Background
Child overweight and obesity has increased globally, and can be associated with short‐ and long‐term health consequences.
Objectives
To assess the effects of diet, physical activity, and ...behavioural interventions for the treatment of overweight or obesity in preschool children up to the age of 6 years.
Search methods
We performed a systematic literature search in the databases Cochrane Library, MEDLINE, EMBASE, PsycINFO, CINAHL, and LILACS, as well as in the trial registers ClinicalTrials.gov and ICTRP Search Portal. We also checked references of identified trials and systematic reviews. We applied no language restrictions. The date of the last search was March 2015 for all databases.
Selection criteria
We selected randomised controlled trials (RCTs) of diet, physical activity, and behavioural interventions for treating overweight or obesity in preschool children aged 0 to 6 years.
Data collection and analysis
Two review authors independently assessed risk of bias, evaluated the overall quality of the evidence using the GRADE instrument, and extracted data following the Cochrane Handbook for Systematic Reviews of Interventions. We contacted trial authors for additional information.
Main results
We included 7 RCTs with a total of 923 participants: 529 randomised to an intervention and 394 to a comparator. The number of participants per trial ranged from 18 to 475. Six trials were parallel RCTs, and one was a cluster RCT. Two trials were three‐arm trials, each comparing two interventions with a control group. The interventions and comparators in the trials varied. We categorised the comparisons into two groups: multicomponent interventions and dietary interventions. The overall quality of the evidence was low or very low, and six trials had a high risk of bias on individual 'Risk of bias' criteria. The children in the included trials were followed up for between six months and three years.
In trials comparing a multicomponent intervention with usual care, enhanced usual care, or information control, we found a greater reduction in body mass index (BMI) z score in the intervention groups at the end of the intervention (6 to 12 months): mean difference (MD) ‐0.3 units (95% confidence interval (CI) ‐0.4 to ‐0.2); P < 0.00001; 210 participants; 4 trials; low‐quality evidence, at 12 to 18 months' follow‐up: MD ‐0.4 units (95% CI ‐0.6 to ‐0.2); P = 0.0001; 202 participants; 4 trials; low‐quality evidence, and at 2 years' follow‐up: MD ‐0.3 units (95% CI ‐0.4 to ‐0.1); 96 participants; 1 trial; low‐quality evidence.
One trial stated that no adverse events were reported; the other trials did not report on adverse events. Three trials reported health‐related quality of life and found improvements in some, but not all, aspects. Other outcomes, such as behaviour change and parent‐child relationship, were inconsistently measured.
One three‐arm trial of very low‐quality evidence comparing two types of diet with control found that both the dairy‐rich diet (BMI z score change MD ‐0.1 units (95% CI ‐0.11 to ‐0.09); P < 0.0001; 59 participants) and energy‐restricted diet (BMI z score change MD ‐0.1 units (95% CI ‐0.11 to ‐0.09); P < 0.0001; 57 participants) resulted in greater reduction in BMI than the comparator at the end of the intervention period, but only the dairy‐rich diet maintained this at 36 months' follow‐up (BMI z score change in MD ‐0.7 units (95% CI ‐0.71 to ‐0.69); P < 0.0001; 52 participants). The energy‐restricted diet had a worse BMI outcome than control at this follow‐up (BMI z score change MD 0.1 units (95% CI 0.09 to 0.11); P < 0.0001; 47 participants). There was no substantial difference in mean daily energy expenditure between groups. Health‐related quality of life, adverse effects, participant views, and parenting were not measured.
No trial reported on all‐cause mortality, morbidity, or socioeconomic effects.
All results should be interpreted cautiously due to their low quality and heterogeneous interventions and comparators.
Authors' conclusions
Muticomponent interventions appear to be an effective treatment option for overweight or obese preschool children up to the age of 6 years. However, the current evidence is limited, and most trials had a high risk of bias. Most trials did not measure adverse events. We have identified four ongoing trials that we will include in future updates of this review.
The role of dietary interventions is more equivocal, with one trial suggesting that dairy interventions may be effective in the longer term, but not energy‐restricted diets. This trial also had a high risk of bias.
Dietary modification remains key to successful weight loss. Yet, no one dietary strategy is consistently superior to others for the general population. Previous research suggests genotype or ...insulin-glucose dynamics may modify the effects of diets.
To determine the effect of a healthy low-fat (HLF) diet vs a healthy low-carbohydrate (HLC) diet on weight change and if genotype pattern or insulin secretion are related to the dietary effects on weight loss.
The Diet Intervention Examining The Factors Interacting with Treatment Success (DIETFITS) randomized clinical trial included 609 adults aged 18 to 50 years without diabetes with a body mass index between 28 and 40. The trial enrollment was from January 29, 2013, through April 14, 2015; the date of final follow-up was May 16, 2016. Participants were randomized to the 12-month HLF or HLC diet. The study also tested whether 3 single-nucleotide polymorphism multilocus genotype responsiveness patterns or insulin secretion (INS-30; blood concentration of insulin 30 minutes after a glucose challenge) were associated with weight loss.
Health educators delivered the behavior modification intervention to HLF (n = 305) and HLC (n = 304) participants via 22 diet-specific small group sessions administered over 12 months. The sessions focused on ways to achieve the lowest fat or carbohydrate intake that could be maintained long-term and emphasized diet quality.
Primary outcome was 12-month weight change and determination of whether there were significant interactions among diet type and genotype pattern, diet and insulin secretion, and diet and weight loss.
Among 609 participants randomized (mean age, 40 SD, 7 years; 57% women; mean body mass index, 33 SD, 3; 244 40% had a low-fat genotype; 180 30% had a low-carbohydrate genotype; mean baseline INS-30, 93 μIU/mL), 481 (79%) completed the trial. In the HLF vs HLC diets, respectively, the mean 12-month macronutrient distributions were 48% vs 30% for carbohydrates, 29% vs 45% for fat, and 21% vs 23% for protein. Weight change at 12 months was -5.3 kg for the HLF diet vs -6.0 kg for the HLC diet (mean between-group difference, 0.7 kg 95% CI, -0.2 to 1.6 kg). There was no significant diet-genotype pattern interaction (P = .20) or diet-insulin secretion (INS-30) interaction (P = .47) with 12-month weight loss. There were 18 adverse events or serious adverse events that were evenly distributed across the 2 diet groups.
In this 12-month weight loss diet study, there was no significant difference in weight change between a healthy low-fat diet vs a healthy low-carbohydrate diet, and neither genotype pattern nor baseline insulin secretion was associated with the dietary effects on weight loss. In the context of these 2 common weight loss diet approaches, neither of the 2 hypothesized predisposing factors was helpful in identifying which diet was better for whom.
clinicaltrials.gov Identifier: NCT01826591.
Colonic fermentation of dietary fibre to short-chain fatty acids (SCFA) influences appetite hormone secretion in animals, but SCFA production is excessive in obese animals. This suggests there may be ...resistance to the effect of SCFA on appetite hormones in obesity.
To determine the effects of inulin (IN) and resistant starch (RS) on postprandial SCFA, and gut hormone (glucagon-like peptide (GLP-1), peptide-tyrosine-tyrosine (PYY) and ghrelin) responses in healthy overweight/obese (OWO) vs lean (LN) humans.
Overnight-fasted participants (13 OWO and 12 LN) consumed 300 ml water containing 75 g glucose (GLU) as control or 75 g GLU plus 24 g IN, or 28.2 g RS using a randomised, single-blind, cross-over design. Blood for appetite hormones and SCFA was collected at intervals over 6 h. A standard lunch was served 4 h after the test drink.
Relative to GLU, IN, but not RS, significantly increased SCFA areas under the curve (AUC) from 4-6 h (AUC
). Neither IN nor RS affected GLP-1 or PYY-AUC
. Although neither IN nor RS reduced ghrelin-AUC
compared with GLU, ghrelin at 6 h after IN was significantly lower than that after GLU (P<0.05). After IN, relative to GLU, the changes in SCFA-AUC
were negatively related to the changes in ghrelin-AUC
(P=0.017). SCFA and hormone responses did not differ significantly between LN and OWO.
Acute increases in colonic SCFA do not affect GLP-1 or PYY responses in LN or OWO subjects, but may reduce ghrelin. The results do not support the hypothesis that SCFA acutely stimulate PYY and GLP-1 secretion; however, a longer adaptation to increased colonic fermentation or a larger sample size may yield different results.
Overweight and obesity are significant public health concerns that are linked to numerous negative health consequences. Physical activity is an important lifestyle behavior that contributes to body ...weight regulation.
Physical activity is inversely associated with weight gain and the incidence of obesity. Physical activity also contributes to additional weight loss when coupled with dietary modification, and it can result in modest weight loss when not coupled with dietary modification. Moreover, physical activity is associated with improved long-term weight loss and prevention of weight gain following initial weight loss. Current evidence supports that physical activity should be moderate to vigorous in intensity to influence body weight regulation. There is also a growing body of evidence that physical activity can be accumulated throughout the day in shorter periods of time rather than being performed during a structured and longer period, and that physical activity performed in this manner can be important for body weight regulation.
The literature supports the inclusion of physical activity as an important lifestyle behavior for regulating body weight. There are multiple intervention approaches that may be effective for enhancing physical activity engagement within the context of weight control.
Obese children are vulnerable to vitamin D deficiency and impaired cardiovascular health; vitamin D replenishment might improve their cardiovascular health.
The aims were to determine, in vitamin ...D–deficient overweight and obese children, whether supplementation with vitamin D3 1000 or 2000 IU/d is more effective than 600 IU/d in improving arterial endothelial function, arterial stiffness, central and systemic blood pressure (BP), insulin sensitivity (1/fasting insulin concentration), fasting glucose concentration, and lipid profile and to explore whether downregulation of adipocytokines and markers of systemic inflammation underlies vitamin D effects.
We conducted a randomized, double-masked, controlled clinical trial in 225 10- to 18-y-old eligible children. Change in endothelial function at 6 mo was the primary outcome.
Dose–response increases in serum 25-hydroxyvitamin D concentrations were significant and tolerated without developing hypercalcemia. Changes at 3 and 6 mo in endothelial function, arterial stiffness, systemic-systolic BP, lipids, and inflammatory markers did not differ between children receiving 1000 or 2000 IU vitamin D and children receiving 600 IU. Some secondary outcomes differed between groups. Compared with the 600-IU group, central-systolic, central-diastolic, and systemic-diastolic BP was lower at 6 mo in the 1000-IU group −2.66 (95% CI: −5.27, −0.046), −3.57 (−5.97, −1.17), and −3.28 (−5.55, −1.00) mm Hg, respectively; insulin sensitivity increased at 3 and 6 mo and fasting glucose concentration declined at 6 mo (−2.67; 95% CI: −4.88, −0.46 mg/dL) in the 2000-IU group.
Correction of vitamin D deficiency in overweight and obese children by vitamin D3 supplementation with 1000 or 2000 IU/d versus 600 IU/d did not affect measures of arterial endothelial function or stiffness, systemic inflammation, or lipid profile, but resulted in reductions in BP and fasting glucose concentration and in improvements in insulin sensitivity. Optimization of children’s vitamin D status may improve their cardiovascular health. This trial was registered at clinicaltrials.gov as NCT01797302.
The long-term impact of intentional weight loss on cardiovascular events remains unknown. We describe 12-month changes in body weight and cardiovascular risk factors in PREvención con DIeta ...MEDiterránea (PREDIMED)-Plus, a trial designed to evaluate the long-term effectiveness of an intensive weight loss lifestyle intervention on primary cardiovascular prevention.
Overweight/obese adults with metabolic syndrome aged 55-75 years (
= 626) were randomized to an intensive weight loss lifestyle intervention based on an energy-restricted Mediterranean diet, physical activity promotion, and behavioral support (IG) or a control group (CG). The primary and secondary outcomes were changes in weight and cardiovascular risk markers, respectively.
Diet and physical activity changes were in the expected direction, with significant improvements in IG versus CG. After 12 months, IG participants lost an average of 3.2 kg vs. 0.7 kg in the CG (
< 0.001), a mean difference of -2.5 kg (95% CI -3.1 to -1.9). Weight loss ≥5% occurred in 33.7% of IG participants compared with 11.9% in the CG (
< 0.001). Compared with the CG, cardiovascular risk factors, including waist circumference, fasting glucose, triglycerides, and HDL cholesterol, significantly improved in IG participants (
< 0.002). Reductions in insulin resistance, HbA
, and circulating levels of leptin, interleukin-18, and MCP-1 were greater in IG than CG participants (
< 0.05). IG participants with prediabetes/diabetes significantly improved glycemic control and insulin sensitivity, along with triglycerides and HDL cholesterol levels compared with their CG counterparts.
PREDIMED-Plus intensive lifestyle intervention for 12 months was effective in decreasing adiposity and improving cardiovascular risk factors in overweight/obese older adults with metabolic syndrome, as well as in individuals with or at risk for diabetes.
To evaluate the association of ultra-processed food (UPF) consumption with gains in weight and waist circumference, and incident overweight/obesity, in the Brazilian Longitudinal Study of Adult ...Health (ELSA-Brasil) cohort.
We applied FFQ at baseline and categorized energy intake by degree of processing using the NOVA classification. Height, weight and waist circumference were measured at baseline and after a mean 3·8-year follow-up. We assessed associations, through Poisson regression with robust variance, of UPF consumption with large weight gain (1·68 kg/year) and large waist gain (2·42 cm/year), both being defined as ≥90th percentile in the cohort, and with incident overweight/obesity.
Brazil.
Civil servants of Brazilian public academic institutions in six cities (n 11 827), aged 35-74 years at baseline (2008-2010).
UPF provided a mean 24·6 (sd 9·6) % of ingested energy. After adjustment for smoking, physical activity, adiposity and other factors, fourth (>30·8 %) v. first (<17·8 %) quartile of UPF consumption was associated (relative risk (95 % CI)) with 27 and 33 % greater risk of large weight and waist gains (1·27 (1·07, 1·50) and 1·33 (1·12, 1·58)), respectively. Similarly, those in the fourth consumption quartile presented 20 % greater risk (1·20 (1·03, 1·40)) of incident overweight/obesity and 2 % greater risk (1·02; (0·85, 1·21)) of incident obesity. Approximately 15 % of cases of large weight and waist gains and of incident overweight/obesity could be attributed to consumption of >17·8 % of energy as UPF.
Greater UPF consumption predicts large gains in overall and central adiposity and may contribute to the inexorable rise in obesity seen worldwide.
Saturated fatty acid (SFA) vs polyunsaturated fatty acid (PUFA) may promote nonalcoholic fatty liver disease by yet unclear mechanisms.
To investigate if overeating SFA- and PUFA-enriched diets lead ...to differential liver fat accumulation in overweight and obese humans.
Double-blind randomized trial (LIPOGAIN-2). Overfeeding SFA vs PUFA for 8 weeks, followed by 4 weeks of caloric restriction.
General community.
Men and women who are overweight or have obesity (n = 61).
Muffins, high in either palm (SFA) or sunflower oil (PUFA), were added to the habitual diet.
Lean tissue mass (not reported here). Secondary and exploratory outcomes included liver and ectopic fat depots.
By design, body weight gain was similar in SFA (2.31 ± 1.38 kg) and PUFA (2.01 ± 1.90 kg) groups, P = 0.50. SFA markedly induced liver fat content (50% relative increase) along with liver enzymes and atherogenic serum lipids. In contrast, despite similar weight gain, PUFA did not increase liver fat or liver enzymes or cause any adverse effects on blood lipids. SFA had no differential effect on the accumulation of visceral fat, pancreas fat, or total body fat compared with PUFA. SFA consistently increased, whereas PUFA reduced circulating ceramides, changes that were moderately associated with liver fat changes and proposed markers of hepatic lipogenesis. The adverse metabolic effects of SFA were reversed by calorie restriction.
SFA markedly induces liver fat and serum ceramides, whereas dietary PUFA prevents liver fat accumulation and reduces ceramides and hyperlipidemia during excess energy intake and weight gain in overweight individuals.
Obesity is common in children and adolescents in the United States, is associated with negative health effects, and increases the likelihood of obesity in adulthood.
To systematically review the ...benefits and harms of screening and treatment for obesity and overweight in children and adolescents to inform the US Preventive Services Task Force.
MEDLINE, PubMed, PsycINFO, Cochrane Collaboration Registry of Controlled Trials, and the Education Resources Information Center through January 22, 2016; references of relevant publications; government websites. Surveillance continued through December 5, 2016.
English-language trials of benefits or harms of screening or treatment (behavior-based, orlistat, metformin) for overweight or obesity in children aged 2 through 18 years, conducted in or recruited from health care settings.
Two investigators independently reviewed abstracts and full-text articles, then extracted data from fair- and good-quality trials. Random-effects meta-analysis was used to estimate the benefits of lifestyle-based programs and metformin.
Weight or excess weight (eg, body mass index BMI; BMI z score, measuring the number of standard deviations from the median BMI for age and sex), cardiometabolic outcomes, quality of life, other health outcomes, harms.
There was no direct evidence on the benefits or harms of screening children and adolescents for excess weight. Among 42 trials of lifestyle-based interventions to reduce excess weight (N = 6956), those with an estimated 26 hours or more of contact consistently demonstrated mean reductions in excess weight compared with usual care or other control groups after 6 to 12 months, with no evidence of causing harm. Generally, intervention groups showed absolute reductions in BMI z score of 0.20 or more and maintained their baseline weight within a mean of approximately 5 lb, while control groups showed small increases or no change in BMI z score, typically gaining a mean of 5 to 17 lb. Only 3 of 26 interventions with fewer contact hours showed a benefit in weight reduction. Use of metformin (8 studies, n = 616) and orlistat (3 studies, n = 779) were associated with greater BMI reductions compared with placebo: -0.86 (95% CI, -1.44 to -0.29; 6 studies; I2 = 0%) for metformin and -0.50 to -0.94 for orlistat. Groups receiving lifestyle-based interventions offering 52 or more hours of contact showed greater improvements in blood pressure than control groups: -6.4 mm Hg (95% CI, -8.6 to -4.2; 6 studies; I2 = 51%) for systolic blood pressure and -4.0 mm Hg (95% CI, -5.6 to -2.5; 6 studies; I2 = 17%) for diastolic blood pressure. There were mixed findings for insulin or glucose measures and no benefit for lipids. Medications showed small or no benefit for cardiometabolic outcomes, including fasting glucose level. Nonserious harms were common with medication use, although discontinuation due to adverse effects was usually less than 5%.
Lifestyle-based weight loss interventions with 26 or more hours of intervention contact are likely to help reduce excess weight in children and adolescents. The clinical significance of the small benefit of medication use is unclear.
To investigate the association between eating behaviours (eating speed and energy intake of main meals) and overweight in pre-school children.
Cross-sectional study. Data consisted of measurements ...(height and weight), questionnaire information (eating behaviours of eating speed and overeating) and on-site observation data (meal duration and energy intake of main meals).
Seven kindergartens in Beijing, China.
Pre-school children (n 1138; age range 3·1-6·7 years old) from seven kindergartens participated in the study.
The multivariate-adjusted odds ratio of overweight in participants with parent-reported 'more than needed food intake' was 3·02 (95 % CI 2·06, 4·44) compared with the 'medium food intake' participants, and higher eating speed was associated with childhood overweight. For the two observed eating behaviours, each 418·7 kJ (100 kcal) increase of lunch energy intake significantly increased the likelihood for overweight by a factor of 1·445, and each 5-min increase in meal duration significantly decreased the likelihood for overweight by a factor of 0·861. Increased portions of rice and cooked dishes were significantly associated with overweight status (OR = 2·274; 95 % CI 1·360, 3·804 and OR = 1·378; 95 % CI 1·010, 1·881, respectively).
Eating speed and excess energy intake of main meals are associated with overweight in pre-school children.
PDF
