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Background: Measures of regional adiposity have been proposed as alternatives to the measurement of body mass index (BMI) for identifying persons at risk of future disease. Objective: The objective was to compare the magnitudes of association of BMI and alternative measurements of adiposity with coronary heart disease, diabetes, and cardiovascular disease risk factors and all-cause mortality. Design: Data from 4 cohorts of adults [3937 women from the British Women's Heart and Health Study (BWHHS); 2367 and 1950 men from phases 1 and 3, respectively, of the Caerphilly Prospective Study (CAPS); 403 men and women from the Boyd Orr Study; and 789 men and women from the Maidstone-Dewsbury Study] were analyzed. Results: The magnitudes of associations of BMI with incident coronary heart disease and cardiovascular disease risk factors were similar to those with measurements of central adiposity [waist circumference (WC), waist-hip ratio (WHR), or waist-height ratio (WHtR)] and more direct measurements of fat mass (bioimpedance/skinfold thickness). In CaPS (men only), there was no strong evidence of differences in the strengths of association with incident diabetes between BMI, WC, WHR, and WHtR (P for heterogeneity > 0.49 for all). In the BWHHS (women only), there was statistical evidence that WC [hazard ratio (HR): 2.35; 95% CI: 2.03, 2.73] and WHtR (HR: 2.29; 95% CI: 1.98, 2.66) were more strongly associated with diabetes than with BMI (HR: 1.80; 95% CI: 1.59, 2.04) (P for heterogeneity < 0.02 for both). Central adiposity measurements were positively associated with all-cause mortality, as was BMI, but only when those with a BMI (in kg/[m.sup.2]) Conclusion: No strong evidence supports replacing BMI in clinical or public health practice with other adiposity measures. Am J Clin Nutr 2010;91:547-56. doi: 10.3945/ajcn.2009.28757.

Background: Earlier studies have suggested that infant feeding may program long-term changes in cholesterol metabolism. Objective: We aimed to examine whether breastfeeding is associated with lower blood cholesterol concentrations in adulthood. Design: The study consisted of a systematic review of published observational studies relating initial infant feeding status to blood cholesterol concentrations in adulthood (ie, aged > 16 y). Data were available from 17 studies (17 498 subjects; 12 890 breastfed, 4608 formula-fed). Mean differences in total cholesterol concentrations (breastfed minus formula-fed) were pooled by using fixed-effect models. Effects of adjustment (for age at outcome, socioeconomic position, body mass index, and smoking status) and exclusion (of nonexclusive breast feeders) were examined. Results: Mean total blood cholesterol was lower (P = 0.037) among those ever breastfed than among those fed formula milk (mean difference: -0.04 mmol/L; 95% CI: -0.08, 0.00 mmol/L). The difference in cholesterol between infant feeding groups was larger (P = 0.005) and more consistent in 7 studies that analyzed 'exclusive' feeding patterns (-0.15 mmol/L; -0.23, -0.06 mmol/L) than in 10 studies that analyzed nonexclusive feeding patterns (-0.01 mmol/L; -0.06, 0.03 mmol/L). Adjustment for potential confounders including socioeconomic position, body mass index, and smoking status in adult life had minimal effect on these estimates. Conclusions: Initial breastfeeding (particularly when exclusive) may be associated with lower blood cholesterol concentrations in later life. Moves to reduce the cholesterol content of formula feeds below those of breast milk should be treated with caution.

Background: Dairy consumption affects biological pathways associated with carcinogenesis. Evidence for a link between cancer risk and dairy consumption in adulthood is increasing, but associations with childhood dairy consumption have not been studied adequately. Objective: We investigated whether dairy consumption in childhood is associated with cancer incidence and mortality in adulthood. Design: From 1937 through 1939, some 4999 children living in England and Scotland participated in a study of family food consumption, assessed from 7-d household food inventories. The National Health Service central register was used to ascertain cancer registrations and deaths between 1948 and 2005 in the 4383 traced cohort members. Per capita household intake estimates for dairy products and calcium were used as proxy for individual intake. Results: During the follow-up period, 770 cancer registrations or cancer deaths occurred. High childhood total dairy intake was associated with a near-tripling in the odds of colorectal cancer [multivariate odds ratio: 2.90 (95% CI: 1.26, 6.65); 2-sided P for trend = 0.005] compared with low intake, independent of meat, fruit, and vegetable intakes and socioeconomic indicators. Milk intake showed a similar association with colorectal cancer risk. High milk intake was weakly inversely associated with prostate cancer risk (P for trend = 0.11). Childhood dairy intake was not associated with breast and stomach cancer risk; a positive association with lung cancer risk was confounded by smoking behavior during adulthood. Conclusions: A family diet rich in dairy products during childhood is associated with a greater risk of colorectal cancer in adulthood. Confirmation of possible underlying biological mechanisms is needed. KEY WORDS Dairy products, neoplasms, life-course analysis, incidence, mortality, United Kingdom

Background: The evidence that breastfeeding protects against obesity and a variety of chronic diseases comes almost entirely from observational studies, which have a potential for bias due to confounding, selection bias, and selective publication. Objective: We assessed whether an intervention designed to promote exclusive and prolonged breastfeeding affects children's height, weight, adiposity, and blood pressure at age 6.5 y. Design: The Promotion of Breastfeeding Intervention Trial (PROBIT) is a cluster-randomized trial of a breastfeeding promotion intervention based on the WHO/UNICEF Baby-Friendly Hospital Initiative. A total of 17 046 healthy hreastfed infants were enrolled from 31 Belarussian maternity hospitals and their affiliated clinics; of those infants, 13 889 (81.5%) were followed up at 6.5 y with duplicate measurements of anthropometric variables and blood pressure. Analysis was based on intention to treat, with statistical adjustment for clustering within hospitals or clinics to permit inferences at the individual level. Results: The experimental intervention led to a much greater prevalence of exclusive breastfeeding at 3 mo in the experimental than in the control group (43.3% and 6.4%, respectively; P < 0.001) and a higher prevalence of any breastfeeding throughout infancy. No significant intervention effects were observed on height, body mass index, waist or hip circumference, triceps or subscapular skinfold thickness, or systolic or diastolic blood pressure. Conclusions: The breastfeeding promotion intervention resulted in substantial increases in the duration and exclusivity ofbreastfeeding, yet it did not reduce the measures of adiposity, increase stature, or reduce blood pressure at age 6.5 y in the experimental group. Previously reported beneficial effects on these outcomes may be the result of uncontrolled confounding and selection bias. KEY WORDS Breastfeeding, adiposity, obesity, blood pressure, programming

Background: Previous studies reported inconsistent associations between breastfeeding and body mass index (BML in kg/[m.sup.2]). Associations with body fatness are unknown. Objective: We investigated the association of breastfeeding with fatness measured by dual-energy X-ray absorptiometry. Design: The prospective cohort study involved 4325 singletons with measurements at 9-10 y of age to assess the main outcomes of BMI and total and trunk fat masses. Results: Prevalence of any breastfeeding was 82%. In crude analyses. breastfeeding was inversely associated with total fat mass [% change per category increase (4 categories)] in breastfeeding duration (-4.4%; 95% CI: -3.1%, -5.6%) and trunk fat mass (-0.5%: 95% CI: - 1.1%, 0.1%); the odds of adiposity were measured by total [odds ratio (OR): 0.81 ; 95% CI: 0.75, 0.88] and trunk (OR: 0.78; 95% CI: 0.71,0.84) fat masses in the top decile. In adjusted models, the inverse association of breastfeeding with mean total fat mass was attenuated by 59% (% change per category increase in breastfeeding duration: -1.8%: 95% CI: -0.5%, -3.1%), but associations with trunk fat mass (% change per category increase in breastfeeding duration: -0.6%; 95% CI: 0.0%, -1.3%) and the ORs for total (0.76; 95% CI: 0.69, 0.84) and trunk (0.74; 95% CI: 0.67, 0.81) fat masses in the top decile were little altered. Children breastfed [greater than or equal to] 6 mo had the lowest odds of total fat mass in the top decile (OR: 0.45; 95% CI: 0.33, 0.62). In multivariate models, there was little evidence that breastfeeding was associated with mean or threshold values of BMI. Conclusions: The protective association of breastfeeding with mean total fat mass was attenuated somewhat after adjustment for con-founders, which indicated that confounding may explain this association. Breastfeeding may protect against obesity if maintained for [greater than or equal to] 6 too. KEY WORDS Avon Longitudinal Study of Parents and Children, ALSPAC, epidemiology, diet, prevention and control, energy metabolism, feeding behavior

Background: Observational evidence suggests that having been breastfed in infancy may reduce the prevalence of type 2 diabetes in later life. Objective: The objective was to examine the influence of initial breastfeeding on type 2 diabetes and blood glucose and insulin concentrations. Design: A systematic review of published studies identified 1010 reports; 23 examined the relation between infant feeding and type 2 diabetes in later life or risk factors for diabetes. Risk factors in infants were examined separately from those in children and adults. All estimates were pooled by using fixed-effect models; differences Results: Subjects who were breastfed had a lower risk of type 2 diabetes in later life than did those who were formula fed (7 studies; 76 744 subjects; odds ratio: 0.61; 95% CI: 0.44, 0.85; P = 0.003). Children and adults without diabetes who had been breastfed had marginally lower fasting insulin concentrations than did those who were formula fed (6 studies; 4800 subjects; percentage difference: -3%; 95% CI: -8%, 1%; P = 0.13); no significant difference in fasting glucose concentrations was observed. Breastfed infants had lower mean preprandial blood glucose (12 studies; 560 subjects; mean difference: -0.17 mmol/L; 95% CI: -0.28, -0.05 mmol/L; P = 0.005) and insulin (7 studies; 291 subjects; mean difference: -2.86 pmol/L; 95% CI: -5.76, 0.04 pmol/L; P = 0.054) concentrations than did those who were formula fed. Conclusion: Breastfeeding in infancy is associated with a reduced risk of type 2 diabetes, with marginally lower insulin concentrations in later life, and with lower blood glucose and serum insulin concentrations in infancy. KEY WORDS Infant feeding, blood glucose, serum insulin, type 2 diabetes, systematic review

Background: It is unclear whether early life body mass index (BMI; in kg/[m.sup.2]) is associated with adult cardiovascular disease. Objective: The objective was to assess the association of early life BMI with the risk of ischemic heart disease (IHD) and stroke. Design: The association between early life BMI and risk of adult mortality from IHD and stroke was assessed in 3 historical cohort studies in which height and weight had been assessed by using standard procedures. Participants were traced and linked to national mortality data. Participants in the 3 cohorts were born between 1922 and 1937, 1927 and 1956, and 1928 and 1950 and were aged 2-15, 9-18, and 16-22 y, respectively, at the time of assessment of their height and weight. Results: Participants in all 3 cohorts had mean BMIs similar to those reported for contemporary children and young adults, but fewer of the cohort participants were overweight or obese. BMI was not associated with future risk of IHD or stroke in any cohort. The pooled (all 3 cohorts) adjusted hazard ratio per SD of early life BMI was 1.09 (95% CI: 1.01, 1.19) for IHD and 0.94 (95% CI: 0.82, 1.08) for stroke. The pooled hazard ratio of IHD when participants who were overweight or obese for their age were compared with all other participants was 1.34 (95% CI: 0.95, 1.91), and no association was found between overweight or obesity and stroke risk. The effects of BMI did not vary by cohort or by age. Conclusion: These results do not provide strong evidence that being overweight or obese in childhood is associated with future cardiovascular disease risk. KEY WORDS Body mass index, childhood, cardiovascular disease, life-course epidemiology

Background: Evidence from observational studies has suggested that breastfeeding may reduce the prevalence of obesity in later life. Objective: The objective was to examine whether initial breastfeeding is related to lower mean body mass index (BMI: in kg/[m.sup.2]) throughout life. Design: The study was a systematic review of published studies investigating the association between infant feeding and a measure of obesity or adiposity in later life, which was supplemented with data from unpublished sources. Analyses were based on the mean differences in BMI between those subjects who were initially breastfed and those who were formula-fed (expressed as breastfed minus bottle-fed), which were pooled by using fixed-effects models throughout. Results: From 70 eligible studies, 36 mean differences in BMI (from 355 301 subjects) between those breastfed and those formula-fed (reported as exclusive feeding in 20 studies) were obtained. Breast-feeding was associated with a slightly lower mean BMI than was formula feeding (-0.04; 95% CI: -0.05, -0.02). The mean difference in BMIs appeared larger in 15 small studies of < 1000 subjects (-0.19; 95% CI: -0.31, -0.08) and smaller in larger studies of [micro] 1000 subjects (-0.03; 95% CI: -0.05, -0.02). An Egger test was statistically significant (P = 0.002). Adjustment for socioeconomic status, maternal smoking in pregnancy, and maternal BMI in 11 studies abolished the effect (-0.10: 95% CI: -0.14, -0.06 before adjustment; -0.01: 95% CI: -0.05, 0.03 after adjustment). Conclusions: Mean BMI is lower among breastfed subjects. However, the difference is small and is likely to be strongly influenced by publication bias and confounding factors. Promotion of breastfeeding, although important for other reasons, is not likely to reduce mean BMI. KEY WORDS: Infant feeding, body mass index, systematic review

Background: Evidence suggests that environmental factors acting early in life may affect blood pressure in adulthood. Objective: The objective was to test the hypothesis that dried formula milk (derived from cow milk) intake in infancy is positively associated with blood pressure in early adulthood. Design: We conducted a long-term follow-up (1997-1999) of the Barry Caerphilly Growth study cohort (1972-1974) into which mothers and their offspring had originally been randomly assigned to receive a milk supplement or usual care. Participants were the offspring, who were aged 23-27 y at follow-up. The main outcome measures were systolic and diastolic blood pressure. Results: The social and demographic characteristics of the subjects who were (n = 679) and were not (n = 272) followed up were similar. For each increase in quartile of dried milk consumption (in oz) at 3 mo of age, there was a 1.28-mm Hg (95% CI: 0.46, 2.10 mm Hg) increase in systolic and a 0.63-mm Hg (95% CI: 0.04, 1.22 mm Hg) increase in diastolic blood pressure after adjustment for sex, intervention group, birth weight z scores, social class in childhood, age at follow-up, alcohol consumption, and pack-years of smoking. These coefficients were attenuated when adult body mass index and height were included in the models, but the association of dried milk consumption at 3 mo of age with systolic pressure remained significant (1.07 mm Hg; 95% CI: 0.27, 1.87 mm Hg). Conclusions: Our findings are consistent with the hypothesis that high blood pressure in later life is influenced by early postnatal nutrition. Thus, interventions to optimize infant nutrition may have important long-term health benefits. KEY WORDS Infant nutrition, formula feeding, blood pressure, hypertension, cardiovascular disease, cohort studies