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Background: Little is known about the association of contributors of total water intake with dietary characteristics in US children. Objective: We examined intakes of total water and its contributors and their associations with diet and meal reporting in children and adolescents. Design: Dietary data for children 2-19 y of age (n = 3978) from the National Health and Nutrition Examination Survey 2005-2006 were used to compute usual intake of total water. The association of total water and its contributors with sociodemographic characteristics and dietary and meal attributes was examined by using multiple regression analysis. Results: The adjusted mean intakes of total water in Americans aged 2-5, 6-1l, and 12-19 y were 1.4, 1.6, and 2.4 L, respectively. The mean usual intake of total water was generally less than the Adequate Intake; overall, more boys reported intakes of at least the Adequate Intake. The percentage of total water intake from plain water increased with age. Plain water intake was inversely associated with the intake of beverage moisture and the energy density of foods; conversely, beverage moisture was positively associated with dietary energy, fat, and the energy density of foods. Associations of water contributors with meal patterns (number of eating occasions, reporting of breakfast or snack) were inconsistent across age groups. Nearly 80% of food moisture, >66% of beverage moisture, and [approximately equal to]30% of plain water were reported with main meals. Conclusions: Intake of total water over 24 h from different contributors varied by age. Qualitative differences in dietary intake in association with the amount of plain water and beverage moisture in the recalls were observed. American children and adolescents consumed more than two-thirds of their daily beverages with main meals. Am J Clin Nutr 2010;92:887-96. doi: 10.3945/ajcn.2010.29708.

Background: Body mass index (BMI)--for-age has been recommended as a screening test for excess adiposity in children and adolescents. Objective: We quantified the performance of standard categories of BMI-for-age relative to the population prevalence of high adiposity in children and adolescents overall and by race-ethnic group in a nationally representative US population sample by using definitions of high adiposity that are consistent with expert committee recommendations. Design: Percentage body fat in 8821 children and adolescents aged 8-19 y was measured by using dual-energy X-ray absorptiometry in 1999-2004 as part of a health examination survey. Results: With the use of several different cutoffs for percentage fat to define high adiposity, most children with high BMI-for-age ([greater than or equal to]95th percentile of the growth charts) had high adiposity, and few children with normal BMI-for-age ( Conclusions: Current BMI cutoffs can identify a high prevalence of high adiposity in children with high BMI-for-age and a low prevalence of high adiposity in children with normal BMI-for-age. By these adiposity measures, less than one-half of children with intermediate BMIs-for-age (85th to doi: 10.3945/ajcn.2009.28589.

Background: Estimates of obesity-associated deaths in the United States for 1991 were published by Allison et al (JAMA 1999;282: 1530-8) and subsequently for 2000 by Mokdad et al (JAMA 2004; 291:1238-45). Flegal et al (JAMA 2005;293:1861-7) then published lower estimates of obesity-associated deaths for 2000. All 3 studies incorporated data from the first National Health and Nutrition Examination Survey (NHANES I). Objective: The objective was to clarify the effects of methodologic differences between the 3 studies in estimates of obesity-associated deaths in the US population by using NHANES I hazard ratios. Design: The earlier reports used imputed smoking data for much of the NHANES I sample rather than the available reported data and applied a method of calculating attributable fractions that did not adjust for the effects of age, sex, and smoking on mortality in the target US population and did not account for effect modification by age. The effects of these and other methodologic factors were examined. Results: The NHANES I hazard ratios in the earlier reports were too low, probably because of the imputed smoking data. The low hazard ratios obscured the magnitude and direction of the bias arising from the incompletely adjusted attributable fraction method. When corrected hazard ratios were used, the incompletely adjusted attributable fraction method overestimated obesity-associated mortality in the target population by > 100,000 deaths. Conclusion: Methodologic sources of bias in the reports by Allison et al and Mokdad et al include the assessment of smoking status in NHANES I and the method of calculating attributable fractions. Am J Clin Nutr 2010;91:519-27. doi: 10.3945/ajcn.2009.28222.

Background: There is a surprising paucity of studies that have systematically examined the correlates of water intake in the US population. Objective: The objective was to examine the association of contributors of water intake with dietary characteristics, meal consumption, and body weight in the US population. Design: We used 24-h dietary recall data from the National Health and Nutrition Examination Survey (NHANES) 1999-2004 (n = 12,283) and the NHANES 2005-2006 (n = 4112) to examine the independent association of intakes of plain water, beverage moisture, food moisture, and total water with sociodemographic factors, dietary characteristics (energy, nutrients, diet quality, and energy density), and meal patterns (number of eating episodes, mention of breakfast or snack) by using multiple regression methods. Results: In 2005-2006, American adults reported consuming 3.18 L of total water within the previous 24 h (in 1999-2004, estimated total water intake was 3.35 L), with plain water and beverages contributing 33% and 48% of the total, respectively. Plain water intake was unrelated to the intake of energy and body mass index but was positively related to dietary fiber and inversely related to beverages, sugars, and the energy density of foods; these associations were in the opposite direction for beverage moisture intake. Total water intake was inversely related to energy from fat and energy density but positively related to dietary fiber, caffeine, alcohol, and diet quality. The number of eating episodes predicted higher beverage and food moisture and total water intakes. A higher body mass index predicted higher intakes of beverage moisture and total water. Conclusion: Various contributors of total water intake differed in their association with dietary characteristics and body weight in the adult US population.

Background: Estimates of excess mortality associated with body mass index (BMI; in kg/[m.sup.2]) have been calculated for the US population. Objective: The objective of this article is to compare the excess mortality associated with BMI levels to the excess mortality associated with other anthropometric variables. Design: For the 1988-1994 Third National Health and Nutrition Examination Survey, estimates of excess deaths were calculated for standard BMI levels and for comparable levels of percentage body fat, waist circumference, hip and arm circumferences, waist-hip ratio, the sum of 4 skinfold thicknesses, and waist-stature ratio. The outcome measure is the percentage of deaths in the full sample in excess of those predicted for the reference category. Results: For the level equivalent to BMI < 18.5, estimates of excess deaths ranged from 0.3% for waist-hip ratio to 2.4% for percentage body fat. All except waist circumference, waist-hip ratio, and waist-stature ratio were significantly greater than zero (P < 0.05). For the level equivalent to BMI 25 to Conclusion: In this population-based study, attributable fractions of deaths were similar across measures.

Background: Body mass index (BMI), waist circumference (WC), and the waist-stature ratio (WSR) are considered to be possible proxies for adiposity. Objective: The objective was to investigate the relations between BMI, WC, WSR, and percentage body fat (measured by dual-energy X-ray absorptiometry) in adults in a large nationally representative US population sample from the National Health and Nutrition Examination Survey (NHANES). Design: BMI, WC, and WSR were compared with percentage body fat in a sample of 12,901 adults. Results: WC, WSR, and BMI were significantly more correlated with each other than with percentage body fat (P < 0.0001 for all sex-age groups). Percentage body fat tended to be significantly more correlated with WC than with BMI in men but significantly more correlated with BMI than with WC in women (P < 0.0001 except in the oldest age group). WSR tended to be slightly more correlated with percentage body fat than was WC. Percentile values of BMI, WC, and WSR are shown that correspond to percentiles of percentage body fat increments of 5 percentage points. More than 90% of the sample could be categorized to within one category of percentage body fat by each measure. Conclusions: BMI, WC, and WSR perform similarly as indicators of body fatness and are more closely related to each other than with percentage body fat. These variables may be an inaccurate measure of percentage body fat for an individual, but they correspond fairly well overall with percentage body fat within sex-age groups and distinguish categories of percentage body fat.

Background: Several studies have reported ethnic, education, and income differentials in concentrations of selected nutritional biomarkers in the US population. Although biomarker measurements are not subject to biased self-reports, biologic variability due to individual characteristics and behaviors related to dietary exposures contributes to within-subject variability and measurement error. Objective: We aimed to establish whether the magnitude of components of variance for nutritional biomarkers also differs in these high-risk groups. Design: We used data from 2 replicate measurements of serum concentrations of vitamins A, C, D, and E; folate; carotenoids; ferritin; and selenium in the third National Health and Nutrition Examination Survey second examination subsample (n = 948) to examine the within-subject and between-subject components of variance. We used multivariate regression methods with log-transformed analyte concentrations as outcomes to estimate the ratios of the within-subject to between-subject components of variance by categories of ethnicity, income, and education. Results: In non-Hispanic blacks, the within-subject to between-subject variance ratio for [beta]-cryptoxanthin concentration was higher (0.23; 95% CI: 0.17, 0.29) relative to non-Hispanic whites (0.13; 0.11, 0.16) and Mexican Americans (0.11; 0.07, 0.14), and the lutein + zeaxanthin ratio was higher (0.29; 0.21, 0.38) relative to Mexican Americans (0.15; 0.10, 0.19). Higher income was associated with larger within-subject to between-subject variance ratios for serum vitamin C and red blood cell folate concentrations but smaller ratios for serum vitamin A. Overall, there were few consistent up- or down-trends in the direction of covariate-adjusted variability by ethnicity, income, or education. Conclusion: Population groups at high risk of adverse nutritional profiles did not have larger variance ratios for most of the examined biomarkers.

Background: Research on the association between fruit and vegetable intake and risk of colorectal adenoma is inconclusive. Objective: We studied whether intake of fruit, vegetables, or their subgroups is associated with a lower risk of prevalent colorectal adenoma. Design: In men and women (aged 55-74 y) who were screened for colorectal cancer in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) (1993-2001), we compared 3057 cases with at least one prevalent histologically verified adenoma of the distal large bowel with 29 413 control subjects. Using a food-frequency questionnaire, we quantified intake of fruit and vegetables in the 12 mo before screening as energy-adjusted pyramid servings/d (ps/d). Adjusted odds ratios (ORs) and 95% CIs were estimated by logistic regression. Results: Risk of distal adenoma was significantly lower among subjects in high ([approximately equal to] 5.7 ps/d) versus low ([approximately equal to] 1.2 ps/d) quintiles of total fruit intake (OR: 0.75; 95% CI: 0.66, 0.86, P for trend Conclusion: Diets rich in fruit and deep-yellow vegetables, dark-green vegetables, and onions and garlic are modestly associated with reduced risk of colorectal adenoma, a precursor of colorectal cancer. KEY WORDS Fruit, vegetables, epidemiology, colorectal neoplasms, adenoma, diet

Background: The contributors to trends in increasing prevalence of obesity in the US population are poorly understood. Objective: We examined secular trends in food consumption behaviors to understand their possible contribution to increasing energy intakes and adiposity in the American population. Design: We used dietary data from 4 consecutive National Health and Nutrition Examination Surveys (NHANES) to examine trends (1971-2002) in frequency of eating episodes, meal and snack consumption, quantity of food consumed, and the energy density of foods reported by adult Americans (n = 39 094). Logistic and linear regression methods were used to adjust for multiple covariates and survey design. Results: The reported number of all eating episodes increased slightly in women from 4.90 in 1971-1975 to 5.04 in 1999-2002 (P for trend = 0.002). The amount (in g) of foods and beverages consumed, the energy density of foods, and energy intake per eating episode increased, but the mention of breakfast declined in both sexes (P for trend < 0.0001). The observed trends in mention of a snack (in men) and percentage of energy from evening food intake (in women) were downward. The amount (in g) of foods and their energy density were independent positive correlates of obesity in combined data from all surveys (P for trend < 0.0001). Conclusions: Our results do not support large increases in eating frequency, snacking, or evening eating by the American population from 1971 to 2002. The quantity of foods and their energy density increased beginning in NHANES III (1988-1994) with trajectories roughly parallel to the rates of prevalence of obesity in the US population. However, we urge cautious interpretation of these results because of concurrent changes in dietary methods during this period. KEY WORDS Secular trends, National Health and Nutrition Examination Surveys, NHANES, eating frequency, snack intake, breakfast intake, energy density, evening eating, portion size, energy intake, obesity, body mass index

Background: Dairy intake may increase prostate cancer risk, but whether this is due to calcium's suppression of circulating vitamin D remains unclear. Findings on calcium and vitamin D intake and prostate cancer are inconsistent. Objective: We examined the association of dairy, calcium, and vitamin D intake with prostate cancer. Design: In a prospective study of 3612 men followed from 1982-1984 to 1992 for the first National Health and Nutrition Examination Epidemiologic Follow-up Study, 131 prostate cancer cases were identified. Dietary intake was estimated from questionnaires completed in 1982-1984. Relative risk (RR) and 95% CIs were estimated by using Cox proportional hazards models adjusted for age, race, and other covariates. Results: Compared with men in the lowest tertile for dairy food intake, men in the highest tertile had a relative risk (RR) of 2.2 (95% CI: 1.2, 3.9; trend P = 0.05). Low-fat milk was associated with increased risk (RR = 1.5; 95% CI: 1.1,2.2; third compared with first tertile; trend P = 0.02), but whole milk was not (RR = 0.8; 95% CI: 0.5, 1.3; third compared with first tertile; trend P = 0.35). Dietary calcium was also strongly associated with increased risk (RR = 2.2; 95% CI: 1.4, 3.5; third compared with first tertile; trend P = 0.001). After adjustment for calcium intake, neither vitamin D nor phosphorus was clearly associated with risk. Conclusions: Dairy consumption may increase prostate cancer risk through a calcium-related pathway. Calcium and low-fat milk have been promoted to reduce risk of osteoporosis and colon cancer. Therefore, the mechanisms by which dairy and calcium might increase prostate cancer risk should be clarified and confirmed. KEY WORDS Dairy, diet, calcium, vitamin D, prostatic neoplasms

Background: Dietary pattern analysis is a unique approach to studying relations between diet and disease. Objective: Our objective was to describe the dietary patterns of an eastern Nebraska population and investigate the associations between those dietary patterns and risks of adenocarcinoma of the esophagus and distal stomach. Design: We recruited 124 subjects with esophageal adenocarcinoma, 124 subjects with distal stomach adenocarcinoma, and 449 control subjects in a population-based, case-control study. Results: Six dietary patterns were identified with the use of cluster analysis. The first dietary pattern represented healthy food choices and had higher energy contributions from fruit and vegetables and grain products and lower energy contributions from red meats, processed meats, and gravy than did the other dietary patterns. In contrast, a second dietary pattern was high in meats and low in fruit and cereals. The other 4 dietary patterns were each characterized by a concentrated energy source: salty snacks, desserts, milk, and white bread, respectively. The test of overall difference in cancer risk across dietary patterns was significant for distal stomach adenocarcinoma (P = 0.04) but not for esophageal adenocarcinoma. Risk of esophageal adenocarcinoma was inversely associated with intakes of dairy products, fish, all vegetables, citrus fruit and juices, and dark bread and was positively associated with gravy intake. Risk of distal stomach adenocarcinoma was positively associated with red meat intake. Conclusions: Our study suggests that a diet high in fruit and vegetables may decrease the risk of esophageal adenocarcinoma and that a diet high in meats may increase the risk of distal stomach adenocarcinoma. Am J Clin Nutr 2002;75:137-44. KEY WORDS Esophagus, stomach, neoplasm, dietary pattern, cluster analysis, cancer

Because premenopausal women experience cyclic fluctuations of plasma carotenoids and their lipoprotein carriers, it is hypothesized that carotenoid concentrations in lipoprotein fractions fluctuate by phase of the menstrual cycle. Nine women ate a standard set of carotenoid-rich foods daily for two cycles under isoenergetic conditions. In the second cycle, hormones and carotenoids in lipoprotein fractions were measured in the early and late follicular and luteal phases. ([Alpha]-Carotene concentrations in the LDL fraction were lower in the early than in the late follicular phase (P = 0.03) on the basis of regression analysis. [Beta]-carotene concentrations in the LDL fraction and the [HDL.sub.2] subfraction were higher in the late follicular than in the luteal phase (P = 0.02 and P = 0.04, respectively). Lutein/zeaxanthin concentrations in the LDL and HDL fractions were higher in the late follicular than in the luteal phase (P = 0.03 and P = 0.02, respectively). In each phase, 80% of [Alpha]-carotene, 82% of [Beta]-carotene, 85% of lycopene, and 64% of lutein/zeaxanthin were distributed in the LDL fraction. Among the hydrocarbon cartenoids, 18% of [Alpha]-carotene and of [Beta]-carotene and 13% of lycopene were distributed in the HDL fraction, with slightly more in the [HDL.sub.2] than in the [HDL.sub.3] subfraction. In contrast 34% of lutein/zeaxanthin was distributed in the HDL fraction with more concentrated in the [HDL.sub.3].than in the [HDL.sub.2] subfraction. Less than 4% of any carotenoid was found in the VLDL+IDL (intermediate-density-lipoprotein) fractions. Thus, the hydrocarbon carotenoids were highly concentrated in the LDL fraction and xanthophyll was more evenly distributed in the LDL and HDL fractions. The cyclic fluctuations of these carotenoids in lipoprotein fractions add another dimension to the understanding of their transport and physiologic function. Am J Clin Nutr 1998;67:81-7.

Relations between maternal anthropometric status during pregnancy and infant feeding practices and growth from birth through the first 6 mo of life were examined in a cohort of 351 Israeli mother-infant pairs of North African descent. Maternal weight, height, and triceps skinfold thicknesses were determined at 6 and 9 mo of pregnancy, while infants' weights and lengths were measured at birth and at 1, 2, 3, and 6 mo of age with concurrent collection of age-specific maternal-reported infant feeding data. On the basis of multiple-linear-regression analysis that adjusted for potential covariates, mean maternal weight at the first prenatal visit and at 6 and 9 mo of pregnancy were positively associated with birth length (P for trend in all cases [is less than] 0.0001) and with linear growth between birth and 1, 3, and 6 mo of age. Maternal skinfold thickness at 9 mo of pregnancy and maternal height were also significantly associated with birth length. Moreover, maternal height, weight, and skinfold thickness at 6 and 9 mo of pregnancy were positively associated with mean birth weight. After adjustment for morbidity in the past month and other covariates, infants breast-fed exclusively had greater attained weight and weight gain in the first 3 mo compared with infants who were bottle-fed exclusively, breast-fed and bottle-fed, or solid-fed exclusively. These findings underscore the need for programs that improve the nutritional status of women before, during, and after pregnancy, and encourage exclusive breast-feeding of infants for at least the first 3 mo of life.

This is the first controlled diet study to examine the fluctuation of plasma carotenoids, lipoproteins, and serum hormone concentrations by phase of the menstrual cycle. Nonsmoking, premenopausal women (n = 12) with confirmed ovulatory cycles were given a standard diet with 10 mg total carotenoids/d for two cycles under isoenergetic conditions. Blood was drawn for simultaneous measurement of carotenoids, lipoproteins, and hormones on menses days 1-2, 4-6, 11 through 1 d after the luteinizing hormone surge, and 7-8 d after the surge, representing the menses, early and late follicular, and midluteal phases, respectively. Regression modeling with adjustment for plasma cholesterol concentrations was used to compare mean individual and total plasma carotenoid concentrations by phase of the cycle. Plasma carotenoid concentrations were at their lowest at menses and significantly higher thereafter, except for [alpha]-carotene. Compared with plasma concentrations at menses, [beta]-carotene peaked (increased by 9%, P = 0.01) in the late follicular phase. Plasma lutein/zeaxanthin and anhydrolutein concentrations were higher by 8-11% (P [less than or equal to] 0.006) and by 15-31% (P [less than or equal to 0.02), respectively, during the last three phases. Plasma lycopene and phytofluene concentrations peaked (increased by 12%, P = 0.004; and by 21%, P = 0.006, respectively) at the midluteal phase. This cyclic fluctuation may affect the estimation of the plasma carotenoid-disease relation in studies of premenopausal women.

This 6-mo controlled dietary study compared the effect of 30 g alcohol/d for three menstrual cycles with three alcohol-free cycles on plasma carotenoid concentrations in 18 nonsmoking, premenopausal women. Participants were randomly allocated within a crossover design to either phase and consumed [double tilde] 6 mg total carotenoids/d under isoenergetic conditions. Blood was drawn during the third menstrual cycle of each alcohol phase. After adjustment for the mean daily specific carotenoid and energy intakes for each alcohol phase, the paired differences in mean plasma [alpha]- and [beta]-carotene concentrations were significantly higher by 19% (P = 0.027) and 13% (P = 0.034), respectively, during the alcohol-intake phase of the study. The paired difference in mean plasma lutein/zeaxanthin concentration was significantly lower by 17% (P = 0.031) when the participants consumed alcohol than when they did not. This is the first reported study in women to document the independent effect of alcohol on plasma carotenoid concentrations without the potential interaction of smoking under controlled dietary conditions.

After 10 y of urban settlement, 680 Bedouin Arab children, who had had anthropometric assessment from birth (1981-1982) through early childhood, were reassessed in 1991-1992 to compare the rates of stunting in early and later childhood as well as to describe the factors influencing current height-for-age. Stunting had dropped from 32.7% at 18 mo to 7.2% at 10 y in the 1981 birth cohort and dropped from 17.5% at 9 mo to 8.2% at 9 y in the 1982 birth cohort. Based on a multiple-linear-regression analysis, height in early childhood and maternal height were statistically significantly and positively associated with current mean height-for-age in both cohorts. In the 1982 cohort socioeconomic status in early childhood was positively and current family size was negatively and significantly associated with current mean height-for-age. Thus, conditions that were present in early childhood had the largest influence on current height. In 1992, 10% and 6% of the infant siblings of the 1981 and 1982 cohorts, respectively, were stunted compared with 17% and 1% of the siblings aged 1-2 y of the respective cohorts. Therefore, the high rates of early childhood stunting in 1981-1982 appeared to be a birth cohort-specific phenomenon. Am J Clin Nutr 1995;61; 495-500

We examined the association of percent energy intake from fat with subsequent weight change in 2580 men and 4567 women, using data from the National Health and Nutrition Examination Survey (NHANES) I Epidemiologic Follow-up Study (NHEFS). Weight change was defined as the difference between the follow-up weight (NHEFS, 1982--1984) and the baseline weight (NHANES I, 1971--1974). Fat intake was estimated from a 24-h dietary recall obtained at baseline. Regression analyses adjusted for potential confounders showed no significant association of percent fat energy with weight change in men. Among women aged

The diet-plasma relationships for carotenoids were examined in a group of 98 nonsmoking premenopausal women who participated in the cross-sectional phase of the National Cancer Institute (NCI)-US Department of Agriculture (USDA) diet study on alcohol-hormone metabolism, 1988-90. With use of the newly developed USDA-NCI carotenoid food-composition database, the mean daily intakes of carotenoids were significantly higher when estimated from the food-frequency questionnaire (FFQ) than from the 7-d diet records. Lycopene ([chi][bar] = 0.58 mmol/L), lutein plus zeaxanthin ([chi][bar] = 0.46 mmol/L), and [beta]-carotene [chi][bar] = 0.34 mmol/L) were the major plasma carotenoids. After adjustment for body mass index, energy and alcohol intakes, and total plasma cholesterol concentration, the following significant correlations (P < 0.05) were observed between the diet record and the FFQ-estimated carotenoid intakes and their respective plasma concentrations: acarotene (r = 0.58 vs 0.49), [beta]-carotene (r = 0.51 vs 0.49), [beta]-cryptoxanthin (r = 0.49 vs 0.36), lutein plus zeaxanthin (r = 0.31 vs 0.37), lycopene (r = 0.50 vs 0.26), and total carotenoids (r = 0.57 vs 0.49). These data indicate that plasma carotenoid concentrations are reflective of dietary intake, but the magnitude of the correlation varies depending on the specific carotenoid and on the dietary assessment tool. Am J Clin Nutr 1994;60:223-30.

A newly available carotenoid food-composition database providing specific carotenoid values for > 2300 foods was linked to dietary data on 57 male nonsmokers to examine the association between dietary carotenoid intake and plasma carotenoid concentrations over 3 wk when free-living. Carotenoid intake was estimated from a food-frequency questionnaire (FFQ) and 7 d of food diaries with concurrent analysis of plasma carotenoid concentrations. After adjustment for energy intake, percentage of energy from alcohol, and plasma lipid concentrations, significant diet-plasma correlations for the FFQ and the food diaries (FD) included [alpha]-carotene (r = 0.29 and 0.43), [beta]-carotene (r = 0.36 FFQ only), [beta]-cryptoxanthin (r = 0.46 and 0.44), lutein (r = 0.44 FD only), and lycopene (r =0.53 FD only). Dietary carotenoid intakes were associated with plasma carotenoid concentrations for all the carotenoids except for [beta]-carotene when food diaries were used whereas the diet-plasma correlation for the provitamin A carotenoids were consistently significant when the FFQ was used.

The objective of this study was to evaluate methods of using maternal weight and height in studies of pregnancy outcome for Hispanic women. Reference anthropometric data came from 1166 Mexican-American women in the Hispanic Health and Nutrition Examination Survey (HHANES). Prospective data on maternal anthropometry and infant birth weight came from 1362 Hispanic women in the Kaiser-Permanente Contraceptive Drug Study and 12 786 women in the Guatemalan Cooperative Perinatal Study. Five methods of standardizing weight for height were evaluated, including power-type indexes and weights relative to HHANES reference data. In linear- and logistic-regression analyses, these methods were practically interchangeable, with no evident advantage of Hispanic reference data. However, if weight was not height-standardized the. effect of height was underestimated; if height was omitted and weight was not height-standardized the effects of weight were exaggerated. Therefore, analyses of pregnancy outcome should include both height and height-standardized weight. Am J Clin Nutr 1993;58:145-51.