Breakfast frequency and development of metabolic risk

OBJECTIVE

The relation of breakfast intake frequency to metabolic health is not well studied. The aim of this study was to examine breakfast intake frequency with incidence of metabolic conditions.

RESEARCH DESIGN AND METHODS

We performed an analysis of 3,598 participants from the community-based Coronary Artery Risk Development in Young Adults (CARDIA) study who were free of diabetes in the year 7 examination when breakfast and dietary habits were assessed (1992-1993) and participated in at least one of the five subsequent follow-up examinations over 18 years.

RESULTS

Relative to those with infrequent breakfast consumption (0-3 days/week), participants who reported eating breakfast daily gained 1.9 kg less weight over 18 years (P=0.001). In a Cox regression analysis, there was a stepwise decrease in risk across conditions in frequent breakfast consumers (4-6 days/week) and daily consumers. The results for incidence of abdominal obesity, obesity, metabolic syndrome, and hypertension remained significant after adjustment for baseline measures of adiposity (waist circumference or BMI) in daily breakfast consumers. Hazard ratios (HRs) and 95% CIs for daily breakfast consumption were as follows: abdominal obesity HR 0.78 (95% CI 0.66-0.91), obesity 0.80 (0.67-0.96), metabolic syndrome 0.82 (0.69-0.98), and hypertension 0.84 (0.72-0.99). For type 2 diabetes, the corresponding estimate was 0.81 (0.63-1.05), with a significant stepwise inverse association in black men and white men and women but no association in black women. There was no evidence of differential results for high versus low overall dietary quality.

CONCLUSIONS

Daily breakfast intake is strongly associated with reduced risk of a spectrum of metabolic conditions.

Pregnancy weight gain and childhood body weight: a within-family comparison

BACKGROUND

Excessive pregnancy weight gain is associated with obesity in the offspring, but this relationship may be confounded by genetic and other shared influences. We aimed to examine the association of pregnancy weight gain with body mass index (BMI) in the offspring, using a within-family design to minimize confounding.

METHODS AND FINDINGS

In this population-based cohort study, we matched records of all live births in Arkansas with state-mandated data on childhood BMI collected in public schools (from August 18, 2003 to June 2, 2011). The cohort included 42,133 women who had more than one singleton pregnancy and their 91,045 offspring. We examined how differences in weight gain that occurred during two or more pregnancies for each woman predicted her children's BMI and odds ratio (OR) of being overweight or obese (BMI≥85th percentile) at a mean age of 11.9 years, using a within-family design. For every additional kg of pregnancy weight gain, childhood BMI increased by 0.0220 (95% CI 0.0134-0.0306, p<0.0001) and the OR of overweight/obesity increased by 1.007 (CI 1.003-1.012, p = 0.0008). Variations in pregnancy weight gain accounted for a 0.43 kg/m(2) difference in childhood BMI. After adjustment for birth weight, the association of pregnancy weight gain with childhood BMI was attenuated but remained statistically significant (0.0143 kg/m(2) per kg of pregnancy weight gain, CI 0.0057-0.0229, p = 0.0007).

CONCLUSIONS

High pregnancy weight gain is associated with increased body weight of the offspring in childhood, and this effect is only partially mediated through higher birth weight. Translation of these findings to public health obesity prevention requires additional study. Please see later in the article for the Editors' Summary.

Effects of dietary glycemic index on brain regions related to reward and craving in men

BACKGROUND

Qualitative aspects of diet influence eating behavior, but the physiologic mechanisms for these calorie-independent effects remain speculative.

OBJECTIVE

We examined effects of the glycemic index (GI) on brain activity in the late postprandial period after a typical intermeal interval.

DESIGN

With the use of a randomized, blinded, crossover design, 12 overweight or obese men aged 18-35 y consumed high- and low-GI meals controlled for calories, macronutrients, and palatability on 2 occasions. The primary outcome was cerebral blood flow as a measure of resting brain activity, which was assessed by using arterial spin-labeling functional magnetic resonance imaging 4 h after test meals. We hypothesized that brain activity would be greater after the high-GI meal in prespecified regions involved in eating behavior, reward, and craving.

RESULTS

Incremental venous plasma glucose (2-h area under the curve) was 2.4-fold greater after the high- than the low-GI meal (P = 0.0001). Plasma glucose was lower (mean ± SE: 4.7 ± 0.14 compared with 5.3 ± 0.16 mmol/L; P = 0.005) and reported hunger was greater (P = 0.04) 4 h after the high- than the low-GI meal. At this time, the high-GI meal elicited greater brain activity centered in the right nucleus accumbens (a prespecified area; P = 0.0006 with adjustment for multiple comparisons) that spread to other areas of the right striatum and to the olfactory area.

CONCLUSIONS

Compared with an isocaloric low-GI meal, a high-GI meal decreased plasma glucose, increased hunger, and selectively stimulated brain regions associated with reward and craving in the late postprandial period, which is a time with special significance to eating behavior at the next meal. This trial was registered at clinicaltrials.gov as NCT01064778.

A low-glycemic-load versus low-fat diet in the treatment of fatty liver in obese children

BACKGROUND

Fatty liver is highly prevalent among obese children and represents a major risk factor for chronic liver diseases and severe metabolic complications.

METHODS

We randomly assigned 17 obese children 8-17 years of age with fatty liver to either an experimental low-glycemic-load or conventional low-fat diet for 6 months. Participants in both groups received nutrition education and behavioral counseling of equal intensity. The primary outcome was hepatic lipid content measured by proton magnetic resonance spectroscopy. Secondary outcomes included change in visceral fat, BMI, anthropometrics, alanine aminotransferase (ALT), and insulin resistance.

RESULTS

A total of 16 participants completed the study. Reported glycemic load decreased in the low-glycemic-load group and reported dietary fat decreased in the low-fat group. At baseline, liver fat was 23.8% [standard deviation (SD) 12.2] in the low-glycemic-load group and 29.3% (14.1) in the low-fat group. Liver fat decreased substantially in both groups at 6 months expressed as absolute percentage change, with no between-group differences [-8.8 (standard error (SE) 4.1) vs. -10.5 (3.7)%, respectively, p=0.76 for group×time interaction]. Secondary outcomes also improved on both diets, with no between-group differences. Baseline and change in ALT were strongly associated with hepatic fat content.

CONCLUSIONS

Weight-reducing diets focused either on glycemic load or dietary fat improved hepatic steatosis over 6 months. Additional research is needed to determine whether these diets differ in effectiveness over the long term.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00480922.

Effects of a low glycemic load or a low-fat dietary intervention on body weight in obese Hispanic American children and adolescents: a randomized controlled trial

BACKGROUND

In Hispanic children and adolescents, the prevalence of obesity and insulin resistance is considerably greater than in non-Hispanic white children. A low-glycemic load diet (LGD) has been proposed as an effective dietary intervention for pediatric obesity, but to our knowledge, no published study has examined the effects of an LGD in obese Hispanic children.

OBJECTIVE

We compared the effects of an LGD and a low-fat diet (LFD) on body composition and components of metabolic syndrome in obese Hispanic youth.

DESIGN

Obese Hispanic children (7-15 y of age) were randomly assigned to consume an LGD or an LFD in a 2-y intervention program. Body composition and laboratory assessments were obtained at baseline and 3, 12, and 24 mo after intervention.

RESULTS

In 113 children who were randomly assigned, 79% of both groups completed 3 mo of treatment; 58% of LGD and 55% of LFD subjects attended 24-mo follow-up. Compared with the LFD, the LGD decreased the glycemic load per kilocalories of reported food intakes in participants at 3 mo (P = 0.02). Both groups had a decreased BMI z score (P < 0.003), which was expressed as a standard z score relative to CDC age- and sex-specific norms, and improved waist circumference and systolic blood pressure (P < 0.05) at 3, 12, and 24 mo after intervention. However, there were no significant differences between groups for changes in BMI, insulin resistance, or components of metabolic syndrome (all P > 0.5).

CONCLUSIONS

We showed no evidence that an LGD and an LFD differ in efficacy for the reduction of BMI or aspects of metabolic syndrome in obese Hispanic youth. Both diets decreased the BMI z score when prescribed in the context of a culturally adapted, comprehensive weight-reduction program.

A randomized trial of sugar-sweetened beverages and adolescent body weight

BACKGROUND

Consumption of sugar-sweetened beverages may cause excessive weight gain. We aimed to assess the effect on weight gain of an intervention that included the provision of noncaloric beverages at home for overweight and obese adolescents.

METHODS

We randomly assigned 224 overweight and obese adolescents who regularly consumed sugar-sweetened beverages to experimental and control groups. The experimental group received a 1-year intervention designed to decrease consumption of sugar-sweetened beverages, with follow-up for an additional year without intervention. We hypothesized that the experimental group would gain weight at a slower rate than the control group.

RESULTS

Retention rates were 97% at 1 year and 93% at 2 years. Reported consumption of sugar-sweetened beverages was similar at baseline in the experimental and control groups (1.7 servings per day), declined to nearly 0 in the experimental group at 1 year, and remained lower in the experimental group than in the control group at 2 years. The primary outcome, the change in mean body-mass index (BMI, the weight in kilograms divided by the square of the height in meters) at 2 years, did not differ significantly between the two groups (change in experimental group minus change in control group, -0.3; P=0.46). At 1 year, however, there were significant between-group differences for changes in BMI (-0.57, P=0.045) and weight (-1.9 kg, P=0.04). We found evidence of effect modification according to ethnic group at 1 year (P=0.04) and 2 years (P=0.01). In a prespecified analysis according to ethnic group, among Hispanic participants (27 in the experimental group and 19 in the control group), there was a significant between-group difference in the change in BMI at 1 year (-1.79, P=0.007) and 2 years (-2.35, P=0.01), but not among non-Hispanic participants (P>0.35 at years 1 and 2). The change in body fat as a percentage of total weight did not differ significantly between groups at 2 years (-0.5%, P=0.40). There were no adverse events related to study participation.

CONCLUSIONS

Among overweight and obese adolescents, the increase in BMI was smaller in the experimental group than in the control group after a 1-year intervention designed to reduce consumption of sugar-sweetened beverages, but not at the 2-year follow-up (the prespecified primary outcome). (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; ClinicalTrials.gov number, NCT00381160.).

Best Practice Guidelines in Pediatric/Adolescent Weight Loss Surgery

OBJECTIVE

To establish evidence-based guidelines for best practices in pediatric/adolescent weight loss surgery (WLS).

RESEARCH METHODS AND PROCEDURES

We carried out a systematic search of English-language literature in MEDLINE on WLS performed on children and adolescents. Key words were used to narrow the field for a selective review of abstracts. Data were extracted, and evidence categories were assigned according to a grading system based on established evidence-based models. Eight pertinent case series, published between 1980 and 2004, were identified and reviewed. These data were supplemented with expert opinions and literature on WLS in adults.

RESULTS

Recommendations focused on patient safety, reduction of medical errors, systems improvements, credentialing, and future research. We developed evidence-based criteria for eligibility, assessment, treatment, and follow-up; recommended surgical procedures based on the best available evidence; and established minimum guideline requirements for data collection.

DISCUSSION

Lack of adequate data and gaps in knowledge were cited as important reasons for caution. Physiological status, comprehensive screening of patients and their families, and required education and counseling were identified as key factors in assessing eligibility for surgery. Data collection and peer review were also identified as important issues in the delivery of best practice care.

Effects of dietary composition on energy expenditure during weight-loss maintenance

CONTEXT

Reduced energy expenditure following weight loss is thought to contribute to weight gain. However, the effect of dietary composition on energy expenditure during weight-loss maintenance has not been studied.

OBJECTIVE

To examine the effects of 3 diets differing widely in macronutrient composition and glycemic load on energy expenditure following weight loss.

DESIGN, SETTING, AND PARTICIPANTS

A controlled 3-way crossover design involving 21 overweight and obese young adults conducted at Children's Hospital Boston and Brigham and Women's Hospital, Boston, Massachusetts, between June 16, 2006, and June 21, 2010, with recruitment by newspaper advertisements and postings.

INTERVENTION

After achieving 10% to 15% weight loss while consuming a run-in diet, participants consumed an isocaloric low-fat diet (60% of energy from carbohydrate, 20% from fat, 20% from protein; high glycemic load), low-glycemic index diet (40% from carbohydrate, 40% from fat, and 20% from protein; moderate glycemic load), and very low-carbohydrate diet (10% from carbohydrate, 60% from fat, and 30% from protein; low glycemic load) in random order, each for 4 weeks.

MAIN OUTCOME MEASURES

Primary outcome was resting energy expenditure (REE), with secondary outcomes of total energy expenditure (TEE), hormone levels, and metabolic syndrome components.

RESULTS

Compared with the pre-weight-loss baseline, the decrease in REE was greatest with the low-fat diet (mean [95% CI], -205 [-265 to -144] kcal/d), intermediate with the low-glycemic index diet (-166 [-227 to -106] kcal/d), and least with the very low-carbohydrate diet (-138 [-198 to -77] kcal/d; overall P = .03; P for trend by glycemic load = .009). The decrease in TEE showed a similar pattern (mean [95% CI], -423 [-606 to -239] kcal/d; -297 [-479 to -115] kcal/d; and -97 [-281 to 86] kcal/d, respectively; overall P = .003; P for trend by glycemic load < .001). Hormone levels and metabolic syndrome components also varied during weight maintenance by diet (leptin, P < .001; 24-hour urinary cortisol, P = .005; indexes of peripheral [P = .02] and hepatic [P = .03] insulin sensitivity; high-density lipoprotein [HDL] cholesterol, P < .001; non-HDL cholesterol, P < .001; triglycerides, P < .001; plasminogen activator inhibitor 1, P for trend = .04; and C-reactive protein, P for trend = .05), but no consistent favorable pattern emerged.

CONCLUSION

Among overweight and obese young adults compared with pre-weight-loss energy expenditure, isocaloric feeding following 10% to 15% weight loss resulted in decreases in REE and TEE that were greatest with the low-fat diet, intermediate with the low-glycemic index diet, and least with the very low-carbohydrate diet.

TRIAL REGISTRATION

clinicaltrials.gov Identifier: NCT00315354.

Health-related quality of life in adolescents with or at risk for type 2 diabetes mellitus

OBJECTIVE

To evaluate how adolescents with or at risk for type 2 diabetes mellitus (T2DM) and their parent/guardians (parents) perceive adolescents' health-related quality of life.

STUDY DESIGN

We interviewed overweight/obese, 12- to 18-year-old youth with T2DM, prediabetes, or insulin resistance and one parent from 5 US sites. Assessments included Pediatric Quality of Life Inventory (PedsQL), Health Utilities Index, family conflict, and diabetes burden.

RESULTS

In 108 adolescents, diagnoses included 40.7% with T2DM, 25.0% with prediabetes, and 34.3% with insulin resistance. PedsQL summary score (SS) was higher in adolescents than parents (P=.02). Parents rated physical functioning lower than adolescents (P<.0001), but there were no differences in psychosocial health. Adolescent PedsQL SS did not differ with diagnosis, but was inversely associated with adolescent body mass index z-score (P=.0004) and family conflict (P<.0001) and associated with race/ethnicity (P<.0001). Number of adolescent co-morbidities (P=.007) and burden of diabetes care (P<.05) were inversely associated with parent PedsQL SS. There were no differences in the Health Utilities Index-Mark 3 multi-attribute utility score.

CONCLUSIONS

Parents perceive their adolescents' physical functioning as more impaired than adolescents themselves. Contextual factors including severity of obesity, race/ethnicity, family conflict, and burden of diabetes care influence health-related quality of life. Family-based approaches to treatment and prevention of T2DM may benefit from increased attention to the biopsychosocial context.

Estimated morbidity and mortality in adolescents and young adults diagnosed with Type 2 diabetes mellitus

AIMS

To estimate remaining life expectancy (RLE), quality-adjusted life expectancy (QALE), causes of death and lifetime cumulative incidence of microvascular/macrovascular complications of diabetes for youths diagnosed with Type 2 diabetes.

METHODS

A Markov-like computer model simulated the life course for a hypothetical cohort of adolescents/young adults in the USA, aged 15-24 years, newly diagnosed with Type 2 diabetes following either conventional or intensive treatment based on the UK Prospective Diabetes Study. Outcomes included RLE, discounted QALE in quality-adjusted life years (QALYs), cumulative incidence of microvascular/macrovascular complications and causes of death.

RESULTS

Compared with a mean RLE of 58.6 years for a 20-year-old in the USA without diabetes, conventional treatment produced an average RLE of 43.09 years and 22.44 discounted QALYs. Intensive treatment afforded an incremental 0.98 years and 0.44 discounted QALYs. Intensive treatment led to lower lifetime cumulative incidence of all microvascular complications and lower mortality from microvascular complications (e.g. end-stage renal disease (ESRD) death 19.4% vs. 25.2%). Approximately 5% with both treatments had ESRD within 25 years. Lifetime cumulative incidence of coronary heart disease (CHD) increased with longer RLE and greater severity of CHD risk factors. Incorporating disutility (loss in health-related quality of life) of intensive treatment resulted in net loss of QALYs.

CONCLUSIONS

Adolescents/young adults with Type 2 diabetes lose approximately 15 years from average RLE and may experience severe, chronic complications of Type 2 diabetes by their 40s. The net clinical benefit of intensive treatment may be sensitive to preferences for treatment. A comprehensive management plan that includes early and aggressive control of cardiovascular risk factors is likely needed to reduce lifetime risk of CHD.

Weight loss strategies for adolescents: a 14-year-old struggling to lose weight

With prevalence approaching 20% in the United States, adolescent obesity has become a common problem for patients, parents, and clinicians. Obese adolescents may experience physical and psychosocial complications, as illustrated by the case of Ms K, a 14-year-old girl with a body mass index of 40. Unfortunately, the effectiveness of pediatric obesity treatment is modest in younger children and declines in older children and adolescents, and few interventions involving adolescents have produced significant long-term weight loss. Nevertheless, novel strategies to alter energy balance have shown preliminary evidence of benefit in clinical trials, including a diet focused on food quality rather than fat restriction and a lifestyle approach to encourage enjoyable physical activity throughout the day rather than intermittent exercise. Parents can have an important influence on weight-related behaviors in adolescents despite typically complicated emotional dynamics at this age, especially through the use of noncoercive methods. A key parenting practice applicable to children of all ages is to create a protective environment in the home, substituting nutritious foods for unhealthful ones and facilitating physical activities instead of sedentary pursuits. Other behaviors that may promote successful long-term weight management include good sleep hygiene, stress reduction, and mindfulness. Ultimately, the obesity epidemic can be attributed to changes in the social environment that hinder healthful lifestyle habits, and prevention will require a comprehensive public health strategy.

Preferences for type 2 diabetes health states among adolescents with or at risk of type 2 diabetes mellitus

OBJECTIVE

We evaluated how adolescents with or at risk of type 2 diabetes (T2DM) and their parent/guardians (parents) value health states associated with T2DM.

METHODS

We interviewed overweight/obese [Body Mass Index (BMI) ≥ 85th percentile], 12-18-yr old adolescents with T2DM, prediabetes, or insulin resistance (IR) and a parent. The standard gamble (SG) method elicited preferences (utilities) for seven hypothetical T2DM health states reported on a scale from 0 (dead) to 1 (perfect health). Adolescent's current health was evaluated with the SG and Health Utilities Index (HUI).

RESULTS

There were 70 adolescents and 69 parents. Adolescents were 67.1% female and 15.5 ± 2.2 yr old; 30% had T2DM, 30% prediabetes, and 40% IR. Almost half (48.6%) had a BMI > 99th percentile. Parents (83% mothers) were 45.1 ± 7.3 yr old and 75% had at least some college/technical school education. Adolescents and parents rated T2DM with no complications treated with diet as most desirable [median (IQR); adolescent 0.72 (0.54, 0.98); parent 1.0 (0.88, 1.0)] and end-stage renal disease as least desirable [adolescent 0.51 (0.31, 0.70); parent 0.80 (0.65, 0.94)]. However, adolescents' utilities were significantly lower (p ≤ 0.001) than parents for all health states assessed. Adolescents' assessments of their current health with the SG and HUI were not correlated.

CONCLUSIONS

Adolescents with or at risk of T2DM rated treatments and sequelae of diabetes as significantly worse than their parents. These adolescent utilities should be considered in the evaluation of treatment strategies for youth with T2DM. Family-based programs for T2DM must also be prepared to address conflicting preferences in order to promote shared decision-making.

Joint association of glycemic load and alcohol intake with type 2 diabetes incidence in women

BACKGROUND

Little is known about the joint association between glycemic index (GI), glycemic load (GL), and alcohol intake with type 2 diabetes (T2D).

OBJECTIVE

The objective of this study was to examine whether alcohol intake alters the associations between carbohydrate quality (GI) or quality and quantity (GL) and T2D incidence in women.

DESIGN

Participants from the Nurses' Health Study who were free of T2D, cardiovascular disease, or cancer (n = 81,827) at baseline in 1980 were followed for 26 y. Cumulative averages of GI, GL, total carbohydrates, and alcohol intake were calculated every 2-4 y from validated food-frequency questionnaires. Cox proportional hazard models were used to adjust for covariates.

RESULTS

We documented 6950 cases of T2D during follow-up. After adjustment for lifestyle and dietary factors, the positive association between GL and T2D risk was attenuated in subjects with higher alcohol intakes. RRs that compared the top and bottom quintiles of GL were 1.29 (95% CI: 1.11, 1.49; P-trend < 0.001) in women with alcohol intakes of 0 to <5 g/d, 1.34 (95% CI: 0.93, 1.92; P-trend = 0.05) in women with alcohol intakes of 5 to <15 g/d, and 0.99 (95% CI: 0.60, 1.65; P-trend = 0.82) in women with alcohol intakes ≥15 g/d (P-interaction = 0.02). However, a higher intake of alcohol did not modify the positive association between GI and T2D (P-interaction = 0.76).

CONCLUSION

Our findings suggest that a higher alcohol intake (≥15 g/d) attenuates the positive association between GL and T2D incidence.

Continuous glucose monitoring to assess the ecologic validity of dietary glycemic index and glycemic load

BACKGROUND

The circumstances under which the glycemic index (GI) and glycemic load (GL) are derived do not reflect real-world eating behavior. Thus, the ecologic validity of these constructs is incompletely known.

OBJECTIVE

This study examined the relation of dietary intake to glycemic response when foods are consumed under free-living conditions.

DESIGN

Participants were 26 overweight or obese adults with type 2 diabetes who participated in a randomized trial of lifestyle modification. The current study includes baseline data, before initiation of the intervention. Participants wore a continuous glucose monitor and simultaneously kept a food diary for 3 d. The dietary variables included GI, GL, and intakes of energy, fat, protein, carbohydrate, sugars, and fiber. The glycemic response variables included AUC, mean and SD of continuous glucose monitoring (CGM) values, percentage of CGM values in euglycemic and hyperglycemic ranges, and mean amplitude of glycemic excursions. Relations between daily dietary intake and glycemic outcomes were examined.

RESULTS

Data were available from 41 d of monitoring. Partial correlations, controlled for energy intake, indicated that GI or GL was significantly associated with each glycemic response outcome. In multivariate analyses, dietary GI accounted for 10% to 18% of the variance in each glycemic variable, independent of energy and carbohydrate intakes (P < 0.01).

CONCLUSIONS

The data support the ecologic validity of the GI and GL constructs in free-living obese adults with type 2 diabetes. GI was the strongest and most consistent independent predictor of glycemic stability and variability.