Eggs and a Fiber-Rich Diet Are Beneficially Associated with Lipid Levels in Framingham Offspring Study Adults

Background

For many years, United States' dietary policy recommended limiting egg intake to no more than 3/wk in the belief that restricting dietary cholesterol would lower plasma cholesterol levels and thereby reduce the risk of cardiovascular disease. The evidence supporting these recommendations is controversial.

Objectives

To examine the impact of eggs, a major contributor to dietary cholesterol intake, on lipid levels and to determine whether these egg effects are modified by other healthy dietary factors in adults.

Methods

Males and females aged 30-64 y with available 3-d diet record data, without cardiovascular disease and not taking lipid- or glucose-lowering medications in the prospective Framingham Offspring cohort were included (n = 1852). Analysis of covariance models were used to compare mean follow-up lipid levels adjusting for age, sex, BMI, and dietary factors. Cox proportional hazard's models were used to estimate risk for elevated lipid levels.

Results

Consuming ≥5 eggs/wk was not adversely associated with lipid outcomes. Among men, consuming ≥5 (compared with <0.5) eggs/wk was associated with an 8.6 mg/dL lower total cholesterol level and a 5.9 mg/dL lower LDL cholesterol level, as well as lower triglycerides. Overall, higher egg intake combined with higher dietary fiber (compared with lower intakes of both) was associated with the lowest total cholesterol, LDL cholesterol, and LDL cholesterol-to-HDL cholesterol ratio. Finally, diets with higher (compared with lower) egg intakes in combination with higher total fish or fiber intakes, respectively, were associated with lower risks of developing elevated (>160 mg/dL) LDL cholesterol levels (hazard ratio: 0.61; 95% confidence interval: 0.44, 0.84; and HR: 0.70; 95% confidence interval: 0.49, 0.98, respectively).

Conclusions

Higher egg intakes were beneficially associated with serum lipids among healthy adults, particularly those who consumed more fish and dietary fiber.

Animal protein intake reduces risk of functional impairment and strength loss in older adults

BACKGROUND & AIMS

Protein intake has been shown to lower risk of aging-related functional decline. The goal of this study was to assess long-term effects of weight-adjusted animal (AP) and plant protein (PP) intakes on aging-related change in functional status and grip strength.

METHODS

Framingham Offspring Study participants (n = 1896, 891 men and 1005 women), ≥age 50, were followed for an average of 14.4 years. Protein intake derived from two sets of 3-day diet records (exams 3 and 5) was expressed as both weight-adjusted intake (from residuals) and per kilogram of body weight (g/kg/d). Seven tasks from two standardized assessments (Nagi and the Rosow-Breslau scales) were selected to determine functional status at exams 5-9. Functional impairment was defined as failure to complete (or having a lot of difficulty completing) a given task. Grip strength was assessed by dynamometer at exams 7-9.

RESULTS

Participants with higher (vs. lower) weight-adjusted intakes of AP and PP maintained higher functional scores (p = 0.001 and p < 0.001, respectively). After accounting for baseline skeletal muscle mass (SMM) and physical activity, only AP was linked with lower risks of functional impairment. Higher AP intake among sedentary individuals led to 29% (95% CI: 0.51-1.00) reduced risks of impairment; among subjects with lower SMM, higher AP was associated with 30% (95% CI: 0.49-0.98) reduced risks. Physical activity and SMM were independently associated with reduced risks of functional impairment, regardless of protein intake. Finally, higher AP intake led to 34% and 48% greater preservation of grip strength in men (p = 0.012) and women (p = 0.034). Results were similar for protein intake expressed as g/kg/d.

CONCLUSIONS

Higher AP intake and higher levels of physical activity and SMM were independently associated with lower risks of functional impairment and greater preservation of grip strength in adults over the age of 50 years.

Dietary Sodium, Potassium, Magnesium, and Calcium: Effects on Risks of Incident Cardiovascular Disease in the Framingham Offspring Study

Objectives

The objectives of this study were to determine the dose-response relations and combined effects of sodium, potassium, magnesium and calcium on the risk of cardiovascular disease.

Methods

Data for 2362 30–64 year-old men and women free of CVD at baseline in the Framingham Offspring Study were included in these analyses. Cox proportional hazard models were used to investigate the association between categories of sodium, potassium, calcium, and magnesium intake and risk of incident CVD. Further, Cox models with restricted cubic spline functions were used to examine the dose-response relations of these minerals with CVD risk.

Results

Compared with higher sodium intakes (≥3500 mg), those with the lowest intakes (&lt;2500 mg/d) had no statistically significant reduction in risk of CVD. In contrast, potassium intake ≥3000 (vs. &lt;2500) mg/day was associated with a 25% lower risk (95% CI: 0.59–0.95) of CVD; magnesium intake ≥320 (vs. &lt;240) mg/day led to a 34% lower risk (95% 0.51–0.87). Restricted cubic spline curves showed inverse dose-response relationships for both potassium and magnesium with CVD risk but no association with either sodium or calcium. Higher intakes of both potassium and magnesium were beneficially associated with CVD risk even among those with sodium intakes ≥2500 mg/day.

Conclusions

Sodium intake was not associated with CVD risk within the range of intakes generally consumed by these participants. In contrast, higher intakes of both potassium and magnesium were inversely associated with risk of CVD.

Funding Sources

Funding for this work was provided by the National Heart Lung and Blood Institute and National Dairy Council.

Anthropometric measures of body fat and obesity-related cancer risk: sex-specific differences in Framingham Offspring Study adults

BACKGROUND/OBJECTIVE

Obesity has been associated with the risk of developing certain cancers. A limited number of studies have examined effects of various anthropometric measures of body composition on cancer risk. The aim of this study was to estimate the sex-specific effects of various anthropometric measures on risk of obesity-related cancers (ObCa).

SUBJECTS/METHODS

Data on body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHtR), and hip circumference (HC) among 3818 45-69-year olds in the Framingham Offspring Study were included. Cox proportional hazards models were used to estimate adjusted risks of 16 obesity-related cancers, with the most common being postmenopausal breast, endometrial, and colon cancers.

RESULTS

Obesity as measured by BMI in both men and women was a predictor of ObCa; those in the highest quintile (Q5) of BMI (>30.07 in women; >30.80 kg/m² in men) had more than twice the risk of ObCa (HR = 2.07; 95% CI: 1.06-4.07 (women) and HR = 2.25; 95% CI: 1.08-4.69 (men)). Waist-related measures (WC, WHtR) were stronger predictors of ObCa in men than in women, and HC confounded the relations between waist size and cancer risk. After adjusting for HC, men in Q5 of WC had more than a threefold increased risk of ObCa (HR: = 3.22; 95% CI: 1.39-7.45). Comparable effects in women were weak and non-statistically significant. Results were similar for WHtR. Finally, an inverse J-shaped relation was found between HC and ObCa after adjusting for WC among men but not in women.

CONCLUSIONS

These results suggest that obesity as measured by BMI is a predictor of obesity-related cancer risk in men and women. They also suggest that waist and hip circumference measures are interrelated and confound the independent effects of each measure. Among men, a large waist size and a small hip size are independent predictors of cancer risk.

Long-term yogurt consumption and risk of incident hypertension in adults

OBJECTIVE

To evaluate the relation between yogurt consumption as well as cheese, milk, and total dairy, and high blood pressure (HBP) in two Nurses' Health Study cohorts (NHS, n = 69 298), NHS II (n = 84 368) and the Health Professionals Follow-Up Study (HPFS, n = 30 512).

METHODS

NHS, NHS II, and HPFS participants were followed for incident HBP for up to 30, 20, and 24 years, respectively. Hazard ratios were calculated using time-dependent multivariate-adjusted Cox proportional hazards models. Pooled risk estimates were derived from fixed effects meta-analyses.

RESULTS

Participants consuming at least five servings per week (vs. <1 serving per month) of yogurt in NHS, NHS II, and HPFS had 19% (95% CI 0.75-0.87), 17% (95% CI 0.77-0.90), and 6% (95% CI 0.83-1.07) lower HBP risks, respectively. In pooled analyses of these cohorts, higher yogurt consumption was linked with 16% (95% CI 0.80-0.88) lower HBP risk; higher total dairy (3 to <6 vs. <0.5 servings/day), milk (2 to <6/day vs. <4/week) and cheese (1 to 4/day vs. <1/week) were associated with 16% (95% CI 0.81-0.87), 12% (95% CI 0.86-0.90), and 6% (95% CI 0.90-0.97) lower HBP risks, respectively. After controlling for BMI as a possible causal intermediate, total dairy, yogurt, milk, and cheese were associated with 13, 10, 8, and 8% lower HBP risks, respectively. The combination of higher yogurt intake and higher DASH ('Dietary Approaches to Stop Hypertension') diet scores was associated with 30% (95% CI 0.66-0.75) lower HBP risk compared with lower levels of both factors.

CONCLUSION

Higher total dairy intake, especially in the form of yogurt, was associated with lower risk of incident HBP in middle-aged and older adult men and women.

Dietary Protein and Preservation of Physical Functioning Among Middle-Aged and Older Adults in the Framingham Offspring Study

Dietary protein may help prevent age-related declines in strength and functional capacity. This study examines the independent relationship between dietary protein and longitudinal changes in physical functioning among adults participating in the Framingham Offspring Study from examination 5 (1991–1995) to examination 8 (2005–2008). Protein intakes were derived from 3-day diet records during examinations 3 and 5; functional status was determined over 12 years using 7 items selected from standardized questionnaires. Multivariable models adjusted for age, sex, education, physical activity, smoking, height, and energy intake. Functional tasks that benefitted most from a higher-protein diet (≥1.2 g/kg/day vs. <0.8 g/kg/day) were doing heavy work at home, walking 1/2 mile (0.8 km), going up and down stairs, stooping/kneeling/crouching, and lifting heavy items. Those with higher protein intakes were 41% less likely (95% CI: 0.43, 0.82) to become dependent in 1 or more of the functional tasks over follow-up. Higher physical activity and lower body mass index were both independently associated with less functional decline. The greatest risk reductions were found among those with higher protein intakes combined with either higher physical activity, more skeletal muscle mass, or lower body mass index. This study demonstrates that dietary protein intakes above the current US Recommended Daily Allowance may slow functional decline in older adults.

Dietary Cholesterol Intake Is Not Associated with Risk of Type 2 Diabetes in the Framingham Offspring Study

Identification of diet and lifestyle risk factors for prevention of type 2 diabetes mellitus (T2DM) is of great importance. The specific role of dietary cholesterol (DC) in T2DM risk is unclear. This study uses data from 2192 Framingham Offspring Study subjects to estimate the effects of DC alone and in combination with markers of a healthy diet and other lifestyle factors on fasting glucose and risk of T2DM or impaired fasting glucose (IFG) over 20 years of follow-up. Dietary data were derived from two sets of three-day food records. Statistical methods included mixed linear regression and Cox proportional hazard's modeling to adjust for confounding. There were no statistically significant differences in glucose levels over 20 years of follow-up across DC intake categories (.

Regular Yogurt Intake and Risk of Cardiovascular Disease Among Hypertensive Adults

BACKGROUND

High blood pressure (HBP) is a major cardiovascular disease (CVD) risk factor. Clinical trials including Dietary Approaches to Stop Hypertension (DASH) have demonstrated beneficial effects of dairy consumption on risks of HBP and CVD. Yogurt, a fermented dairy product, may independently be related to CVD risk.

OBJECTIVE

To evaluate the association between yogurt consumption and CVD risk among hypertensive individuals in 2 large cohorts and to determine whether the association differs among those whose eating pattern more closely resembles the DASH diet.

METHODS

Overall, 55,898 female Nurses' Health Study (NHS) and 18,232 male Health Professionals Follow-Up Study (HPFS) participants with prevalent HBP were included. Cumulative average estimates of yogurt intake from validated food frequency questionnaires were related to verified self-reported CVD outcomes using Cox proportional hazards models. Hazard ratios and 95% confidence intervals (CI) were adjusted for CVD risk factors, medications, and diet covariates.

RESULTS

Yogurt intake was inversely associated with CVD risk (myocardial infarction and stroke) among hypertensive participants (P <0.01 in both cohorts). Among participants consuming ≥2 servings/week of yogurt, NHS women had a 17% (95% CI: 0.74-0.92) lower risk while HPFS men experienced a 21% (95% CI: 0.66-0.96) lower CVD risk compared to those who consumed <1 serving/month. Regular yogurt consumers with higher DASH diet scores had 16% (95% CI: 0.73-0.96) and 30% (95% CI: 0.57-0.85) CVD risk reductions in the 2 cohorts, respectively.

CONCLUSION

Hypertensive men and women who consumed ≥2 servings/week of yogurt, especially in the context of a healthy diet, were at lower risk for developing CVD.

High-Protein Foods and Physical Activity Protect Against Age-Related Muscle Loss and Functional Decline

Background

Some clinical trials suggest that protein supplementation enhances the effects of resistance exercise on skeletal muscle mass (SMM); fewer studies examine the effects of diets rich in protein-source foods on SMM and functional status among community-dwelling adults.

Methods

Data from the Framingham Offspring study including diet (three-day records, exams 3 and 5), physical activity (exams 2 and 4), percent SMM (%SMM) (exams 6 and 7), and functional performance (exams 5 through 8) were used to evaluate independent and combined effects of physical activity and high-protein foods on adjusted mean %SMM (using analysis of covariance) and risk of functional decline (using Cox proportional hazard's models). Analyses were adjusted for such factors as age, education, height, smoking, and fruit and grain consumption).

Results

Higher intakes of protein-source foods (red meat, poultry, fish, dairy, and soy, nuts, seeds and legumes) were associated with higher %SMM over 9 years, particularly among women. Men and women with higher intakes of foods from animal sources had a higher % SMM regardless of activity; beneficial effects of plant-based protein foods were only evident in physically active adults. Active subjects with higher intakes of animal or plant protein-source foods had 35% lowest risks of functional decline. Among less active individuals, only those consuming more animal protein-source foods had reduced risks of functional decline (HR: 0.7l; 95% CI: 0.50-1.01).

Conclusion

Higher intake of animal-protein foods, alone and especially in combination with a physically active lifestyle, was associated with preservation of muscle mass and functional performance in older adults.

Longitudinal effects of dietary sodium and potassium on blood pressure in adolescent girls

IMPORTANCE

Identification of risk factors early in life for the development of high blood pressure is critical to the prevention of cardiovascular disease.

OBJECTIVE

To study prospectively the effect of dietary sodium, potassium, and the potassium to sodium ratio on adolescent blood pressure.

DESIGN, SETTING, AND PARTICIPANTS

The National Heart, Lung, and Blood Institute's Growth and Health Study is a prospective cohort study with sites in Richmond, California; Cincinnati, Ohio; and Washington, DC. Participants included 2185 black and white girls initially aged 9 to 10 years with complete data for early-adolescent to midadolescent diet and blood pressure who were followed up for 10 years. The first examination visits were from March 1987 through February 1988 and follow-up continued until February 1999. Longitudinal mixed models and analysis of covariance models were used to assess the effect of dietary sodium, potassium, and the potassium to sodium ratio on systolic and diastolic blood pressures throughout adolescence and after 10 years of follow-up, adjusting for race, height, activity, television/video time, energy intake, and other dietary factors.

EXPOSURES

Mean dietary sodium and potassium intakes and the mean potassium to sodium ratio in individuals aged 9 to 17 years. To eliminate potential confounding by energy intake, energy-adjusted sodium and potassium residuals were estimated.

MAIN OUTCOMES AND MEASURES

Mean systolic and diastolic blood pressures throughout adolescence and at the end of follow-up (individuals aged 17-21 years).

RESULTS

Sodium intakes were classified as less than 2500 mg/d (19.4% of participants), 2500 mg/d to less than 3000 mg/d (29.5%), 3000 mg/d to less than 4000 mg/d (41.4%), and 4000 mg/d or more (9.7%). Potassium intakes ranged from less than 1800 mg/d (36.0% of participants) to 1800 mg/d to less than 2100 mg/d (26.2%), 2100 mg/d to less than 2400 mg/d (18.8%), and 2400 mg/d or more (19.0%). There was no evidence that higher sodium intakes (3000 to <4000 mg/d and ≥4000 mg/d vs <2500 mg/d) had an adverse effect on adolescent blood pressure and longitudinal mixed models showed that those consuming 3500 mg/d or more had generally lower diastolic blood pressures compared with individuals consuming less than 2500 mg/d (P = .18). However, higher potassium intakes were inversely associated with blood pressure change throughout adolescence (P < .001 for systolic and diastolic) and at the end of follow-up (P = .02 and P = .05 for systolic and diastolic, respectively). While the potassium to sodium ratio was also inversely associated with systolic blood pressure (P = .04), these effects were generally weaker compared with effects for potassium alone.

CONCLUSIONS AND RELEVANCE

In this study of adolescent girls, consumption of 3500 mg/d of sodium or more had no adverse effect on blood pressure. The beneficial effects of dietary potassium on both systolic and diastolic blood pressures suggest that consuming more potassium-rich foods during childhood may help suppress the adolescent increase in blood pressure.

Diets higher in protein predict lower high blood pressure risk in Framingham Offspring Study adults

BACKGROUND

Short-term clinical trials suggest that dietary protein lowers blood pressure (BP); however, long-term effects of total, animal, and plant proteins are less clear. Our goal was to evaluate effects of these dietary proteins on mean systolic BP (SBP) and diastolic BP (DBP) and incident high BP (HBP) risk among middle-aged adults in the Framingham Offspring Study.

METHODS

Men and women (aged 30-54 years) without prevalent HBP, cardiovascular disease, or diabetes with 3-day dietary records from exams 3 or 5 (n = 1,361) were included and followed for a mean of 11.3 years for development of HBP. Protein intakes adjusted for body size were derived using the residual method. Analysis of covariance and Cox proportional hazard's models were used to adjust for age, sex, education, height, activity, smoking, fat calories, diet quality, and body mass index.

RESULTS

Higher protein intakes were associated with lower mean SBP and DBP. Both animal and plant proteins lowered BP and led to statistically significant reductions in HBP risk (hazard ratios of 0.68 and 0.51, respectively). Participants in the highest tertile of total protein intake had 40% less risk (95% confidence interval [CI], 0.45-0.78) of developing HBP. Beneficial effects of protein were apparent for men and women and for normal-weight and overweight individuals. Higher protein diets also characterized by higher fiber intakes led to a 59% reduction (95% CI, 0.37-0.66) in HBP risk.

CONCLUSIONS

Adults consuming more dietary protein from either plant or animal sources had lower long-term risks of HBP.

Adolescent dietary intakes predict cardiometabolic risk clustering

PURPOSE

To prospectively examine the relation between adolescent dietary intake and cardiometabolic risk (CMR) clustering at the end of adolescence.

METHODS

Data from the NHLBI Growth and Health Study on 1369 girls enrolled at ages 9-10 in 1987-1988 and followed for 10 years were used to estimate the relative risk of having multiple (≥2 or ≥3) risk factors in late adolescence associated with usual food intake patterns from 9 to 17 years of age. Mean food intakes were derived from multiple 3-day diet records and CMR factors included larger waist circumference, insulin resistance, low high-density lipoprotein cholesterol, high low-density lipoprotein cholesterol, high triglycerides, and elevated systolic or diastolic blood pressures.

RESULTS

Of 1369 subjects, 18.4 % girls had 3-6 prevalent risk factors by the end of adolescence and 35.0 % had at least two. Higher intakes of fruit and non-starchy vegetables, dairy, and grains were independently associated with having fewer risk factors as were eating patterns characterized by higher combined intakes of these food groups. After adjusting for age, race, socio-economic status, height, physical activity, and television watching, girls with high intakes of dairy and fruits and non-starchy vegetables (vs. those with lower intakes of both) were nearly 50 % less likely to have three or more CMR factors in late adolescence; girls with higher intakes of grains plus fruits and non-starchy vegetables were nearly 60 % less likely.

CONCLUSION

These results suggest that healthy food consumption patterns during adolescence may prevent accumulation of cardiometabolic risk.

Beverage intake in early childhood and change in body fat from preschool to adolescence

BACKGROUND

Childhood obesity is closely associated with adult obesity, hypertension, and cardiovascular disease. This study's aim was to determine the effects of beverage intake patterns on body composition from early childhood into adolescence in the Framingham Children's Study.

METHODS

Multiple sets of 3-day records were used to assess diet over 12 years, beginning in 1987, in 103 non-Hispanic white boys and girls. BMI, waist circumference, and four skinfolds (triceps, subscapular, suprailiac, and abdominal) were measured yearly. Percent body fat was assessed by dual-energy X-ray absorptiometry at end of follow-up. Analysis of covariance and longitudinal mixed modeling were used to control for potential confounding by age, baseline body fat, percent of energy from fat, television/video viewing time, other beverage intakes not included in exposure group, mother's education, and BMI.

RESULTS

Children with the lowest milk intakes in early childhood had 7.4% more body fat in later adolescence than those with higher intakes (30.0% body fat in tertile 1 vs. 22.6% in tertile 3; p=0.0095). Fruit and vegetable juice was similarly protective-those in the highest tertile of fruit and vegetable juice intake during childhood had an 8.0-cm smaller waist circumference at 15-17 years of age, compared with those in the lowest tertile (p=0.0328). There was no relation between sugar-sweetened beverages (SSBs) and percent body fat (p=0.9296) or other outcomes.

CONCLUSIONS

These results suggest that adequate intakes of milk and fruit and vegetable juice may reduce the risk of excess body fat in later childhood and adolescence. Further, modest intakes of SSBs in early childhood may not adversely affect body fat change.

Lean red meat consumption and lipid profiles in adolescent girls

BACKGROUND

Epidemiological studies of red meat consumption often fail to distinguish between leaner and fattier or processed cuts of meat. Red meat has also been frequently linked with less healthy diet patterns. Data exploring the health effects of lean red meat in younger individuals are scarce, particularly in the context of a healthy diet. The present study examined the effects of lean red meat in combination with higher intakes of fruit/nonstarchy vegetables on lipid profiles in older adolescent girls.

METHODS

Data from 1461 girls who were followed for 10 years, starting at 9-10 years of age, in the National Heart Lung and Blood Institute Growth and Health Study were used. Diet was assessed using multiple sets of 3-day records collected over eight examination cycles. Outcome measures included fasting levels of low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), non-HDL-C and triglycerides at age 18-20 years.

RESULTS

After adjusting for age, race, socioeconomic status, height, activity level, hours of television per day, and intakes of whole grains and dairy foods using multivariable modelling, girls consuming ≥6 oz lean red meat per week combined with two or more servings of fruit/nonstarchy vegetables per day had LDL-C levels approximately 6-7 mg dL(-1) lower (P < 0.05) than girls with lower intakes of lean red meat and fruit/nonstarchy vegetables. In addition, girls with higher intakes of both were 33% less likely (odds ratio = 0.67, 95% confidence interval = 0.48-0.94) to have an LDL-C ≥110 mg dL(-1) and 41% less likely (odds ratio = 0.59, 95% confidence interval = 0.42-0.83) to have an elevated LDL : HDL ratio (≥2.2) at the end of adolescence.

CONCLUSIONS

These analyses suggest that lean red meat may be included in a healthy adolescent diet without unfavourable effects on lipid values.

Eating patterns and lipid levels in older adolescent girls

BACKGROUND AND AIMS

Few studies have evaluated the effects of food-based eating patterns on adolescent lipid levels. This study examines whether usual adolescent eating patterns (ages 9-17 years) predict lipid levels at 18-20 years of age.

METHODS AND RESULTS

This study uses previously collected data from the longitudinal NHLBI Growth and Health Study in which 2379 girls were enrolled at ages 9-10 years and followed for ten years. Food-based eating patterns were derived from multiple 3-day diet records. After adjusting for age, race, socioeconomic status, height, physical activity, and television viewing, girls with higher intakes of dairy, fruit and non-starchy vegetables had about a 40-50% reduced risk an LDL-C ≥ 170 mg/dL and non-HDL-C ≥ 145 mg/dL. Diets characterized by higher intakes of dairy and whole grains had similar benefits on TC and LDL-C. Girls consuming more fruits and non-starchy vegetables as well as more whole grains were much less likely to have high-risk lipid levels. Lean meat, poultry and fish when consumed in the context of other healthy eating patterns had no adverse effects on lipid levels in late adolescence. In fact when consumed with higher amounts of fruit and non-starchy vegetables, lean meat, poultry and fish had beneficial effects on HDL. Finally, dietary patterns that included more whole grains tended to be associated with lower TG levels.

CONCLUSION

Healthy childhood eating patterns characterized by higher intakes of a variety of fruits, vegetables, whole grains, dairy, lean meat, poultry and fish are important modifiable predictors of lipid levels in late adolescence.

Dairy intake and anthropometric measures of body fat among children and adolescents in NHANES

OBJECTIVE

To explore the relation between dairy intake and body fat among children and adolescents.

MATERIALS AND METHODS

Children (5-11 years) and adolescents (12-16 years) were included who had data on diet, anthropometry measures of body fat, and relevant potential confounders (children: n = 3,864 and 2,231; adolescents: n = 1,884 and 2,636 in NHANES III and NHANES 1999-2002, respectively). Each child's daily dairy intake from 24-hour recalls was classified as low, moderate or high. For girls and boys, respectively: low intake: <1 and <2 servings; moderate intake: 1-<3 and 2-<4 servings; and high intake: >or=3 and >or=4 servings per day.) Analysis of covariance was used to control for potential confounding by age, gender, socio-economic status, race/ethnicity, height and television watching.

RESULTS

Among children, there was no consistent association between dairy intake and anthropometric indices of body fat. Among adolescents, the lowest dairy intake group (< one serving per day for girls and < two per day for boys) had higher estimated levels of body fat than those in the highest dairy group. Compared with the lowest intake level, adolescent girls in NHANES III who consumed 1-<3 servings per day of dairy had about 2.5 mm less subcutaneous body fat (95% CI: -4.70 mm, -0.39 mm) while girls consuming three or more servings had about 5 mm less fat in their sum of two skinfolds. Adolescent boys consuming 4 or more servings of dairy per day had lower anthropometry levels than did those consuming less than two servings.

CONCLUSION

Among adolescents, suboptimal dairy intake was associated with higher anthropometric measures of body fat.

Effects of average childhood dairy intake on adolescent bone health

OBJECTIVE

To evaluate the effects of usual childhood dairy intake on adolescent bone health.

STUDY DESIGN

Dietary data collected in the Framingham Children's Study over 12 years were used to evaluate usual dairy consumption and adolescent bone health. Each child's average Food Pyramid servings were estimated from yearly sets of 3-day diet records. Bone mineral content (BMC) and area (BA) for total body and 6 regions (arms, legs, trunk, ribs, pelvis, and spine) at ages 15 to 17 years were the primary outcomes. Analysis of covariance was used to adjust for potential confounding by sex and physical activity, as well as age, height, body mass index and percent body fat at the time of the bone scan.

RESULTS

Consuming >or= 2 servings/day of dairy (versus less) was associated with significantly higher mean BMC and BA. Higher intakes of meats/other proteins (>or= 4 servings per/day) were also associated with higher mean BMC and BA values. Children with higher intakes of both dairy and meats/other proteins had the highest adjusted BMC (3090.1 g), and children consuming less of each had the lowest BMC (2740.2 g).

CONCLUSIONS

These prospective data provide evidence for a beneficial effect of childhood dairy consumption on adolescent bone health.

Low dairy intake in early childhood predicts excess body fat gain

OBJECTIVE

To estimate the effect of dairy intake in early childhood on the acquisition of body fat throughout childhood.

RESEARCH METHODS AND PROCEDURES

Ninety-nine of the original 106 families enrolled in the Framingham Children's Study with a child age to 6 years at baseline were followed into adolescence through yearly clinic visits and periodic data collection throughout each year. Dairy intake for these analyses was derived from a mean of 15 days of diet records per subject collected before age 6. A trained examiner took two measurements each year of height, weight, and triceps, subscapular, suprailiac, and abdominal skinfolds using a standardized protocol. Yearly change in body fat was estimated as the slope of these anthropometry measures from ages 5 to 13 years. Early adolescent body fat was estimated as the mean of all available measurements from 10 to 13 years of age.

RESULTS

Children in the lowest sex-specific tertile of dairy intake during preschool (i.e., <1.25 servings per day for girls and <1.70 servings per day for boys) had significantly greater gains in body fat during childhood. These children with low dairy intakes gained more than 3 additional mm of subcutaneous fat per year in the sum of four skinfold measures. By the time of early adolescence, those in the lowest tertile of dairy intake had a BMI that was approximately two units higher and an extra 25 mm of subcutaneous fat.

DISCUSSION

Suboptimal dairy intakes during preschool in this cohort were associated with greater gains in body fat throughout childhood.

Weight loss in overweight adults and the long-term risk of hypertension: the Framingham study

BACKGROUND

Few studies address long-term effects of weight loss on risk of incident hypertension among overweight adults.

METHODS

We evaluated weight loss among 623 overweight (body mass index [calculated as weight in kilograms divided by the square of height in meters] >/=25) middle-aged (aged 30-49 years) and 605 overweight older (aged 50-65 years) adults in Framingham, Mass. Subjects were classified first according to amount of weight lost over 4 years: (1) weight changed by less than 1.8 kg (stable weight), (2) lost 1.8 to less than 3.6 kg, (3) lost 3.6 to less than 6.8 kg, and (4) lost 6.8 kg or more. We also classified weight loss according to whether it was sustained during the next 4 years.

RESULTS

After adjusting for age, sex, education, baseline body mass index, height, activity, smoking, and alcohol intake, weight loss of 6.8 kg or more led to a 21% to 29% reduction in long-term hypertension risk. After adjusting for cancer or cardiovascular disease occurring during follow-up, weight loss of 6.8 kg or more led to a 28% reduction in risk (relative risk [95% confidence interval], 0.72 [0.49-1.05]) for middle-aged adults and a 37% reduction (0.63 [0.42-0.95]) for older adults. Sustained weight loss led to a 22% reduction in hypertension risk (0.78 [0.60-1.03]) among middle-aged and a 26% reduction (0.74 [0.56-0.97]) in older adults. This risk reduction was strengthened by adjustment for prevalent cancer or cardiovascular disease during follow-up.

CONCLUSION

A modest weight loss, particularly when sustained, substantially lowers the long-term risk of hypertension in overweight adults.

Intake of fruits, vegetables, and dairy products in early childhood and subsequent blood pressure change

BACKGROUND

Diets characterized by high intakes of fruits and vegetables and low-fat dairy products (for example, the DASH diet) have been shown to reduce blood pressure in adults. The effects of similar diets on children's blood pressure are unknown.

METHODS

We used 8 years of follow-up data from 95 children, initially 3 to 6 years of age at enrollment in the prospective Framingham Children's Study in 1986. The yearly clinic visits included 5 measures of blood pressure obtained with an automated device. Diet was assessed by means of replicate sets of 3-day food diaries during each year.

RESULTS

Children who consumed more fruits and vegetables (4 or more servings per day) or more dairy products (2 or more servings per day) during the preschool years had smaller yearly gains in systolic blood pressure throughout childhood. By the time of early adolescence, children with higher intakes of fruits and vegetables and dairy products had an adjusted mean (+/- standard deviation) systolic blood pressure of 106 +/- 2.9 mm Hg, whereas those with lower intakes in both food groups had a mean systolic blood pressure of 113 +/-1.5 mm Hg. Those with higher intakes of fruits and vegetables alone or dairy alone had intermediate levels of systolic blood pressure in adolescence. The effects on diastolic blood pressure were weaker.

CONCLUSION

These results suggest that a diet rich in fruits, vegetables, and dairy products may have beneficial effects on blood pressure during childhood.

BMI and waist circumference as predictors of lifetime colon cancer risk in Framingham Study adults

BACKGROUND

It is unclear whether the increased risk of colon cancer associated with obesity differs for men and women, by distribution of body fat, or by location of the tumor. The primary goal of this study was to address these questions.

METHODS

Eligible subjects from the Framingham Study cohort were classified according to body mass index (BMI) and waist size during two age periods: 30-54 y (n=3764) and 55-79 y (n=3802). All eligible men and women were cancer-free at baseline and had complete information on the following potential confounders: age, sex, education, height, activity, smoking, and alcohol. There were 157 incident lifetime cases of colon cancer among those followed beginning at 30-54 y of age and 149 lifetime cases among those whose follow up began at 55-79 y. Subjects were stratified further by gender, activity, and tumor location. The Cox Proportional Hazards Models were used to adjust for possible confounding by the above-described factors.

RESULTS

A BMI >/=30 led to a 50% increased risk (95% CI: 0.92-2.5) of colon cancer among middle-aged (30-54 y) and a 2.4-fold increased risk (95% CI: 1.5-3.9) among older (55-79 y) adults. The BMI effect was stronger for men than for women and for cases occurring in the proximal colon. These adverse effects generally diminished when waist was added to the multivariable models. A larger waist size (>/=99.1 cm (39 in) and 101.6 cm (40 in) for women and men, respectively) was associated with a two-fold increased risk of colon cancer; this risk increased linearly with increasing waist size and was evident for both proximal and distal colon cancer. There was no attenuation of these effects when BMI was added to the multivariable models. A larger waist had a particularly adverse effect among sedentary subjects (relative risk (RR)=4.4 for middle-aged adults; RR=3.0 for older adults).

CONCLUSION

These findings suggest that waist circumference is a stronger predictor of colon cancer risk than is BMI, and that central obesity is responsible for an increased risk of cancer of both the proximal and distal colon.

Does early physical activity predict body fat change throughout childhood?

BACKGROUND

Declining levels of physical activity in the population at large may be responsible in part for the rising rates of childhood obesity. Studies to date, however, have not consistently demonstrated such a protective effect. We used longitudinal data from the Framingham Children's Study (FCS) to address this important question.

METHODS

We used 8 years of activity monitoring (Caltrac electronic motion sensors) and repeated anthropometry measures for 103 children to examine the effect of activity on body fat change from preschool to early adolescence. Longitudinal data analysis methods were employed to account for the use of repeated measures on these children.

RESULTS

Children in the highest tertile of average daily activity from ages 4 to 11 years had consistently smaller gains in BMI, triceps, and sum of five skinfolds throughout childhood. By early adolescence (age 11), the sum of five skinfolds was 95.1, 94.5, and 74.1 for the low, middle, and high tertiles of activity, respectively (P for trend = 0.045). This protective effect of activity was evident for both girls and boys.

CONCLUSION

This longitudinal study adds strong support for the hypothesis that higher levels of physical activity during childhood lead to the acquisition of less body fat by the time of early adolescence.

Television viewing and change in body fat from preschool to early adolescence: The Framingham Children's Study

OBJECTIVE

To prospectively examine the relation between television watching and body fat change in children from preschool to early adolescence.

METHODS

In a longitudinal study, 106 children were enrolled during preschool years (mean age 4.0 y) and followed into early adolescence (mean age 11.1 y). Parents completed an annual questionnaire on the child's television and video habits. Body mass index (BMI), triceps skinfolds, and sum of five skinfolds were recorded yearly at annual clinic visits. Longitudinal statistical analyses were carried out using mixed modeling procedures to control for potential confounding by a number of factors.

RESULTS

Television watching was an independent predictor of the change in the child's BMI, triceps, and sum of five skinfolds throughout childhood. Its effect was only slightly attenuated by controlling for the baseline body fat, level of physical activity (as measured repeatedly by Caltrac accelerometer), percent of calories from fat, total calorie intake, or the parents' BMI or education. By age 11, children who watched 3.0 h or more of television per day had a mean sum of skinfolds of 106.2 mm, compared with a mean sum of skinfolds of 76.5 mm for those who watched less than 1.75 h per day (P=0.007). Furthermore, the adverse effect of television viewing was worse for those children who were also sedentary or had a higher-fat diet.

CONCLUSIONS

Children who watched the most television during childhood had the greatest increase in body fat over time. Healthy lifestyle education designed to prevent obesity and its consequences should target television-watching habits of children.

Folate intake and the risk of neural tube defects: an estimation of dose-response

BACKGROUND

Studies have shown that folic acid supplementation in early pregnancy markedly reduces the risk of neural tube defects (NTDs). Investigation of the relation between relative dose of supplemental folic acid or total folate intake and NTD risk is limited.

METHODS

We used data from 23,228 women, predominantly from the northeastern United States, enrolled between October 1984 and June 1987 in a prospective study of early prenatal exposures and pregnancy outcomes. Diet and vitamin intake data were gathered in the early second trimester. NTDs were ascertained through prenatal testing and by report of the delivering physician. Data analyses included multiple logistic regression and restricted spline regression modeling.

RESULTS

For each additional 500 dietary folate equivalents consumed per day, the prevalence of NTDs decreased by 0.78 cases (95% confidence interval [CI] = 0.47-1.09) per 1,000 pregnancies. Compared with women having the lowest total folate intakes (0-149 folate equivalents per day), the prevalence of NTDs declined by 34%, 30%, 56% and 77% among the offspring of those women consuming 150-399, 400-799, 800-1199 and > or = 1200 folate equivalents per day, respectively (P-value for linear trend = 0.016).

CONCLUSIONS

Our results suggest that NTD risk declines markedly with modest increases of total folate in early pregnancy. Total folate dose, rather than supplemental folate alone, should be considered in formulating public health guidelines for NTD prevention.

Chromosomal anomalies among the offspring of women with gestational diabetes

A limited body of data over the past 35 years has suggested that autoimmunity may be responsible for some cases of aneuploidy. The role of diabetes mellitus in the etiology of chromosomal anomalies has been infrequently studied. This study was designed to compare the prevalence of chromosome abnormalities among the offspring of women with gestational diabetes and the offspring of women without it. The authors used data from 7,332 women who underwent amniocentesis in a prospective study of pregnancy outcome (1984-1988) and examined the prevalence of autosomal and sex chromosome defects associated with gestational diabetes. Among the offspring of 231 women with gestational diabetes, the crude prevalence of chromosomal defects was twice as high as that seen in the offspring of 7,101 women without gestational diabetes. These anomalies were predominantly numeric sex chromosome defects. After adjusting for potential confounding by maternal age, body mass index, education, and first-trimester exposures in multiple logistic regression analysis, the authors found that women with gestational diabetes were 7.7 times as likely (95% confidence interval: 2.8, 21.1) to have an infant with a numeric sex chromosome defect as those without gestational diabetes. These results support the theory that some women who develop gestational diabetes may have underlying biochemical changes that induce nondisjunction and the development of chromosomal defects.

A prospective study of the risk of congenital defects associated with maternal obesity and diabetes mellitus

This study was designed to evaluate the effects of maternal obesity and diabetes mellitus on the risk of nonchromosomal congenital defects. We used data from 22,951 pregnant women enrolled in a prospective cohort study of early prenatal exposures and pregnancy outcome. The relative risks [prevalence ratios (PRs)] of major nonchromosomal congenital defects associated with obesity and diabetes, alone or in combination, were calculated using multiple logistic regression analysis. In this study, in the absence of diabetes, obese women (body mass index > or =28) had no higher risk, overall, of having an offspring with a major defect [PR = 0.95; 95% confidence interval (CI) = 0.62-1.5]. Their offspring, however, did have a higher prevalence of certain types of defects, including orofacial clefts; club foot; cardiac septal defects; and, to a lesser extent, hydrocephaly and abdominal wall defects. Women with pre-existing or gestational diabetes who were not obese also had no excess risk overall of having offspring affected by a major defect (PR = 0.98; 95% CI = 0.43-2.2), although they did have a higher prevalence of musculoskeletal defects. The pregnancies of women who were both obese and diabetic were 3.1 times as likely (95% CI = 1.2-7.6) to result in an offspring with a defect than were those of nonobese, nondiabetic women, which suggests that obesity and diabetes mellitus may act synergistically in the pathogenesis of congenital anomalies. The defects were largely craniofacial or musculoskeletal.