Effects of nutrition education on weight gain prevention: a randomized controlled trial

Behavioral Counseling Interventions to Promote a Healthy Diet and Physical Activity for Cardiovascular Disease Prevention in Adults Without Known Cardiovascular Disease Risk Factors: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Unhealthful dietary patterns, low levels of physical activity, and high sedentary time increase the risk of cardiovascular disease.

OBJECTIVE

To synthesize the evidence on benefits and harms of behavioral counseling interventions to promote a healthy diet and physical activity in adults without known cardiovascular disease (CVD) risk factors to inform a US Preventive Services Task Force recommendation.

DATA SOURCES

MEDLINE, PsycINFO, and the Cochrane Central Register of Controlled Trials through February 2021, with ongoing surveillance through February 2022.

STUDY SELECTION

Randomized clinical trials (RCTs) of behavioral counseling interventions targeting improved diet, increased physical activity, or decreased sedentary time among adults without known elevated blood pressure, elevated lipid levels, or impaired fasting glucose.

DATA EXTRACTION AND SYNTHESIS

Independent data abstraction and study quality rating and random effects meta-analysis.

MAIN OUTCOMES AND MEASURES

CVD events, CVD risk factors, diet and physical activity measures, and harms.

RESULTS

One-hundred thirteen RCTs were included (N = 129 993). Three RCTs reported CVD-related outcomes: 1 study (n = 47 179) found no significant differences between groups on any CVD outcome at up to 13.4 years of follow-up; a combined analysis of the other 2 RCTs (n = 1203) found a statistically significant association of the intervention with nonfatal CVD events (hazard ratio, 0.27 [95% CI, 0.08 to 0.88]) and fatal CVD events (hazard ratio, 0.31 [95% CI, 0.11 to 0.93]) at 4 years. Diet and physical activity behavioral counseling interventions were associated with small, statistically significant reductions in continuous measures of blood pressure (systolic mean difference, -0.8 [95% CI, -1.3 to -0.3]; 23 RCTs [n = 57 079]; diastolic mean difference, -0.4 [95% CI, -0.8 to -0.0]; 24 RCTs [n = 57 148]), low-density lipoprotein cholesterol level (mean difference, 2.2 mg/dL [95% CI, -3.8 to -0.6]; 15 RCTs [n = 6350]), adiposity-related outcomes (body mass index mean difference, -0.3 [95% CI, -0.5 to -0.1]; 27 RCTs [n = 59 239]), dietary outcomes, and physical activity at 6 months to 1.5 years of follow-up vs control conditions. There was no evidence of greater harm among intervention vs control groups.

CONCLUSIONS AND RELEVANCE

Healthy diet and physical activity behavioral counseling interventions for persons without a known risk of CVD were associated with small but statistically significant benefits across a variety of important intermediate health outcomes and small to moderate effects on dietary and physical activity behaviors. There was limited evidence regarding the long-term health outcomes or harmful effects of these interventions.

Preventing weight gain in adults: A systematic review and meta-analysis of randomized controlled trials

Weight gain prevention is a global public health priority to address escalating adiposity in adults. This review evaluates the efficacy of weight gain prevention trials targeting adults aged 18-50 years and adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. Trials of any duration from inception to May 2020 that evaluated a weight gain prevention intervention (using either prescriptive diet, prescriptive physical activity, prescriptive diet, and/or physical activity or non-prescriptive lifestyle) and included weight or body mass index (weight [kg]/height [m² ]) were eligible. Twenty-nine trials across 34 publications (participants n = 37,407) were included. Intervention resulted in less weight gain compared with controls (-1.15 kg [95% CI -1.50, -0.80 kg] p < 0.001). Subgroup analysis demonstrated greater effectiveness with prescriptive (-1.60 kg [95% CI -2.00, -1.19] p < 0.001) compared with non-prescriptive (-0.81 kg [95% CI 1.10, -0.53] p < 0.001) intervention types. Interventions had greatest impact in healthy weight (18.5-24.9 kg/m² ) (-0.82 kg [95% CI -1.5, -0.50] p < 0.001) or overweight (25.0-29.9 kg/m² ) (-1.48 kg [95% CI -1.85, -1.12] p < 0.001) compared with obese populations (≥30.0 kg/m² ) (-0.56 kg [95% CI -1.40, 0.27] p = 0.19). These findings demonstrate that lifestyle intervention prevents cumulative weight gain in non-obese adults, with future research required to inform cost-effectiveness and implementation feasibility.

The Relationship of Diet and Physical Activity with Weight Gain and Weight Gain Prevention in Women of Reproductive Age

Reproductive-age women often see increased weight gain, which carries an increased risk of long-term overweight and obesity and adverse maternal and child health outcomes. Supporting women to achieve optimal weight through lifestyle modification (diet and physical activity) is of critical importance to reduce weight gain across key reproductive life-stages (preconception, pregnancy and postpartum). This review comprehensively summarizes the current state of knowledge on the contribution of diet and physical activity to weight gain and weight gain prevention in reproductive-aged women. Suboptimal diets including a higher proportion of discretionary choices or energy intake from fats, added sugars, sweets or processed foods are associated with higher weight gain, whereas increased consumption of core foods including fruits, vegetables and whole grains and engaging in regular physical activity are associated with reduced weight gain in reproductive age women. Diet and physical activity contributing to excessive gestational weight gain are well documented. However, there is limited research assessing diet and physical activity components associated with weight gain during the preconception and postpartum period. This review highlights the need for further research to identify key dietary and physical activity components targeting the critical windows of reproductive life-stages in women to best guide interventions to prevent weight gain.

Applying RE-AIM to Evaluate the External Validity of Weight Gain Prevention Interventions in Young Adults: A Systematic Review

OBJECTIVES

The purpose of this review was to use RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) to assess the extent to which weight gain prevention studies targeting young adults reported on elements of external validity.

DESIGN

Systematic review.

ELIGIBILITY CRITERIA

Articles of interest included a lifestyle/behavioral intervention targeting weight gain prevention. Eligibility criteria included the following: study design of randomized controlled trials, quasi-randomized control trials, or natural experiments; average participant age between 18 and 35 years; study duration of at least 12 months; and published in English between January 2008 and May 2018. Studies had to report weight or body mass index as a measured outcome and were excluded if they were paired with smoking cessation programs, were conducted in specific groups (ie, pregnant women, breast cancer survivors), or were follow-ups to weight loss studies.

STUDY SELECTION

After removing duplicates, the search yielded 11426 articles. Titles and abstracts were screened by 1 reviewer; 144 articles were assessed in a full-text review by 2 reviewers. Discrepancies were resolved by consensus. Nine studies (13 articles) were included in the review.

MAIN OUTCOMES MEASURES

Reported elements of the RE-AIM framework.

RESULTS

A total of 9 studies met the selection criteria. All studies lacked full reporting on external validity elements. Of the total of 60 RE-AIM reporting criteria, 8 were reported by all 9 studies, 26 criteria were reported by fewer than 4 studies, and 22 criteria were not reported by any of the studies.

DISCUSSION

There remains inadequate reporting of elements of external validity and generalizability in weight gain prevention studies. This is a significant scientific constraint that limits the information required to disseminate and implement prevention of weight gain interventions for population impact. Standardized reporting may be needed to ensure results that demonstrate not only internal validity but also external validity and generalizability are needed to promote public health impact.

Weight Management Interventions for Adults With Overweight or Obesity: An Evidence Analysis Center Scoping Review

The objectives of this evidence scoping review were to identify and characterize studies investigating weight management interventions provided by a registered dietitian nutritionist or international equivalent (RDN) among adults with overweight or obesity. A medical librarian conducted an electronic literature search in 6 databases-MEDLINE (Ovid), Embase (Ovid), PyscINFO (Ovid), Cochrane CENTRAL (Ovid), Cochrane Database of Systematic Reviews (Ovid), and CINAHL (Ebsco). Except for narrative review, gray literature, and case study or report, all types of peer-reviewed articles published between January 2008 and April 26, 2019 were eligible. Two content advisors, who are experts in adult weight management, guided the process and reviewed the search plan and findings. The literature search resulted in 30,551 records with 16 additional records identified through other sources. A total of 29,756 records were excluded during the first round of screening due to duplication or irrelevancy. Of the 811 full-text articles that were screened, 139 met the criteria and were included. Approximately 51% and 43% of the studies were conducted in the community setting and in the United States or Canada, respectively. Over 97% of the studies were clinical or quasi-experimental trials. A total of 6 different intervention delivery modes were reported, which resulted in 22 combinations of the modes of delivery. RDNs delivered the weight management intervention (especially the nutrition component) in all studies, but some (61%) also involved an interdisciplinary team to deliver other components of the intervention. The average length of the intervention was about 10 months with a follow-up that ranged from 0 to 9 years. The commonly reported outcomes were anthropometrics, endocrine, and cardiovascular measures; dietary intake; and physical activity. Based on the scoping review, there were systematic reviews and evidence-based practice guidelines on weight management interventions but none of them met the a priori inclusion or exclusion criteria. Therefore, it would be beneficial to conduct a systematic review and develop an evidence-based practice guideline on adult weight management interventions provided by an RDN to guide practitioners and to evaluate their effects on health and nutrition-related outcomes.

Obesity: Assessment and prevention: Module 23.2 from Topic 23 "Nutrition in obesity"

Obesity is one the major health problems of today showing an increasing prevalence among most countries. It is associated with increased risk of several diseases. The importance of early life strategies in the prevention of obesity is well established, whereas, in general, breastfed infants tend to have a lower body mass index (BMI) than formula-fed infants. There seem to be a series of behavioral and hormonal mechanisms that explain this difference. Lifestyle plays a crucial role in the development of overweight and/or obesity and targeted lifestyle modifications have an important impact on preventing obesity. In particular, sedentary behavior (viewing television, playing video games, doing cognitive work, and listening to music) and reduced overall physical activity along with shorter sleep duration promote the overconsumption of dietary macronutrients leading to obesity; at the same time physical activity or exercise in a sufficient dose seems to better facilitate long-term maintenance of new lower body weight. There is enough discussion about a potential effect of nutrients on obesity. Nevertheless, the most the crucial parameter regarding weight loss and prevention of obesity is to achieve a negative energy balance. In regard to specific diet regimes, again energy balance rather that any specific macronutrients composition and/or favoring of low glycemic index products, seems to be have a stronger effect on maintenance of lower weight after 12 months. It has to be noted, that for specific sup groups, obesity or overweight might be showing some favorable trends in survival. In particular, "obesity paradox" (OP) refers to an overall prognosis that is no worse and may even be better in some groups than non-obese patients. The OP could be explained by the fact that current classifications of obesity based on BMI may place together, in the same category, subjects with very different clinical and biochemical characteristics.

Beverage intake during alternate-day fasting: Relationship to energy intake and body weight

BACKGROUND

Alternate-day fasting (ADF) involves a 'famine day' (25% energy intake) and a 'feast day' (ad libitum intake). This secondary analysis examined changes in beverage intake in relation to energy intake and body weight during 12 months of ADF versus daily calorie restriction (CR).

METHODS

Obese subjects (n = 100 enrolled, n = 69 completers) were randomized to one of three groups for 12 months: (a) ADF; (b) CR; or (c) control.

RESULTS

At baseline, intakes of diet soda, caffeinated beverages, sugar-sweetened soda, alcohol, juice, and milk were similar between groups. There were no statistically significant changes in the intake of these beverages by month 6 or 12 between ADF (feast or famine day), CR, or control groups. Beverage intake was not related to energy intake or body weight at month 6 or 12 in any group.

CONCLUSION

These pilot findings suggest that intermittent fasting does not impact beverage intake in a way that affects energy intake or body weight.

EFFECT OF DORSOMEDIAL HYPOTHALAMUS NEUROPEPTIDE Y KNOCKDOWN ON HEPATIC INSULIN SENSITIVITY

Objective

In this study we investigated the effect of dorsomedial hypothalamus (DMH) neuropeptide Y (NPY) knock-down on hepatic insulin sensitivity in high-fat (HF) diet-fed rats.

Methods

Forty-eight Sprague-Dawley rats were randomly assigned to receive bilateral DMH injections of adeno-associated virus AAVshNPY or AAVshCTL and then accessed to regular chow. Five weeks after viral injection, half rats in each group were given access to the HF diet. At 16 weeks, rat livers were collected. Insulin receptor substrate-1 (IRS-1) and phosphoinositide 3-kinase (PI3K) mRNA expression was measured by qRT-PCR. Blood glucose levels were measured by the oxidase method, serum insulin, triglyceride, and TC levels were measured by Elisa. Pathological changes in the liver were assessed by hematoxylin-eosin (HE) staining. AKT, p-AKT, and GSK-3 levels were measured by western blotting.

Results

Compared with AAVshCTL-injected rats, AAVshNPY-injected rats showed a significant decrease in blood glucose concentrations; serum insulin, triglyceride, and TC; HOMA-IR; and IRS-1 and PI3K mRNA levels (P<0.05). ISI, GSK-3, and p-AKT levels were significantly increased (P<0.05). HE staining showed that AAVshNPY-injected rats fed the HF diet had mild fatty degeneration.

Conclusion

These results suggest that DMH NPY knock-down improves hepatic insulin sensitivity in HF diet-fed rats by activating the hepatic PI3K/AKT insulin signalling pathway.

The effect of a weight gain prevention intervention on moderate-vigorous physical activity among black women: the Shape Program

BACKGROUND

Rates of physical inactivity are high among Black women living in the United States with overweight or obesity, especially those living in the rural South. This study was conducted to determine if an efficacious weight gain prevention intervention increased moderate-vigorous physical activity (MVPA).

METHODS

The Shape Program, a weight gain prevention intervention implemented in community health centers in rural North Carolina, was designed for socioeconomically disadvantaged Black women with overweight or obesity. MVPA was measured using accelerometers, and summarized into 1- and 10-min bouts. We employed analyses of covariance (ANCOVA) to assess the relationship between changes in MVPA over 12 months, calculated as a change score, and intervention assignment (intervention versus usual care).

RESULTS

Participants completing both baseline and 12-month accelerometer assessments (n = 121) had a mean age of 36.1 (SD = 5.43) years and a mean body mass index of 30.24 kg/m² (SD = 2.60). At baseline, 38% met the physical activity recommendation (150 min of MVPA/week) when assessed using 10-min bouts, and 76% met the recommendation when assessed using 1-min bouts. There were no significant differences in change in MVPA participation among participants randomized to the intervention from baseline to 12-months using 1-min bouts (adjusted intervention mean [95% CI]: 20.50 [-109.09 to 150.10] vs. adjusted usual care mean [95% CI]: -80.04 [-209.21 to 49.13], P = .29), or 10-min bouts (adjusted intervention mean [95% CI]: 7.39 [-83.57 to 98.35] vs. adjusted usual care mean [95% CI]: -17.26 [-107.93 to 73.40], P = .70).

CONCLUSIONS

Although prior research determined that the Shape intervention promoted weight gain prevention, MVPA did not increase significantly among intervention participants from baseline to 12 months. The classification of bouts had a marked effect on the prevalence estimates of those meeting physical activity recommendations. More research is needed to understand how to promote increased MVPA in weight gain prevention interventions.

TRIAL REGISTRATION

This study is registered at www.clinicaltrials.gov database (No. NCT00938535. Retrospectively Registered 7/10/2009).

Gender differences and access to a sports dietitian influence dietary habits of collegiate athletes

BACKGROUND

Limited research exists on the effect of a sports dietitian (SD) on athletes' dietary habits and nutrient periodization, which is the deliberate manipulation of macronutrient intake to match training goals. Further, the difference in dietary habits between men and women collegiate athletes has been understudied. A survey questionnaire examining dietary habits and practices was administered to athletes at two universities that employed a full time SD. Not all athletes used the SD as their primary source for nutritional guidance. The purposes were to examine the effect of a SD as a primary source of nutrition information, and the effect of gender on dietary habits in collegiate athletes.

METHODS

Three hundred eighty-three women (n = 240) and men (n = 143) student-athletes (mean ± SD: age = 19.7 ± 1.4 years) from 10 collegiate sports took a 15-min survey consisting of questions on dietary habits and practices. Topics queried included eating habits, breakfast habits, hydration habits, nutritional supplementation use, pre-workout nutrition, post-workout nutrition, nutrition during team trips, and nutrient timing. Data were sorted by the athlete's source of nutritional information (i.e., sport dietitian, other). Data analysis consisted of descriptive statistics and 2-way Pearson X2 analyses (p ≤ 0.10).

RESULTS

When a SD was indicated as the primary nutrition information source, athletes appeared to have a greater understanding of nutrient periodization (47.12 % vs. 32.85 %), were more likely to have school-provided boxed meals while on team trips (21.29 % vs. 6.77 %), and also less likely to consume fast food while on team trips (9.90 % vs. 19.55 %). Men athletes consumed fast food or restaurant meals more frequently, had higher weekly and more frequent alcohol intake during the competitive season. Women athletes were more likely to prepare meals, eat breakfast 7 days a week, and have school-provided boxed meals.

CONCLUSIONS

Positive effects on dietary habits were observed when a SD was the primary nutrition information source. Practitioners should be aware of the gender differences in alcohol intake, fast food consumption, and knowledge of nutrient periodization. Collegiate athletes and athletic staff members could benefit from SD access to safeguard against dietary habits detrimental to performance.