Prevalence Of Excess Body Fat Research Articles

Risk factors of overweight/obesity-related lifestyles in university students: Results from the EHU12/24 study.

This paper investigates the prevalence and interaction of overweight/obesity-related lifestyles (specifically, examining whether subjects meet the recommended criteria), in a representative sample of university students. This study is part of the project EHU12/24, an observational cross-sectional study, designed to assess the prevalence of excess body fat (BF) and major risk of developing overweight/obesity, according to a standardised protocol. In a cohort of 603 students, aged between 18 and 28 years, of the University of the Basque Country, information about meal patterns, diet quality, physical activity, sitting time, sleeping time, toxic habits and anthropometric measurements were collected. Sampling took place from February 2014 to May 2017. Binary logistic regression models adjusted for the covariates were utilised to test the association between lifestyles and risk of excess adiposity. The prevalence of overweight/obesity, according to BF percentage, was 14·4 %. The variables analysed related to meal pattern were associated with diet quality, and less healthy food habits were associated with other less health-related behaviours. Among men, moderate/low physical activity, breakfast skipping, non-adequate breakfast duration, number of eating occasions and eating breakfast alone/depending on the occasion were associated with excess BF, while among women, low MedDietScore, moderate/high alcohol consumption, non-adequate sleep duration, eating breakfast and lunch alone/depending on the occasion. Results suggest that certain unhealthy lifestyle behaviours coexist, interact with one another and increase the risk of overweight/obesity in this population. Sex-specific differences in risk factors of obesity have implications for interventions for primary prevention of obesity within this environment.

Body Fat Mass, Fat Distribution and Egg Consumption: a Population-Based Study in Chinese Adults

Objective: Egg is the vital source for many nutrients. The present study aimed to evaluate how egg consumption contributes to body fat mass and fat distribution in general Chinese adults.Methods: In a representative study of Chinese adults, 2241 rural adults aged 18–80 years completed physical measurements and semi quantitative food frequency questionnaire (FFQ). Body fat percentage (BF%) was estimated through validated Chinese-specific equations including age, body mass index (BMI), waist circumference (WC), gender and their interaction.Results: The prevalence of excessive body fat and central obesity in males were 44.2% and 31.3%, lower than that in females (60.7% and 36.1%, p < 0.05). 37.3% of lean or normal-weight individuals by BMI experienced excessive body fat given their BF% and 43.5% were central obesity according to WC. In females, egg consumption was associated with better body fat mass and its distribution. Compared with non-consumers, individuals consumed egg >50 g/d had a 34% lower risk of central obesity (OR:0.66, 0.39–0.99) and 38% lower risk of excessive body fat (OR:0.62, 0.37–1.00). There were significant dose-response relationships between egg consumption and overweight with excessive body fat/central obesity (p for linear trend <0.05). However, these associations were not significant in males.Conclusion: Our findings underscore the necessity for future public health guidelines to assess body fat mass and distribution simultaneously in Chinese adults. Egg consumption might be beneficial for weight regulation, especially for overweight with excessive body fat/central obesity in females. Further research is warrant to establish the causal inference.

Prevalence of excessive body fat among adolescents of a south Brazilian metropolitan region and State capital, associated risk factors, and consequences

BackgroundThe prevalence of overweight/obesity has become a major concern for public health in developing countries. Risk factors need to be well documented so that these countries develop public policies to fight the problem. Thus, the objective of this study is to determine the prevalence of excess fat among adolescents of a South Brazilian State Capital associated with risk factors and their consequences.MethodsThis study was conducted between 2014 and 2016 with adolescents aged 11–18 years. The following body composition measurements were collected: body mass, height, waist circumference, fat mass and bone mineral density (this latter through dual energy X-ray absorptiometry). Biochemical data as glucose, total cholesterol, and triglycerides were also collected. Finally, socioeconomic questionnaires were applied, as well as questionnaires regarding: the education level of guardians, active transportation, time spent with sedentary activities and physical activities. Odds ratios and chi-square test were applied in statistical analysis.ResultsData from 675 adolescents, from which 70% were males, were analyzed. The mean age was 14.7 ± 1.8 years. The prevalence of excess fat was 18.2% in boys and 92.1% in girls. As for sedentary lifestyle and physical inactivity, having one of these factors increased the risk of being overweight by 7.9 times for boys and 3.0 times for girls. In boys, there was a significant association between excess fat and waist circumference (p = 0.000; OR = 13.5; CI = 7.0–25.9), physical activity level (p = 0.000; OR = 4.0; CI = 2.5–6.5), triglycerides (p = 0.019; OR = 2.2; CI = 1.1–4.2) and total cholesterol (p = 0.000; OR = 2.6; CI = 1.6–4.5). In girls, there was an association between having excess fat and an increase in total cholesterol (p = 0.000; OR = 8.0; CI = 2.6–24.4).ConclusionsThe high prevalence of excess fat was greater than what was described by some studies conducted in developed countries. This reality demonstrates the need to implement public policies that can directly promote the reduction of sedentary habits and reinforce the importance of adopting an active lifestyle.

Factors associated with body adiposity index (BAI) in adults: population-based study

The objective of this study was to analyze factors associated with the body adiposity index. A population-based, cross-sectional study was conducted with 964 adults between 20 and 59 years of age, in Viçosa, State of Minas Gerais, Brazil. Household questionnaires and anthropometric measurements were applied to obtain data. Multiple analysis was performed using linear regression, adjusted for the sampling design effect. The prevalence of excess body adiposity was 36.89 (CI 30.81 to 43.43), being higher among men (48.18% - CI 39.09 to 57.34). Factors positively associated with body adiposity index were: female sex (p = 0.002); age in years (p < 0.001); those living with a partner (p = 0.022). Self-evaluation of positive health (p = 0.048) was negatively associated with the body adiposity index. The prevalence of excess body fat was high and the sex, age, marital status, health self-evaluation and dissatisfaction with body image were determinant factors to the increase in body adiposity in this population, indicating a marked risk for chronic diseases resulting from excess body fat.

Association between dietary intake, physical activity, socioeconomic factors and body fat percentage among schoolchildren

The scope of this article was to assess the association between dietary intake, physical activity and socioeconomic factors associated with body fat percentage in 7 to 14-year-old schoolchildren. It is a cross-sectional study with a probability sample of 2,481 students from public and private schools in Florianópolis, Santa Catarina, Brazil. Body fat percentage was investigated by measuring triceps and subscapular skin folds. Poisson regression was performed to test the association between excess body fat and independent variables, estimating prevalence ratios and 95% confidence intervals. The prevalence of excess body fat was 23.9%, though there was no significant difference between sex (p = 0.359) and age (p = 0.202). Excess body fat was associated with different factors in 11 to 14-year-old schoolchildren, namely eating less than three meals a day (OR = 1.62, CI: 1.38 to 1.91) and consumption of high-risk food more than 3 times a day (OR = 0.61 CI: 0.47 to 0.79). No significant difference was observed with physical activity. The high prevalence of excess body fat detected reveals the need for fostering the adoption of healthier behavioral practices (in relation to nutrition and physical activity) by schoolchildren.

Factors Associated with Excessive Body Fat in Men and Women: Cross-Sectional Data from Black South Africans Living in a Rural Community and an Urban Township.

ObjectiveTo determine the factors associated with excessive body fat among black African men and women living in rural and urban communities of South Africa.MethodsThis is a cross-sectional analysis of data from the Prospective Urban and Rural Epidemiology (PURE) study, Cape Town, South Africa conducted in 2009/2010. The study sample included 1220 participants (77.2% women) aged 35–70 years, for whom anthropometric measurements were obtained and risk factors documented through face-to-face interviews using validated international PURE study protocols. Sex-specific logistic regression models were used to evaluate socio-demographic, lifestyle and psychological factors associated with three excessive body fat indicators, namely body mass index (BMI), waist circumference (WC) and body fat percent (BF%).ResultsThe prevalence of excessive body fat based on BF%, WC and BMI cut-offs were 96.0%, 86.1%, and 81.6% for women respectively, and 62.2%, 25.9%, and 36.0% for men respectively. The significant odds of excessive body fat among the currently married compared to unmarried were 4.1 (95% CI: 1.3–12.5) for BF% and 1.9 (95% CI: 1.3–2.9) for BMI among women; and 4.9 (95% CI: 2.6–9.6), 3.2 (95% CI: 1.6–6.4) and 3.6 (95% CI: 1.9–6.8) for BF%, WC and BMI respectively among men. Age ≤50 years (compared to age >50 years) was inversely associated with excessive BF% in men and women, and less-than-a-college education was inversely associated with excessive BMI and WC in men. Tobacco smoking was inversely associated with all three excessive adiposity indicators in women but not in men. Unemployment, depression, and stress did not predict excessive body fat in men or women.ConclusionThe sex-differences in the socio-demographic and lifestyle factors associated with the high levels of excessive body fat in urban and rural women and men should be considered in packaging interventions to reduce obesity in these communities.

Body Composition, Physical Activity and Active Transportation in Adolescents of Metropolitan Region of Curitiba, Brazil

Background: Physical activity is a part of a healthy lifestyle, however sedentary habits are currently prevalent among adolescents which impacts rates of overweight and obesity in this group. This study aims to describe the relationship of physical activity with the use of active transportation to school (ATS) and its relationship with body composition in adolescents. Materials and Methods: Information about physical activity, sedentary behavior and active transportation were collected through two survey instruments, one completed by a responsible parent/guardian and other by the adolescent. Body composition was assessed by dual-energy x-ray absorptiometry (DXA). Excess body fat was defined as ≥ 25% in male and ≥ 30% among female adolescents. Less than 60 minutes of moderate to vigorous daily physical activity defined one as sedentary and greater than 2 hours of screen time per day was defined as excessive. Results: The prevalence of excess body fat was 46.5%. Only 24.7% of the sample performed recommended amounts of physical activity and 92.3% engaged in excess screen time. Approximately one-fifth of our sample (19.2%) used ATS. The main barriers to active transport were traffic, distance and safety. Those that used ATS had lower body fat and fewer hours of sedentary behavior.

Assessment of body composition by dual‐energy X‐ray absorptiometry, bioimpedance analysis and anthropometrics in children: the Physical Activity and Nutrition in Children study

We compared InBody720 segmental multifrequency bioimpedance analysis (SMF-BIA) with Lunar Prodigy Advance dual-energy X-ray absorptiometry (DXA) in assessment of body composition among 178 predominantly prepubertal children. Segmental agreement analysis of body compartments was carried out, and inter-relationships of anthropometric and other measures of body composition were defined. Moreover, the relations of different reference criteria for excess body fat were evaluated. The prevalence of excess body fat varies greatly according to the used criteria. Intraclass and Pearson's correlations between SMF-BIA and DXA were >0·92 in total body and >0·74 in regional measures. SMF-BIA underestimated percentage body fat (%BF) and fat mass (FM), and overestimated lean mass (LM) and percentage LM with significant offset trend bias. Higher adiposity increased offsets, and overall agreement was poorer in girls. On average, %BF offsets (girls/boys) and limits of agreement (LA) were 3·9/1·6% [(-)1·4-9·2%/(-)3·4-6·7%]. Interestingly percentage offsets of fat content (%BF: 18·9/10·1%, FM: 18·8/11·1%) showed no significant bias trends indicating that the corresponding absolute methodological offset depends on the amount of fat content. The smallest percentage offset was found with LM: 4·3/0·1%, referring offset (LA) of 0·88/0·03kg (±2·05/±1·71kg). Correspondingly, segmental LM had poorer agreement than total body LM. All anthropometrics except for the waist-to-hip ratio showed strong correlations (r=0·76-0·95) with abdominal and total body fat. Segmental multifrequency bioimpedance analysis is precise enough for total-LM analysis and had also sufficient trueness for total body composition analysis to be used in epidemiological purposes. There is need to generate scientifically and clinically relevant criteria and reference values for excess body fat.

Increase in prevalence of adiposity between the ages of 7 and 11 years reflects lower remission rates during this period

What is already known about this subject? A considerable increase in the prevalence of overweight during the primary school years (7-11 years) has been reported. What this study adds? This reflects lower remission rates of excess body fat (i.e. the proportion of shifts from excess to normal body fat) between the ages of 7 and 11 years as compared with nearly balanced incidence and remission rates of excess body fat between the ages of 3 and 7 years. This study aimed to compare the age-specific balance between incidence and remission of excess body fat between the ages of 3-7 and 7-11 years using the data from a longitudinal study. Longitudinal analysis based on the data from the Dortmund Nutritional and Anthropometric Longitudinally Designed (DONALD) Study, an ongoing, open cohort study in healthy children, conducted in Dortmund, Germany. Excess body fat was defined by the sum of triceps and subscapular skin-fold measurements above the 90th reference percentile of the new German standard; overweight was defined using different national and international standards. The main outcome parameters were incidence and remission rates of excess body fat (n = 496) and overweight (n = 518) between the ages of 3 and 7 years and between the ages of 7 and 11 years. The incidence rates of excess skin-fold thickness between the ages of 3 and 7 years (4.2 [2.4, 6.2]%) and between the ages of 7 and 11 years (4.3 [2.6, 6.2]%) were almost identical. By contrast, remission rates were significantly lower during the age period of 7-11 years (primary school age) than during the age period of 3-7 years (pre-school age): 37.5 (21.9, 53.1%) compared with 72.3 (59.6, 85.1%). These data point to the low remission of excess body fat as an important driving force for the increasing prevalence of excess body fat in children between the ages of 7 and 11 years. Public health initiatives in children should encompass both primary prevention and interventions targeted at children already overweight at school entry.

Prediction equations for fat and fat-free body mass in adolescents, based on body circumferences

Background: Fat mass (FM) and fat-free body mass (FFB) are important parameters for assessing nutritional status, since they are associated with higher prevalence of excess body fat and malnutrition worldwide.Aim: To develop prediction equations for fat and fat-free body mass in adolescents using body circumferences.Subjects and methods: This cross-sectional study included 218 adolescents (10–16 years) with normal weight as defined by body mass index. FMPred and FFBPred were estimated using stepwise multiple linear regression, considering age and body circumferences. Response variables, FMBIA and FFBBIA were estimated using bioelectric impedance analysis (BIA). The accuracy of the prediction equations was evaluated using the coefficient of determination (R2) and Akaike's Information Criterion (AIC).Results: The best prediction equations for males were FMPred = − 7.114 − 0.592(age) − 0.958(wrist)+0.191(hip)+0.295(abdomen); R2 = 0.552; AIC = 416.04 and FFBPred = − 52.180+1.913(age)+1.954(wrist)+1.635(forearm); R2 = 0.869; AIC = 578.24. For females, the best equations were FMPred = − 17.580 − 0.678(wrist)+0.221(abdomen)+0.241(hip)+0.202(proximal thigh) − 0.228(calf); R2 = 0.838; AIC = 415.36 and FFBPred = − 31.066+0.90(age)+1.090(wrist) − 0.139(abdomen)+0.326(hip)+0.632(calf); R2 = 0.878; AIC = 512.48.Conclusion: The equations developed to estimate fat body mass in females and fat-free body mass in both genders had high adjusted coefficients of determination and are therefore preferable to those derived using BIA.

Exceso de peso corporal infantil en Navarra y su repercusión en la adolescencia

Background and objective To estimate the prevalence of excess body fat in a cohort of children aged 2 to 14 years, and calculate the risk of overweight during adolescence when it was present in previous years. Subjects and method This was a retrospective study and review of clinical records including weight, height and body mass index in a cohort of 840 children at ages 2, 3, 4, 6, 8, 10, 12 y 14 years. The excess of body fat was calculated following the International Obesity Task Force criteria and showing the odds ratio of having overweight at age 14 years when it was present in any previous year. Results The prevalence of overweight at age 2 was 8.5%, increased progressively to 32.6% at age 8, and then decreased to 22.5% at age 14. The prevalence of overweight was significantly higher (p < 0.05) in females at age 2 and 3 years and lower (p < 0.05) at age 12 and 14 with respect to males. The probability of presenting overweight/obesity in adolescence was 15 times higher when overweight was present at age 8. Conclusions This study show that overweight at any paediatric age, especially school age, implies a high risk of overweight/obesity in adolescence.

Demographic and socioeconomic correlates of body fat assessed using DXA in US children and adolescents

Few studies examined the association between accurately measured body fat (BF) and socio‐demographic characteristics using nationally representative data in the US. We studied BF distribution and its association with socio‐demographic characteristics, including age, sex, race/ethnicity and poverty income ratio (PIR) in 8–19‐y‐old US youth in NHANES 1999–2004 (n = 7479). BF (measured by DXA) was used in continuous (%BF and fat mass index (FMI = fat mass/height2 (kg/m2)) and categorical (normal, overfat, and excess fat; using %BF cut points 25%, 30% for boys and 30%, 35% for girls) scales. The sex‐race‐specific prevalence of overfat+excess fat was: in boys, 45%, 33% and 57%; and in girls, 63%, 58% and 72%, in whites, blacks and Mexican Americans, respectively. Low‐income youth had higher %BF, FMI, overfat+excess fat rate. The distribution of %BF and FMI varied substantially by age, sex and ethnicity. After controlling for these factors, (1) one unit increase in PIR (scales 0 to 5‐high income) associated with a decrease by ~0.2 kg/m2 FMI, 0.5% (absolute) BF, and 14% (relative) in excess fat rate (P &lt; 0.001); (2) compared with participants with PIR ≥4, those with PIR &lt; 3 had an increase of ~1 kg/m2 FMI, 2% BF (absolute), and 70% (relative) in excess fat rate (P &lt; 0.001; P trend &lt; 0.05). Higher prevalence of excess body fat among US children from low‐income families calls for targeted strategies to fight pediatric obesity.Main source of research support: NIH/NIDDK (R01DK81335‐01A1), NIH/NICHD (1R01HD064685‐01A1, 1R03HD058077‐01A1, R03HD058077‐01A1S1), Vietnam Educational Foundation (VEF), and Thrasher Research Fund.

Muscular Strength Is Inversely Related to Prevalence and Incidence of Obesity in Adult Men

The purpose of the study was to determine the relation between quintiles of muscular strength after adjustment for age and body weight, and excessive body fat (EBF) and excessive abdominal fat (EAF) when controlling for cardiorespiratory fitness (CRF) and other potential confounders. A two-phased cross-sectional and longitudinal study was conducted assessing the prevalence and incidence of EBF and EAF across quintiles of muscular strength. The sample included 3,258 men (mean age = 42.2 ± 8.9; weight (kg) = 81.2 ± 11.0; BMI = 25.3 ± 2.9; %fat = 19.4 ± 5.8; waist girth (cm) = 91.2 ± 9.0) who completed at least two clinical examinations as part of the Aerobics Center Longitudinal Study (ACLS). Muscular strength was assessed with tests of upper and lower body muscular strength using rack-mounted weights with participants placed into strength quintiles. CRF was measured by a modified Balke treadmill test, %fat via underwater weighing or seven-site skinfold measurements, and waist girth measured at the level of the umbilicus. EBF was defined as ≥25% and EAF was defined as >102 cm. There was a strong inverse gradient across quintiles of muscular strength for prevalence and incidence of EBF and EAF (P trend <0.01, each). With the lowest quintile serving as the referent, reductions in risk of EBF and EAF exceeded 70% for the highest strength quintile. Evidence suggests muscular strength may provide protection from EBF and EAF and their related comorbidities.

Fast-food and sweetened beverage consumption: association with overweight and high waist circumference in adolescents

Overweight and obesity have increased to epidemic proportions among adolescents and are associated with chronic non-communicable diseases and excess mortality in adulthood. The association of overweight/obesity with poor dietary habits has not been studied in adolescents in middle-income developing countries. The present study aimed to estimate the prevalence of overweight, obesity and high waist circumference (WC) in 15-19-year-old Jamaican adolescents and to investigate the association with fast-food and sweetened beverage consumption. The study enrolled 1317 (598 male, 719 female) adolescents aged 15-19 years using multistage, nationally representative sampling. Age-specific prevalence calculation used internal Z-score lines connecting with the WHO adult cut-off points. Logistic regression was used to examine the association of overweight or high WC with fast-food and sweetened beverage consumption, adjusting for potential confounders. The overall prevalence of overweight, obesity and high WC was approximately 15 %, 6 % and 10 %, respectively. Prevalence estimated using internal Z-scores was similar to that using the International Obesity Taskforce cut-off points. Obesity (8.0 % in females, 3.3 % in males) and high WC (16.2 % in females, 1.7 % in males) were significantly more prevalent in females when using internal Z-score cut-offs. High WC was associated with the absence of fruit consumption (P = 0.043) and overweight with high sweetened beverage consumption (P = 0.018). Overweight occurs frequently among Jamaican 15-19-year-olds and is associated with increased consumption of sweetened beverages. High WC is more prevalent among females and is related to low consumption of fruits and vegetables. Measures to reduce the consumption of sweetened beverages and increase fruit intake may reduce the prevalence of excess body fat among adolescents.

Relation Between Muscular Strength and the Prevalence of Obesity: A Cross Sectional Analysis

Recent physical activity recommendations have included resistance training due to positive effects of increased muscular strength (MS), lean body mass and resting metabolic rate, and reduction in percent body fat (PFAT). The research that supports these recommendations tends to be of limited duration with little information on MS relations with health-related body composition parameters. PURPOSE: To determine the relations between MS and the prevalence of indicators of obesity as measured by PFAT and waist girth (WG). METHODS: The participants were men (n = 3,258, age range = 20 - 79 yrs) from the Aerobics Center Longitudinal Study that completed clinical examinations at The Cooper Clinic in Dallas, TX between 1980 and 1989. During the exam, PFAT, estimated through skinfold or hydrostatic weighing techniques, and WG were measured. Participants were considered to have excessive body fat (EBF) if PFAT was ≥25% and excessive abdominal fat (EAF) if WG > 102cm. The participants completed a treadmill test to estimate cardiorespiratory fitness (CRF) and 1 repetition maximums of the bench press and leg press on rack mounted weight equipment as measures of MS. An index of MS was calculated, which combined the two MS tests after controlling for age and body weight. The MS was then divided into quintiles (Q1 lowest - Q5 highest). Logistic regression was used to model the MS relations with EBF and EAF controlling age, body weight, smoking status, and CRF and produce relevant odds ratios (OR). RESULTS: Prevalence (%) of EBF and EAF, respectively, were Q1 (27, 15.2), Q2 (18, 11), Q3 (15, 9), Q4 (12, 10), and Q5 (8, 9). There was a strong inverse gradient (p<.001) between quintiles of MS and EBF with Q1as the referent, ORs (95% CIs) were 0.55 (0.39-0.78) in Q2, 0.47 (0.32-0.68) in Q3, 0.33 (0.23-0.48) in Q4, and 0.19 (0.12-0.29) in Q5. A significant inverse gradient (p<.01) between MS and EAF was present but only the OR (0.32,.95% CI = 0.18-0.59) for Q5 was significantly lower than Q1. CONCLUSION: MS demonstrated a significant inverse gradient with two indicators of obesity, EBF and EAF. This association was present after controlling important confounders including CRF and supports the use of resistance training to increase strength, lean body mass, resting metabolic rate and improve health-related body composition.

Genetic and environmental influences on body fat and blood pressure in African-American adult twins

African Americans have a particularly high prevalence of excessive body fat and high blood pressure. Genetic and environmental influences may be implicated for both of these risk factors. We investigated the potential for common genetic and environmental influences on body fat (waist circumference (WC), body mass index (BMI)) and blood pressure measures (systolic and diastolic pressure (SBP, DBP)) among African-American male and female subjects. Measurements were taken as part of the Carolina African-American Twin Study of Aging (CAATSA). The CAATSA sample contains 217 same-sex African-American male and female twins with average age of 47 years. This analysis included 39 monozygotic male pairs (MZ), 43 dizygotic male pairs (DZ); 63 MZ female pairs, and 72 DZ female pairs. Maximum likelihood quantitative genetic analyses were used. The total genetic variance for SBP was 22% in male subjects and 40.1% in female subjects. Of this total variance, 3.1% was in common with BMI in male subjects and 6% was in common with BMI in female subjects. After controlling for the effects of BMI, WC had less than 1% of its variance in common with SBP in male and female subjects. For DBP, the total genetic variance was 16.9% in male and 38.7% in female subjects. Of this total variance 6.1% was in common with BMI in male subjects and 3.7% was in common in female subjects. Again, WC had less than 1% of its genetic variance in common with DBP in both male and female subjects. The environmental variance common among these measures was also very small. The remaining variance was primarily accounted for by genetic and environmental effects unique to each measure as well as age. Based on the very small common genetic variance for BMI, SBP, and DBP as well as WC and the blood pressure measures, our results suggest that searching for common genes among these measures may be inconclusive.

Dietary fat and obesity: lack of an important role*

The percentage of dietary energy from fat has been suggested to be an important determinant of body fat, and this presumed effect has been used to promote low-fat diets. In short-term randomized trials, a small reduction in body weight is typically seen in individuals randomized to diets with a lower percentage of calories from fat. However, in trials lasting for 1 year or longer, fat consumption within the range of 18-40% of energy had consistently had little if any effect on body fatness. The weighted mean difference was -0.25 kg overall and +1.8 kg for trials with a control group that received a comparable intensity intervention (i.e. less weight loss on the low-fat diets). Moreover, in the USA and other affluent countries, a substantial decline in the percentage of energy from fat during the past two decades has corresponded with a massive increase in obesity. Diets high in fat do not account for the high prevalence of excess body fat in Western countries; red uctions in the percentage of energy from fat will have no important benefits and could further exacerbate this problem. Keywords: adiposity; diet; fat; obesity; overweight

Dietary fat and obesity: lack of an important role

The percentage of dietary energy from fat has been suggested to be an important determinant of body fat, and this presumed effect has been used to promote low-fat diets. In short-term randomized trials, a small reduction in body weight is typically seen in individuals randomized to diets with a lower percentage of calories from fat. However, in trials lasting for 1 year or longer, fat consumption within the range of 18-40% of energy had consistently had little if any effect on body fatness. The weighted mean difference was -0.25 kg overall and +1.8 kg for trials with a control group that received a comparable intensity intervention (i.e. less weight loss on the low-fat diets). Moreover, in the USA and other affluent countries, a substantial decline in the percentage of energy from fat during the past two decades has corresponded with a massive increase in obesity. Diets high in fat do not account for the high prevalence of excess body fat in Western countries; red uctions in the percentage of energy from fat will have no important benefits and could further exacerbate this problem. Keywords: adiposity; diet; fat; obesity; overweight

Dietary fat and obesity: lack of an important role

The percentage of dietary energy from fat has been suggested to be an important determinant of body fat, and this presumed effect has been used to promote low-fat diets. In short-term randomized trials, a small reduction in body weight is typically seen in individuals randomized to diets with a lower percentage of calories from fat. However, in trials lasting for 1 year or longer, fat consumption within the range of 18-40% of energy had consistently had little if any effect on body fatness. The weighted mean difference was -0.25 kg overall and +1.8 kg for trials with a control group that received a comparable intensity intervention (i.e. less weight loss on the low-fat diets). Moreover, in the USA and other affluent countries, a substantial decline in the percentage of energy from fat during the past two decades has corresponded with a massive increase in obesity. Diets high in fat do not account for the high prevalence of excess body fat in Western countries; red uctions in the percentage of energy from fat will have no important benefits and could further exacerbate this problem. Keywords: adiposity; diet; fat; obesity; overweight

Dietary fat is not a major determinant of body fat

The percentage of energy from fat in diets has been thought to be an important determinant of body fat, and several mechanisms have been proposed. Comparisons of diets and the prevalence of obesity between affluent and poor countries have been used to support this relationship, but these contrasts are seriously confounded by differences in physical activity and food availability. Within areas of similar economic development, regional intake of fat and prevalence of obesity have not been positively correlated. Randomized trials are the preferable method to evaluate the effect of dietary fat on adiposity and are feasible because the number of subjects needed is not large. In short-term trials, a modest reduction in body weight is typically seen in individuals randomized to diets with a lower percentage of calories from fat. However, compensatory mechanisms appear to operate, because in randomized trials lasting ≥1 year, fat consumption within the range of 18% to 40% of energy appears to have little if any effect on body fatness. The weighted mean difference was −0.25 kg overall and +1.8 kg (i.e., less weight loss on the low-fat diets) for trials with a control group that received a comparable intensity intervention. Moreover, within the United States, a substantial decline in the percentage of energy from fat during the last 2 decades has corresponded with a massive increase in the prevalence of obesity. Diets high in fat do not appear to be the primary cause of the high prevalence of excess body fat in our society, and reductions in fat will not be a solution.