Dietary strategies for the prevention of obesity

Association of quality and quantity of macronutrients intake with obesity, new anthropometric indices, lipid accumulation, and blood lipid risk index in Tehranian women

Background

This study examines the association between micronutrient intake, anthropometric indices, lipid accumulation, and blood lipid risk index among Tehranian women.

Methods

A cross-sectional study was conducted on 556 Tehranian women. Dietary intake was measured using a Food Frequency Questionnaire. Biochemical assessment and anthropometric indices were measured, and demographic information and physical activity were collected.

Results

Participants with the highest intake of carbohydrates were more prone to obesity. Conversely, those in the top tertile for protein intake had a lower likelihood of obesity and higher levels of lipid accumulation product (LAP). The highest fat consumers had a 63% decreased chance of having a high Castelli's Risk Index 1 (CRI-1). A higher glycemic index (GI) and glycemic load (GL) were linked to an increased probability of a high atherogenic coefficient (AC). Women in the top tertile of GL were significantly more likely to be obese and had lower odds for high LAP. Participants in the top tertile of aromatic amino acids/branched chain amino acids (AAA/BCAA) had significantly lower chances of high CRI-1 and a high atherogenic index of plasma (AIP). Those in the highest tertile of monounsaturated fatty acids/polyunsaturated fatty acids (MUFA/PUFA) had lower odds of obesity and high AIP.

Conclusions

The amount of carbohydrate (g) and protein intake (%), dietary GL, and the ratio of MUFA to PUFA were associated with obesity. The amount of fat intake (g) and AAA/BCAA indices were associated with CRI-1. LAP decreased with an increase in GL. AC increased with an increase in GI and GL. AAA/BCAA and MUFA/PUFA were associated with AIP.

Associations between feeding practices and child dietary quality, and the moderating effect of child eating behaviours on these associations

BACKGROUND

Parents' feeding practices are associated with children's food intake. Little is known about how children's eating behaviours (fussiness, enjoyment of food, food responsiveness, satiety responsiveness) moderate these associations. This study examines the relationships between feeding practices and pre-school children's dietary quality and whether children's eating behaviours moderate these relationships.

METHODS

In 2018, 1349 Australian mothers of children aged 2-5 years completed an online survey including validated measures of feeding practices (n = 9), child eating behaviours (n = 4) and dietary quality. Thirteen items from a food frequency questionnaire were summed as a measure of dietary quality. Linear regression assessed associations between feeding practices and dietary quality, including interactions between feeding practices and child eating behaviours.

RESULTS

The feeding practices positively associated with dietary quality were structured meal timing, monitoring, covert restriction, modelling healthy eating and structured meal setting (B coefficients: 0.63 to 2.70). The feeding practices inversely associated with dietary quality were overt restriction, persuasive feeding, reward for eating and reward for behaviour (B coefficients: -0.88 to -1.85). Child eating behaviours moderated associations between three feeding practices and dietary quality.

CONCLUSIONS

This exploratory study showed that some associations between feeding practices and child dietary quality were moderated by children's eating behaviours. The potential for tailoring nutrition promotion strategies for parents of children with differing eating behaviours should be further investigated.

Groups of mothers based on feeding practices and their associations with dietary quality of pre-school children: A latent profile analysis

Parents' feeding practices are associated with children's food intake. However, little is known about the patterns of feeding practices used by groups of mothers or how these groupings of practices influence children's dietary intake. Therefore, the aims of this study are to classify and describe groups of mothers according to their patterns of feeding practices and to examine the associations between the groups of maternal feeding practices and pre-school children's dietary quality. In 2018, 1349 mothers based in Australia of children aged 2-5 years completed an online survey including validated measures of nine feeding practices and dietary quality, measured using thirteen summed dietary items. Latent profile analysis was used to identify distinct groups of mothers who shared similar feeding practices. Linear regression models were fitted to examine associations between the feeding practice profiles and child dietary quality. A three-profile model was chosen based on interpretation, profile size and statistical model fit criteria. Profile 1 had lower mean scores of structure-related feeding practices than the other profiles; profile 2 had mean scores reflecting slightly higher use of most structure-related feeding practices and lower mean scores of some non-responsive feeding practices; profile 3 had higher mean scores of non-responsive feeding practices than the other profiles. Profile 1 (-2.95, CI: 3.97; -1.92) and profile 3 (-2.81, CI: 3.49; -2.13) had lower mean child dietary quality scores compared with profile 2. Profile 2, which reflected the most engagement in structure-related feeding practices combined with least non-responsive feeding practices, was associated with higher child diet quality, compared with the other two profiles. The identification of these unique profiles could help to tailor future interventions to consider patterns of feeding practices used by groups of mothers.

Causal relationship between dietary macronutrient composition and anthropometric measures: A bidirectional two-sample Mendelian randomization analysis

BACKGROUND

The question whether the proportion of energy provided by fat and carbohydrates in the diet is associated with body mass index (BMI) and waist circumference (WC) is an important public health issue, but determining causality is difficult in epidemiological studies.

OBJECTIVES

Using a two-sample bidirectional Mendelian randomization (MR) in both a univariable and multivariable setting, we aimed to determine whether the relative proportion of different macronutrients in the diet (in % of total energy intake (E%)) is causally related to BMI and WC and vice versa.

METHODS

All analyses were based on genome-wide association studies including 268,922 Europeans with dietary data (SSGAC Consortium) and at least 232,101 with anthropometric measures (GIANT Consortium). An inverse-variance weighted approach using modified second-order weights within the radial regression framework was performed. Radial MR-Egger, weighted median and mode, Robust Adjusted Profile Score (RAPS), and Pleiotropy RESidual Sum and Outlier (PRESSO) methods were used in sensitivity analyses to verify MR assumptions. Additionally, multivariable MR was conducted to account for inter correlation between macronutrient intakes. All estimates represent the standard deviation (SD) change in each outcome per one SD change in the respective exposure.

RESULTS

We found that genetically predicted relative carbohydrate intake (E%) reduced BMI (β = -0.529; 95% CI: -0.745, -0.312; P-value = 2⋅10^-6) and WC (β = -0.459; 95% CI: -0.656, -0.262; P-value = 5⋅10^-6). Both effects were also supported by the multivariable approach: β = -0.441 (95% CI: -0.772, -0.109; P-value = 0.009) for BMI and β = -0.410 (95% CI: -0.667, -0.154; P-value = 0.002) for WC. Genetically predicted dietary intake of fat (E%) was weaker and positively related to both anthropometric measures. We obtained evidence that a higher BMI and WC increased the relative dietary intake of fat and protein (E%). For example, each SD higher BMI increased protein intake (E%) by 0.114 SD (95% CI: 0.081, 0.147; P-value = 9⋅10^-12) and each SD higher WC increased protein intake (E%) by 0.078 SD (95% CI: 0.035, 0.121; P-value = 4⋅10^-4). Sensitivity analyses confirmed these findings revealing consistent effect estimates.

CONCLUSIONS

Using genetic information to improve causal inference we found evidence, that a low relative carbohydrate proportion (E%) and a high proportion of fat (E%) in the diet is causally related to a higher BMI and a higher WC. Further research considering carbohydrate, fat, and protein quality and possible consequences on micronutrient intake is needed to define the implications for dietary intake recommendations.

Daily intake of soft drinks is associated with symptoms of anxiety and depression in Chinese adolescents

OBJECTIVE

The association of soft drink consumption with mental problems in Asian adolescents has not been reported. The present study aimed to investigate the association of soft drink consumption and symptoms of anxiety and depression in adolescents in China.

DESIGN

A cross-sectional study to investigate the association of intake of soft drinks and sugars from soft drinks with symptoms of anxiety and depression measured by the two-item Generalized Anxiety Disorder (GAD-2) and the Patient Health Questionnaire (PHQ-2), respectively.

SETTING

A comprehensive university in Changsha, China.

PARTICIPANTS

Newly enrolled college students in 2017.

RESULT

In total, 8226 students completed the investigation and 8085 students with no systemic disorders were finally analysed. Students consuming soft drinks ≥7 times/week had significantly higher (mean difference; 95 % CI) GAD-2 (0·15; 0·07, 0·23) and PHQ-2 (0·27; 0·19, 0·35) scores compared with those barely consuming soft drinks, adjusted for demographic and behavioural factors. Those consuming >25 g sugar/d from soft drinks had significantly higher GAD-2 (0·11; 0·04, 0·18) and PHQ-2 (0·22; 0·15, 0·29) scores compared with non-consumers. The mediation effect of obesity in the associations was not clinically significant.

CONCLUSIONS

Adolescents consuming soft drinks ≥7 times/week, or >25 g sugar/d from soft drinks, had significantly higher levels of anxiety and depression. Dietary suggestion is needed to prevent anxiety and depression in adolescents.

Does high-carbohydrate intake lead to increased risk of obesity? A systematic review and meta-analysis

OBJECTIVES

The present study aimed to test the association between high and low carbohydrate diets and obesity, and second, to test the link between total carbohydrate intake (as a percentage of total energy intake) and obesity.

SETTING, PARTICIPANTS AND OUTCOME MEASURES

We sought MEDLINE, PubMed and Google Scholar for observation studies published between January 1990 and December 2016 assessing an association between obesity and high-carbohydrate intake. Two independent reviewers selected candidate studies, extracted data and assessed study quality.

RESULTS

The study identified 22 articles that fulfilled the inclusion and exclusion criteria and quantified an association between carbohydrate intake and obesity. The first pooled strata (high-carbohydrate versus low-carbohydrate intake) suggested a weak increased risk of obesity. The second pooled strata (increasing percentage of total carbohydrate intake in daily diet) showed a weak decreased risk of obesity. Both these pooled strata estimates were, however, not statistically significant.

CONCLUSIONS

On the basis of the current study, it cannot be concluded that a high-carbohydrate diet or increased percentage of total energy intake in the form of carbohydrates increases the odds of obesity. A central limitation of the study was the non-standard classification of dietary intake across the studies, as well as confounders like total energy intake, activity levels, age and gender. Further studies are needed that specifically classify refined versus unrefined carbohydrate intake, as well as studies that investigate the relationship between high fat, high unrefined carbohydrate-sugar diets.

PROSPERO REGISTRATION NUMBER

CRD42015023257.

Carbohydrate intake, obesity, metabolic syndrome and cancer risk? A two-part systematic review and meta-analysis protocol to estimate attributability

INTRODUCTION

Linkages between carbohydrates, obesity and cancer continue to demonstrate conflicting results. Evidence suggests inconclusive direct linkages between carbohydrates and specific cancers. Conversely, obesity has been strongly linked to a wide range of cancers. The purpose of the study is to explore linkages between carbohydrate intake and cancer types using a two-step approach. First the study will evaluate the linkages between carbohydrate intake and obesity, potentially stratified by metabolic syndrome status. Second, the estimated attributable fraction of obesity ascribed to carbohydrate intake will be multiplied against obesity attributable fractions for cancer types to give estimated overall attributable fraction for carbohydrate versus cancer type.

METHODS AND ANALYSIS

We will perform a comprehensive search to identify all possible published and unpublished studies that have assessed risk factors for obesity including dietary carbohydrate intake. Scientific databases, namely PubMed MEDLINE, EMBASE, EBSCOhost and ISI Web of Science will be searched. Following study selection, paper/data acquisition, and data extraction and synthesis, we will appraise the quality of studies and risk of bias, as well as assess heterogeneity. Meta-weighted attributable fractions of obesity due to carbohydrate intake will be estimated after adjusting for other potential confounding factors (eg, physical inactivity, other dietary intake). Furthermore, previously published systematic reviews assessing the cancer-specific risk associated with obesity will also be drawn. These estimates will be linked with the attributability of carbohydrate intake in part 1 to estimate the cancer-specific burden that can be attributed to dietary carbohydrates. This systematic review protocol has been developed according to the 'Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) 2015'.

ETHICS AND DISSEMINATION

The current study will be based on published literature and data, and, as such, ethics approval is not required. The final results of this two part systematic review (plus multiplicative calculations) will be published in a relevant international peer-reviewed journal.

TRIAL REGISTRATION NUMBER

PROSPERO CRD42015023257.

Energy and macronutrient intakes in Brazil: results of the first nationwide individual dietary survey

OBJECTIVE

To characterize energy and macronutrient intakes in Brazil and to describe the top food items contributing to energy and macronutrient intakes.

DESIGN

Two non-consecutive 24 h dietary records were collected and energy and macronutrient data were adjusted for usual intake distribution. Descriptive statistics and ANOVA with the Bonferroni post hoc test were analysed using SAS version 9·1. Means and standard deviations were estimated for sex, age and income strata.

SETTING

Nationwide cross-sectional survey, 2008-2009.

SUBJECTS

Nationally representative sample of individuals ≥10 years old (n32 749), excluding pregnant and lactating women (n 1254).

RESULTS

The average energy intake was 7958 kJ/d (1902 kcal/d) and mean energy density was 6·82 kJ/g (1·63 kcal/g). Added sugar represented 13 % of total energy intake and animal protein represented 10 %. The mean contribution of total fat to energy intake was 27 %, while the mean saturated fat contribution was 9 %. Compared with the lowest quartile of income, individuals in the highest income quartile had greater mean intakes of energy, added sugar, alcohol, animal protein, total fat, saturated fat, monounsaturated fat and trans fat. Rice, beans, beef, bread and coffee were among the top five foods contributing most to the intakes of energy, carbohydrates, protein, fat and fibre.

CONCLUSIONS

In general, Brazilians' dietary intake is compatible with a high risk of obesity and non-communicable chronic diseases, being characterized by high intakes of added sugar and saturated fat. Income may be a major determinant of diet nutritional characteristics.

Increasing Child Fruit and Vegetable Intake: Findings from the US Department of Agriculture Fresh Fruit and Vegetable Program

BACKGROUND

Fewer than 10% of US children and adolescents consume the recommended amounts of fruits and vegetables (F/V). The US Department of Agriculture's Fresh Fruit and Vegetable Program (FFVP) is intended to increase child F/V consumption by funding low-income schools to distribute free fresh F/V snacks outside of school mealtimes.

OBJECTIVE

The evaluation assessed FFVP effects on student F/V consumption and total energy intake in and out of school.

DESIGN

The evaluation employed a regression discontinuity design; that is, cross-sectional comparisons of a sample of students in schools just above and just below the FFVP funding cutoff for the program, which depended on the proportion of students eligible for free or reduced-price meals. During the 2010-2011 school year within a randomly selected sample of states, we selected schools in closest proximity to each state-specific FFVP funding cutoff. Interviewers conducted 24-hour diary-assisted recall interviews to assess dietary intake among children in selected schools.

PARTICIPANTS/SETTING

Participants were 4,696 students (grades 4 to 6) from 214 elementary schools in 16 randomly selected states.

STATISTICAL ANALYSES PERFORMED

Analysis proceeded via multivariate regression, comparing adjusted mean student intake in schools just above and just below the funding cutoff.

RESULTS

Adjusted mean daily F/V intake was one-third of a cup per day higher in FFVP-participating schools than in nonparticipating schools (0.32 cups per day; P<0.001), a difference of 15.5%. This included one-quarter cup higher daily F/V intake during school hours (0.26 cups; P<0.001) among students attending FFVP-participating schools. Fresh (but not total) F/V consumption also increased outside of school.

CONCLUSIONS

The FFVP increases child fresh and total F/V intake in school, and fresh F/V intake outside of school.

Energy density in the diet of workers from São Paulo, Brazil, and associated socio-demographic factors

OBJECTIVE

This paper aims at analyzing the energy density (ED) of the diet of workers from the city of São Paulo, Southeastern Brazil, and the way this is associated with socio-demographic characteristics, as well as evaluating the relationship between ED and nutrient intake.

METHODS

A cross-sectional study evaluated the diet of 852 workers using the 24-hour dietary recall; one recall was applied to all individuals and a second one was applied to a sub-sample in order to adjust intrapersonal variability. The ED of the diet was calculated using three methods: inclusion of all solid foods and beverages, excluding water (ED 1); inclusion of all solid foods and beverages containing at least 5 kcal/100g (ED 2); and inclusion of all solid foods, excluding all beverages (ED 3). Linear regression was used to analyze the relationship between ED and socio-demographic variables and the relationship between ED and nutrients was evaluated using Pearson coefficient correlation.

RESULTS

Considering the workers' diet, the ED values observed were 1.18 kcal/g, 1.22 kcal/g and 1.73 kcal/g for the ED 1, ED 2, ED 3 methods, respectively. In the multiple regression models, only the age variable was maintained in the final model and showed an inverse association with all ED methods. ED 3 showed an increase in energy density for non-white individuals. Of all studied nutrients, protein was the only one that was not significantly correlated with ED 3 (p = 0.899).

CONCLUSION

The young adults studied had a higher energy-density diet, representing a priority group for nutrition interventions. Regardless of the calculation method used, there is a correlation between ED and nutrients.

Parenting style and dietary behaviour of young children. Findings from the Healthy Beginnings Trial

Parenting style may have a role in the development of young children's dietary behaviour, and a better understanding of parenting style may lead to better-targeted childhood obesity prevention interventions. This study aimed to investigate the association of parental self-efficacy, parenting style and dietary behaviour of young children. A cross-sectional study with 242 first-time mothers and their children was conducted using the data from the Healthy Beginnings Trial undertaken in one of the most socially and economically disadvantaged areas of south-western Sydney, in 2007-2010. Parental self-efficacy, parenting style (warmth and hostility) and children's dietary behaviours (consumption of vegetables, fruit, soft-drink and snacks) were assessed by face-to-face interviews with participating mothers in the control group when their children were 2 years old. Logistic regression analysis was conducted to examine the association between parenting style and the child's dietary behaviour. Mothers with higher levels of global parental self-efficacy and self-efficacy for an infant were more likely to report their children had 2 serves of vegetables per day, with odds ratio (OR) 2.40 (95%CI 1.35-4.27, P=0.003) and OR 1.88 (95%CI 1.06-3.36, P=0.03), respectively. A higher level of global parental self-efficacy or self-efficacy for an infant was significantly associated with having 2 serves of fruit per day with adjusted odds ratio (AOR) 2.46 (95%CI 1.35-4.48, P=0.003) and AOR 1.85 (95%CI 1.00-3.41, P=0.048), respectively, after adjusting for annual household income. Mothers with a higher level of parental warmth were more likely to report their children had 2 serves of vegetable per day with OR 1.85 (95%CI 1.06-3.25, P=0.03). Parental self-efficacy and parenting style were associated, cross-sectionally, with important children's dietary behaviours. Interventions which target parental self-efficacy and parenting style may improve eating habits of young children, and contribute to childhood obesity prevention.

Different dietary strategies for weight loss in obesity: role of energy and macronutrient content

Obesity is a chronic disorder caused by an imbalance of the energy metabolism with high associated burdens. Therefore, huge efforts are being currently devoted in studying new types of hypoenergetic diets and their composition, in order to characterise more specific, long-lasting and safe slimming protocols. A number of investigations are trying to determine the specific influence of the macronutrient distribution in energy-restricted diets on the management of excessive body weight. In this context, very-low-energy diets supplying between 1670 and 3350 kJ (400 and 800 kcal)/d have been beneficial in short-term treatments causing a weight loss of 300-500 g/d. Such strategies place more emphasis on energy restriction than on the macronutrient composition of the diet prescription. Weight loss produced by either low-carbohydrate or low-fat moderately energy-restricted diets ranges from 0.5 to 1.0 kg/week, while diets with high or moderately high protein content have also been applied in weight-reducing programmes by inducing losses of 0.2-0.4 kg/week. Other factors that determine weight loss by dieting are sex, age, initial body weight, race, genetics, regional fat deposition, etc, which must be taken into account to explain the variability in the outcomes of different low-energy diets. Therefore, more research is needed about the impact of diets with different fuel substrates and foods on the characteristics of the weight-loss process.

Binge eating and other eating behaviors among patients on treatment for psychoses in India

OBJECTIVE

'Medication-induced eating disorder' is implicated as one of the reasons for the weight gain seen in psychotic patients. The aim of this study was to examine the prevalence of binge eating disorder (BED), binge spectrum and other eating behaviors in patients on treatment for non-affective psychoses in India.

METHOD

An outpatient cross-sectional study of 73 participants.

RESULTS

Most of the binge spectrum behaviors occurred in patients on treatment for more than 2 years and on concomitant antidepressant medication. Patients admitted to obesogenic eating behaviour more readily than actual calorie intake. BED was absent in our sample.

CONCLUSION

While binge spectrum eating behaviors were noted in many patients, the absence of BED was striking and could be due to cultural factors. Binge spectrum eating behaviors could be treatment emergent or linked particularly to the improvement from psychoses and post psychotic depression.

Is sugar consumption detrimental to health? A review of the evidence 1995-2006

Many countries set quantitative targets for added sugars, justifying this by expressing concern about the likely impact of sugar on weight control, dental health, diet quality, or metabolic syndrome. This review considers whether current intakes of sugar are harmful to health, and analyses recent literature using a systematic approach to collate, rank, and evaluate published studies from 1995-2006. Results from high quality obesity studies did not suggest a positive association between body mass index and sugar intake. Some studies, specifically on sweetened beverages, highlighted a potential concern in relation to obesity risk, although these were limited by important methodological issues. Diet adequacy appeared to be achieved across sugar intakes of 6 to 20% energy, depending on subject age. Studies on metabolic syndrome reported no adverse effects of sugar in the long-term, even at intakes of 40-50% energy. The evidence for colorectal cancer suggested an association with sugar, but this appeared to have been confounded by energy intake and glycemic load. There was no credible evidence linking sugar with attention-deficit, dementia, or depression. Regarding dental caries, combinations of sugar amount/frequency, fluoride exposure, and food adhesiveness were more reliable predictors of caries risk than the amount of sugar alone. Overall, the available evidence did not support a single quantitative sugar guideline covering all health issues.

Metabolic effects of low glycaemic index diets

The persistence of an epidemic of obesity and type 2 diabetes suggests that new nutritional strategies are needed if the epidemic is to be overcome. A promising nutritional approach suggested by this thematic review is metabolic effect of low glycaemic-index diet. The currently available scientific literature shows that low glycaemic-index diets acutely induce a number of favorable effects, such as a rapid weight loss, decrease of fasting glucose and insulin levels, reduction of circulating triglyceride levels and improvement of blood pressure. The long-term effect of the combination of these changes is at present not known. Based on associations between these metabolic parameters and risk of cardiovascular disease, further controlled studies on low-GI diet and metabolic disease are needed.

Contribution of Midparental BMI and other determinants of obesity in adult offspring

The aim of this study was to evaluate midparental BMI among intergenerational factors associated with obesity in adult offspring. The data was from an unusual two-generational observational design of 1,477 married couples from Renfrew and Paisley in Scotland who were aged 45-64 years when screened in 1972-1976, and 1,040 sons and 1,298 daughters aged 30-59 years when screened in 1996. BMI was categorized as normal (< 25 kg/m(2)), overweight (25-29.9 kg/m(2)), and obese (> or = 30 kg/m(2)) in offspring and parents. Midparental BMI was defined as the mean of the mother's and father's BMI. Low physical activity, nonsmoking status, higher cholesterol level, and manual social class were all associated with increased BMI in offspring. The effect of reported dietary intake was less clear. Offspring of obese parents (defined by midparental BMI) were over four times more likely to be obese than offspring of normal weight parents. Midparental BMI had a strong effect on offspring BMI, independent of social class, smoking habit, physical activity, and reported dietary intake. Adding midparental BMI to the regression model more than doubled the explained variation of offspring BMI from 7.7 to 17%. Every 1 kg/m(2) increment in midparental BMI was associated with a BMI greater by 0.51 kg/m(2) in offspring. We conclude that midparental BMI is a useful simple tool to predict offspring BMI. Whether it represents genetic or environmental family effects, it is easily ascertained by the individual and could be used in health promotion and clinical settings to target individuals who are at increased risk of becoming obese.

Macronutrient distribution over a period of 23 years in relation to energy intake and body fatness

The distribution of the four macronutrients is associated with energy intake and body fatness according to short-term interventions. The present study involves macronutrient distribution in relation to energy intake and body fatness over a period of 23 years in individuals who have ad libitum access to food. Eight follow-up measurements have been performed in 168 men and 182 women who participate in the Amsterdam Growth and Health Longitudinal Study. From the age of 13 years onwards, dietary intake, physical activity and the thickness of four skinfolds have been assessed. Body fatness was assessed using dual-energy X-ray absorptiometry at the age of 36 years. Generalised estimating equation regression analyses showed that energy percentages (En%) from protein and (in men) carbohydrates were inversely related to energy intake, while the En% from fat was positively related with energy intake. The men and women with high body fatness at the age of 36 years had a 1 En% higher protein intake, and the women with high body fatness had a 2 En% lower alcohol intake at the age of 32 and 36 years. The apparent inconsistent relationships between protein and energy intake and protein and body fatness can in women be explained by reverse causation and underreporting, as in women, low energy intake could not be explained by low physical activity. In conclusion, high intake of protein and (in men) carbohydrate, and low intake of fat are inversely related to total energy intake. High body fatness at the age of 36 years is related to a higher protein intake and, in women, to a lower alcohol intake.

Should snacks be recommended in obesity treatment? a 1-year randomized clinical trial

OBJECTIVE

To study the effect to recommend no snacks vs three snacks per day on 1-year weight loss. The hypothesis was that it is easier to control energy intake and lose weight if snacks in between meals are omitted.

SUBJECTS/METHOD

In total 140 patients (36 men, 104 women), aged 18-60 years and body mass index>30 kg/m(2) were randomized and 93 patients (27 men, 66 women) completed the study. A 1-year randomized intervention trial was conducted with two treatment arms with different eating frequencies; 3 meals/day (3M) or 3 meals and 3 snacks/day (3+3M). The patients received regular and individualized counseling by dieticians. Information on eating patterns, dietary intake, weight and metabolic variables was collected at baseline and after 1 year.

RESULTS

Over 1 year the 3M group reported a decrease in the number of snacks whereas the 3+3M group reported an increase (-1.1 vs +0.4 snacks/day, respectively, P<0.0001). Both groups decreased energy intake and E% (energy percent) fat and increased E% protein and fiber intake but there was no differences between the groups. Both groups lost weight, but there was no significant difference in weight loss after 1 year of treatment (3M vs 3+3M=-4.1+/-6.1 vs -5.9+/-9.4 kg; P=0.31). Changes in metabolic variables did not differ between the groups, except for high-density lipoprotein that increased in the 3M group but not in 3+3M group (P<0.033 for group difference).

CONCLUSION

Recommending snacks or not between meals does not influence 1-year weight loss.

The aetiology of childhood obesity: a review

Whilst the prevention of childhood obesity is the only viable, enduring, cost-effective solution to the obesity epidemic, effective methods for it remain elusive. Furthermore, strategies to influence obesogenic environments remain relatively unexplored. In order to be able to develop powerful population-level interventions and public health policies to prevent childhood obesity, it is important to understand its aetiology and those environments that are most amenable to measurable change. First, the present paper considers why we should be concerned about obesity in children, from both the perspective of the increased health risk to the individual and the high economic cost of treatment of obesity and related diseases, highlighting why the prevention of childhood obesity is important. Next, the determinants of health behaviour and the obesogenic environment are explored, which helps us to understand why the aetiology is so complex and that potential causal factors should not be considered in isolation, as the interaction between these factors is also important. The paper then considers the multi-factorial aetiology of childhood obesity and the rationale for the increasing trends in obesity that are evident, in order to understand what is changing in society and our children's behaviour that is triggering the positive energy balance leading to obesity. The review emphasises the need for multi-level approaches if we truly want to prevent childhood obesity. It also serves to highlight that there is a need to extend the current research base in order to build a well-founded framework to form the basis of a strategy for the prevention of childhood obesity.

Popular weight-loss diets: from evidence to practice

The increasing number of overweight and obese individuals has become one of the leading public health concerns in many countries around the world. Concomitant with this increase in the prevalence of obesity has been the rise in the number of weight-loss diets, many of which alter macronutrient composition, but with the majority focused on carbohydrate restriction. Low-carbohydrate diets are attractive because they promise rapid weight loss without having to count calories and compromise the consumption of many palatable foods. By contrast, traditional dietary recommendations for weight loss endorse a fat-restricted and calorie-restricted diet high in complex carbohydrates. Evidence indicates that low-carbohydrate diets could be better in terms of short-term weight loss relative to traditional low-fat diets, but little is known about their long-term utility and safety. Diets based on the traditional Mediterranean dietary pattern are becoming increasingly popular because of their healthful benefits, particularly regarding cardiovascular outcomes. Mediterranean diets encourage consumption of a variety of palatable foods, optimizing adherence and sustainability. In this Review we discuss the current evidence on the efficacy of low-fat, low-carbohydrate and Mediterranean dietary patterns for weight loss, their potential mechanisms of action and important clinical considerations.