscapular/triceps 448 0.73 0.257 443 0.74 0.229

Trunk/extremity 448 1.23 0.385 443 1.06 0.268 Upper /lower 448 2.25 0.773 444 2.1 1 0.626 Subscapular/triceps 449 0.92 0.324 444 0.90 0.254

25th percentile I BMI < 50th percentile

50th percentile I BMI < 75th percentile

BMI > 75th percentile

638 H. KAPLOWITZ ET AL

26 - 25 -

21

,------ # -- MALES

1 4 -

1 3 - --_______------ --.____.-+*

---._ - -

25 A

13 I ' l ' I ' I ' l ~ l . l ~ l ' l ' I ~ I ' I ' l ' , ' I ' l '

2 3 4 5 6 7 8 9 1 0 1 1 12 1 3 1 4 15 1 6 1 7 1 8 1 9

Age (years)

Fig. 1 . Median body mass index (BMI) by age and gender for Mexican-American children and adolescents

from the HHANES percentiles compared with the NHAh'ES I1 percentiles for non-Hispanic whites.

639 FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS

2 6 MALES

0 1 2 3 4 5 6 7 8 9 10 11 1 2 13 1 4 1 5 16 17 18 19

1 - 1 ' 1 . I 1 . ( I , . I r I ' , . ( . l . l . , . , ,

0 1 2 3 4 5 6 7 8 9 10 11 1 2 13 1 4 15 1 6 17 1 8 19 b ' I . 1 '

Ago (yews)

Fig. 2. Median triceps skinfold thickness by age and gender for Mexican-American children and adolescents

from the HHANES percentiles compared with the NHANES I1 percentiles for non-Hispanic whites.

640 H. KAPLOWITZ ET AL.

30

MALES

2 4

0 1 ' 1 ~ l ' 1 ~ l ' l ' 1 ' 1 ~ 1 ' 1 ' l ~ I ~ I ' I ~ ~ ' J ~ ~ ' J ~

Age (years)

30

0 1 ' / ~ / ' 1 ~ 1 ' 1 ' 1 ' l ~ l ' 1 ' I ' I ~ l ~ I ~ / ~ 1 . 1 ' 1 '

Age (years)

Fig. 3. Median subscapular skinfold thickness by age and gender for Mexican-American children and adoles-

cents from the HHANES percentiles compared with the NHANES I1 percentiles for non-Hispanic whites.

FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS 64 1 1.7 **

1 - 6 * ,.,.. t

MALES

0 1 2 3 4 5 6 7 8 9 10 11 1 2 13 14 1 5 16 17 18 1 9

Age (years)

1.7 -I

p 1.1

5 1.0

4 0.9 + 0.8

c

vl

I - > 0.7

a 0.6 - 3

u 0 . 5

3 vl 0.4

0.3

0.2

0.1

0.0 i ' l ~ l ' l ~ l ~ , ~ l ~ i ' l ' i ~ ~ ~ ~ ~ l ~ l ~ , . ~ ~ ~ ~ ~ ~

0 1 2 3 4 5 6 7 8 9 1 0 11 1 2 1 3 14 15 1 6 17 18 1 9

Agq (yecrs)

Fig. 4. Median subscapular/triceps ratio by age and gender for Mexican-American children and adolescents

from the HHANES percentiles compared with the NHANES I1 percentiles for non-Hispanic whites.

642 H. KAPLOWITZ ET AL.

30.1

- 2 0 . E , E v 1 8 - B 2 1 6 - - x * 1 4 - 0

= 1 2 - *

0

- e , 2 1 0 - a

..... ,.,' .................................... .................................. ," I.-.-------. ........... ...... MALES

...... 2 6 ............

Wlh ......... ........ ......... .......... .______.------ ----_ -.-___ ------.._._____ ----______ ..................................................

4 - 10th ................. ______----- ...........................................

,-.---------------------------~---------------------~----~-*----

2 1 6 - - 0 - - Y * 1 4 -

- 1 OL a 1 0 -

0 - 6

0 I ' I ' I ~ J ' I ' I * I . I ' I . I '

12.0 13 .0 14 .0 15 .0 1 6 . 0 17.0

Age (years)

30

...................... *- lo th

---___ I--__ ---__ ---__ .........................

............. ______________--_-_--- .................... ............

25th - - - - - - - .......................................... ...........................................

................................... ------ - - - - - - - _ _ _ _ _ ___------ ....... ___--- ____---- ............................................. ,011

............................ ________. ------ 4 -

2 -

643 FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS

26

0 l ' l ' l ~ , ~ , * , ~ , * l ~ ~ ~ , ~

12.0 13.0 14.0 15 .0 16.0 17.0

Age (years)

32 $

12 .0 1 3 . 0 14 .0 15 .0 16 .0 17.0

Age (years)

Fig. 6. Median medial calf skinfold thickness by age and gender for Mexican-American adolescents from the

HHANES percentiles compared with the HES cycle I11 percentiles for non-Hispanic whites.

644 H. KAPLOWITZ ET AL.

2.0 4 1.9

1.8

1 .7

1.6

1.5

1 .4

x 1.3

c 1 .2 D Q - =" 1.1

z 0.9

2 0.8

g 1.0 c

\

0.7

0.6

0.5

0.4

0.3

0 . 2

0.1

0.0 l ' l ' - l ~ " ~ ' l ' l ' l ~ l ' l '

12.0 13.0 14.0 1 5 . 0 16.0 17 .0

Age (years)

Aga (years)

Fig. 7. Median trunklextremity index by age and gender for Mexican-American adolescents from the

HHANES percentiles compared with the HES cycle I11 percentiles for non-Hispanic whites.

FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS 645 3.5

3.0

x Q

v

z -0 0

L 0

2.5

m

: '=- 2.0 -1

n n 3

1 . 5

1 .o

3.5

3.0

X 0

0 2.5

h U 0 m

L 0

: 3 2.0 2

a 3 n

1.5

1 . o

MALES

1 2 . 0 13 .0 14 .0 15.0 16 .0 1 7 . 0

Age (yeors)

FEMALES

1 2 . 0 13 .0 1 4 . 0 15 .0 16.0 17 .0

Ago (yecrs)

Fig. 8. Median upperAower body index by age and gender for Mexican-American adolescents from the

HHANES percentiles compared with the HES cycle 111 percentiles for non-Hispanic whites.

646 H. KAPLOWITZ ET AL.

DISCUSSION

Previous studies indicate that Mexican- American children are shorter, but rela- tively heavier, than their non-Hispanic white counterparts and that this difference in relative weight is becoming more appar- ent with time (Kautz and Harrison, 1981; Martorell et al., 1987,1989; Yanochik-Owen and White, 1977; Dewey et al., 1983; Malina et al., 1983, 1987; Zavaleta and Malina, 1982). Furthermore, the greater weight for height of Mexican-Americans appears to be due to positive secular changes in fat rather than to lean body mass and, more specifi- cally, to increases in fat deposited on the upper trunk (Malina et al., 1986,1987; Mar- torell et al., 1987, 1988a; Haf'fner et al., 198613; Mueller, 1988; Guinn et al., 1986). Table 6 indicates the relationship between body size, as measured by the body mass index, and the various indices of fat distribu- tion. It can be seen that as fatness increases, individuals become more centralized in their pattern of adiposity. Evidence provided by Martorell et al. (1988a) supports the theory that this is indeed a real difference and not a result of confounding caused by greater trunk length in Hispanics, as their findings found little difference in trunk length when comparing Mexican-Americans from the HHANES with non-Hispanic white children from the NHANES 11.

Our results are consistent with these ear- lier findings. Mexican-American children from the Hispanic Health and Nutrition Ex- amination Survey (HHANES) have higher BMIs, higher triceps, subscapular, and su- prailiac skinfold measures (at least during adolescence), and higher values for all body fat distribution indices (subscapular/triceps, trunwextremity, and upperflower body) than do non-Hispanic white children. Mexi- can-Americans also have reduced leg fat as measured by the medial calf skinfold thick- ness.

Mexican-American boys begin this trend toward overweight prior to the onset of ado- lescence, as early as 11 years of age. How- ever, in terms of the relative distribution of adipose tissue, a centralized or upper body obesity pattern emerges as early as 8 years of age. Girls follow a similar pattern, but begin increasing in both overall adiposity and up- per body obesity 3 to 4 years earlier than do boys. While it is clear that there are at least some positive secular changes among non- Hispanic white children as well, the star-

tling differences in fat distribution between the Mexican-American and non-Hispanic white subgroups (Figs. 7 and 8) can probably not be completely explained by secular trend in the reference populations.

Haffner and colleagues (1987) suggest that, since indices of centralized adiposity (e.g., subscapular/triceps ratio, trunldex- tremity index) and upper body obesity (e.g., upperflower body index or the waist to hip or waist to thigh circumference ratios used by many) are relatively uncorrelated with each other, these indices may measure different aspects of fat distribution. Although these indices are significantly correlated in many of the age and gender groups in our data (as high as 0.7 in older girls), our results still indirectly support his theory since the differ- ences between the Mexican-Americans and non-Hispanic whites are much more dra- matic for the upperflower body index than for the trunWextremity index. While the two indices used in these analyses may overlap to some degree, it does seem that informa- tion is lost if only the trunk-extremity con- trast is examined. How this should be interpreted in terms of increased risk of disease is still very unclear, however. For example, Haffner et al. (1987) found both measures to be associated with type I1 non- insulin-dependent diabetes mellitus, low HDL cholesterol levels, and high triglyceride levels, but upper body adiposity seems to be more predictive than is centralized adipos- ity. However, their index of centralized adi- posity was composed of upper body skinfold thicknesses only (subscapular/triceps ratio), while the measure of upper body adiposity was the ratio of two circumferences, specifi- cally, the waist and hip. As they discuss, the skinfold thickness ratio reflects fat only on the upper trunk and only subcutaneous fat, which may be less metabolically active than visceral fat, while the circumference ratio includes both visceral and subcutaneous fat (Haffner et al., 1987). In other words, the discrepancy found between the two indices in the strength of their associations with disease risk may be due not to differences between measures of central versus upper body adiposity per se, but to the choice of anthropometric measures (e.g., skinfold thicknesses versus circumferences) used to construct the indices. The present study uses only skinfold measures to construct the var- ious indices, but whether these indices are differentially associated with disease risk remains to be established. Regardless of how

FATNESS AND FAT DISTRIBUTION IN MEXICAN-AMERICANS 647

the distribution of body fat is measured, however, it is very probable that the greater centralized and upper body adiposity of Mex- ican-Americans as compared with the non- Hispanic white population is associated with relatively large increases in risk of certain chronic diseases in later life (Haffner et al., 1986a-c; Reichley et al., 1987; Stern and Haffner, 1986). Evidence for a decrease in this risk with environmentally induced change in fatness and fat distribution, through life-style changes, remains to be found (Haffner et al., 1986b; Stern et al., 1982). This is due in part to the lack of understanding of why the Mexican-Amer- ican subgroup is fatter than their non-His- panic white counterparts. For example, is caloric intake excessive relative to expendi- ture? Are Mexican-Americans genetically predisposed to obesity, particularly upper body obesity, and also to certain diseases, such as type I1 diabetes? Or, as some evi- dence suggests, is this pattern explained by a complex interaction between some form of genetic predisposition and environmental variables, such as diet and activity patterns? Further research is necessary to clarify these relationships.

Regardless, Mexican-American children are fat, and this represents a serious public health problem. A prudent course of action would be the promotion of healthy dietary patterns and greater physical activity through the schools and the population at large.

ACKNOWLEDGMENTS The authors thank Katherine Baisden,

MA, for help with data management and Victor Bandeira de Mello, PhD, for invalu- able assistance with statistical computing and graphics. They also acknowledge NCHS as the original data source for this research. This work was supported by grant MCJ- 060518-01-0, Maternal and Child Health Re- search grants program, Bureau of Health Care Delivery and Assistance, Rockville, Maryland, and by grant R01-HD22440 from NICHHD, Bethesda, Maryland.

LITERATURE CITED Bailey SM, Gershoff SN, McGandy RB, Nondasuta A,

and Tantiwongse P (1985) Subcutaneous fat remodel- lin in Southeast Asian infants and children. Am. J . Phys. Anthropol. 68:123-130.

Blair D, Habicht J-P, Sims EAH, et al. (1984) Evidence for an increased risk for hypertension with centrally located body fat and the effect of race and sex on this risk. Am. J. Epidemiol. 119:526-540.

Bogin B, and MacVean RB (198l)Nutritional and biolog- ical determinants of body fat patterning in urban Guatemalan children. Hum. Biol. 53(2):259-268.

Dewey KG, Chavez MN, Gauthier CL, Jones LB, and Ramirez RE (1983) Anthropometry of Mexican-Amer- ican migrant children in Northern California. Am. J. Clin. Nutr. 37:828-833.

Flegal KM, Harlan WR, and Landis JR (1988a) Secular trends in body mass index and skinfold thickness with socioeconomic factors in young adult men. Am. J . Clin. Nutr. 48:544-551.

Flegal KM, Harlan WR, and Landis JR (1988b) Secular trends in body mass index and skinfold thickness with socioeconomic factors in young adult women. Am. J. Clin. Nutr. 48.535543.

Frisancho AFC, and Flegel PN (1982) Advanced matura- tion associated with centripetal fat pattern. Hum. Biol. 54:717-727.

Guinn B, Semper T, and Crofts A (1986) Anthropometric comparisons among low-income Mexican American children aged 10 through 14. J. Am. Diet. Assoc. 86(1):57-60.

Habicht J-P, Yarbrough C, and Martorell R (1979) An- thropometric field methods: Criteria for selection. In DF Jelliffe and EFP Jelliffe (eds.): Nutrition and Growth. New York: Plenum Press, pp. 365487.

Haffner SM, Stern MP, Hazuda HP, Pugh J , and Patter- son JK (1986a) Hyperinsulinemia in a population at high risk for non-insulin-dependent diabetes mellitus. N. Engl. J. Med. 315f4):220-224.

Haffner SM, Stem MP, Hazuda HP, Pugh J , and Patter- son JK (1987) Do upper-body and centralized adiposity measure different aspects of regional body fat distribu- tion? Relationship to non-insulin-dependent diabetes mellitus, lipids and lipoproteins. Diabetes 36:43-51.

Hafber SM, Stem MP, Hazuda HP, Pugh J , Patterson JK, and Malina RM (198613) Upper body and central- ized adiposity in Mexican American and non-Hispanic whites: Relationship to body mass index and other behavioral and demographic variables. Int. J . Obesity 10:493-502.

HafTner SM, StemMP, HazudaHP, Rosenthal M, Knapp JA, and Malina RM (1986~) Role of obesity and fat distribution in non-insulin-dependent diabetes melli- tus in Mexican American and non-Hispanic infants. Diabetes Care 9(2):153-161.

Joos SK, Mueller WH, Hanis CL, and Schull WJ (1984) Diabetes alert study: Weight history and upper body obesity in diabetic and non-diabetic Mexican Ameri- can adults. Ann. Hum. Biol. II:167-171.

Kaplowitz HJ, Mueller WH, Selwyn BJ, Malina RM, Bailey DA, and Mirwald RL (1987) Sensitivities, spec- ificities, and positive predictive values of simple indi- ces of body fat distribution. Hum. Biol. 59(5):809-825.

Kautz L, and Harrison GG (1981) Comparison of body proportions of one-year-old Mexican American and Anglo children. Am. J. Phys. Anthropol. 71(3): 280-282.

Lapidus L, Bengtsson C, Larsson B, et al. (1984) Distri- bution of adipose tissue and risk of cardiovascular disease and death: A 12 year follow up of participants in the population study of women in Gothenburg, Sweden. Br. Med. J. 289:1257-1261.

Malina RM, Little BB, Stem MP, Gaskill SP, and Ha- zuda HP (1983) Ethnic and social class diierences in selected anthropometric characteristics of Mexican American and Anglo adults: The San Antonio heart study. Hum. Biol. 55:867-883.

Malina RM, Zavaleta AN, and Little BB (1986) Esti- mated overweight and obesity in Mexican Amencan school children. Int. J. Obesity 10:483-491.

648 H. KAPLOW

MalinaRM, Zavaleta AN, andLittleBB (1987)Body size, fatness, and leanness of Mexican American children in Brownsville, Texas: Changes between 1972 and 1983. Am. J. Phys. Anthropol. 77(5):573-577.

Martorell R, Malina RM, Castillo RO, Mendoza FS, and Pawson IG (1988a) Body proportions in three ethnic groups: Children and youths 2-17 years in NHANES I1 and HHANES. Hum. Biol. 60(2):205-222.

Martorell R, Mendoza FS, and Castillo RO Genetic and environmental determinants of growth in Mexican- Americans. Pediatrics (in press).

Martorell R, Mendoza FS, Castillo RO, Pawson IG, and Budge CC (1987) The short and plump physique of Mexican American children. Am. J. Phys. Anthropol. 73:475487.

Martorell R, Mendoza F, Mueller WH, and Pawson IG (1988b) Which side to measure: Right or left? In TG Lohman, AF Roche, and R Martorell (eds.): Anthropo- metric Standardization Reference Manual. Cham- paign, I L Human Kinetics Books, pp. 87-91.

McDowell A, Engle A, Massey JF, et al. (1981) Plan and Operation of the Second National Health and Nutri- tion Examination Survey 1976-1980. Washington, D.C.: US. Government Printing Office, Public Health Service, DHHS Publication No. (PHS) 81-1317. Vital and Health Statistics, Series 1, No. 15.

Mueller WH (19883 Ethnic differences in fat distribution during growth. In C Bouchard and FE Johnston (eds.): Current Topics in Nutrition and Disease, Vol. 17: Fat Distribution During Growth and Later Health Out- comes. New York Alan R. Liss, Inc., pp. 127-145.

Mueller WH, Hanis CL, Zavaleta AN, Eichner J, and Schull WJ (1984) The Diabetes Alert Study: Growth, fatness, fat patterning, adolescent through adulthood in Mexican American. Am. J. Phys. Anthropol.

Mueller WH, and Stallones L (1981) Anatomical distri- 64:389-399.

IT2 ET AL.

bution of subcutaneous fat: Skinfold site choice and construction of indices. Hum. Biol. 53:321-335.

Najjar MF, Kuczmarksi RJ (1989) Anthropometric data and prevalence of overweight for Hispanics: 1982-84. National Center for Health Statistics. Vital Health Stat. ll(239).

National Center for Health Statistics (1985) Plan and Operation of the Hispanic Health and Nutrition Ex- amination Survey 1982-84. DHS Publication No. (PHS) 85-1321. Hyattville, MD: US. Department of Health and Human Services, Public Health Service, National Center for Health Statistics.

Reichley KB, Mueller WH, Hanis CL, Joos SK, Tulloch BR, Barton S, and Schull WJ (1987) Centralized obe- sity and cardiovascular disease risk in Mexican Amer- icans. Am. J. Epidemiol. 125(3):373-386.

Roche AF, and Baumgartner RN (1988) Tracking in fat distribution during growth. In C Bouchard and FE Johnston (eds.): Current Topics in Nutrition and Dis- ease, Vol. 17: Fat Distribution During Growth and Later Health Outcomes. New York Alan R. Liss, Inc.,

Stern M p , and Haffner SM (1986) Body fat distribution and hyperinsulinemia as risk factors for diabetes and cardiovascular disease. Arteriosclerosis 6:123-130.

Stem MP, Pugh JA, Gaskill SP, and Hazuda HP (1982) Knowledge, attitudes, and behavior related to obesity and dieting in Mexican Americans and Anglos: The

pp. 147-162.

San Antkio Heart Study. Am. J. Eiidemiol. 11.5/6):917-928. ~ ~ _ I

Yanochik-Owen A, and White M (1977) Nutrition sur- veillance in Arizona: Selected anthropometric and laboratory observations among Mexican-American children. Am. J. Public Health 67:151-154.

Zavaleta AN, and Malina RM (1982) Growth and body composition of Mexican American boys 9-14 years of age. Am. J. Phys. Anthropol., 57:261-271.