Effect of Incorporating Genetic Testing Results into Nutrition Counseling and Care on Health Outcomes: An Evidence Analysis Center Systematic Review—Part II

In recent years, literature examining implementation of nutritional genomics into clinical practice has increased, including publication of several randomized controlled trials (RCTs). This systematic review addressed the following question: In children and adults, what is the effect of incorporating results of genetic testing into nutrition counseling and care compared with an alternative intervention or control group, on nutrition-related health outcomes? A literature search of MEDLINE, Embase, PsycINFO, CINAHL, and other databases was conducted for peer-reviewed RCTs published from January 2008 until December 2018. An international workgroup consisting of registered dietitian nutritionists, systematic review methodologists, and evidence analysts screened and reviewed articles, summarized data, conducted meta-analyses, and graded conclusion statements. The second in a two-part series, this article specifically summarizes evidence from RCTs that examined health outcomes (ie, quality of life, disease incidence and prevention of disease progression, or mortality), intermediate health outcomes (ie, anthropometric measures, body composition, or relevant laboratory measures routinely collected in practice), and adverse events as reported by study authors. Analysis of 11 articles from nine RCTs resulted in 16 graded conclusion statements. Among participants with nonalcoholic fatty liver disease, a diet tailored to genotype resulted in a greater reduction of percent body fat compared with a customary diet for nonalcoholic fatty liver disease. However, meta-analyses for the outcomes of total cholesterol, low-density lipoprotein cholesterol, body mass index, and weight yielded null results. Heterogeneity between studies and low certainty of evidence precluded development of strong conclusions about the incorporation of genetic information into nutrition practice. Although there are still relatively few well-designed RCTs to inform integration of genetic information into the Nutrition Care Process, the field of nutritional genomics is evolving rapidly, and gaps in the literature identified by this systematic review can inform future studies.     

Effect of Incorporating Genetic Testing Results into Nutrition Counseling and Care on Dietary Intake: An Evidence Analysis Center Systematic Review—Part I

Consumer interest in personalized nutrition based on nutrigenetic testing is growing. Recently, multiple, randomized controlled trials have sought to understand whether incorporating genetic information into dietary counseling alters dietary outcomes. The objective of this systematic review was to examine how incorporating genetic information into nutrition counseling and care, compared to an alternative intervention or control group, impacts dietary outcomes. This is the first of a 2-part systematic review series. Part II reports anthropometric, biochemical, and disease-specific outcomes. Peer-reviewed randomized controlled trials were identified through a systematic literature search of multiple databases, screened for eligibility, and critically reviewed and synthesized. Conclusion statements were graded to determine quality of evidence for each dietary outcome reported. Reported outcomes include intake of total energy and macronutrients, micronutrients, foods, food groups, food components (added sugar, caffeine, and alcohol), and composite diet scores. Ten articles representing 8 unique randomized controlled trials met inclusion criteria. Of 15 conclusion statements (evidence grades: Weak to Moderate), 13 concluded there was no significant effect of incorporating genetic information into nutrition counseling/care on dietary outcomes. Limited data suggested that carriers of higher-risk gene variants were more likely than carriers of low-risk gene variants to significantly reduce intake of sodium and alcohol in response to nutrition counseling that incorporated genetic results. Included studies differed in quality, selected genetic variants, timing and intensity of intervention, sample size, dietary assessment tools, and population characteristics. Therefore, strong conclusions could not be drawn. Collaboration between the Academy of Nutrition and Dietetics and professional nutrigenetic societies would likely prove valuable in prioritizing which genetic variants and targeted nutrition messages have the most potential to alter dietary outcomes in a given patient subpopulation and, thus, should be the targets of future research.     

Impact of Garden-Based Youth Nutrition Intervention Programs: A Review

Garden-based nutrition-education programs for youth are gaining in popularity and are viewed by many as a promising strategy for increasing preferences and improving dietary intake of fruits and vegetables. This review examines the scientific literature on garden-based youth nutrition intervention programs and the impact on nutrition-related outcomes. Studies published between 1990 and 2007 were identified through a library search of databases and an examination of reference lists of relevant publications. Studies were included if they involved children and adolescents in the United States and examined the impact of garden-based nutrition education on fruit and/or vegetable intake, willingness to taste fruits and vegetables, preferences for fruits and vegetables, or other nutrition-related outcomes. Only articles published in peer-reviewed journals in English were included in the review. Eleven studies were reviewed. Five studies took place on school grounds and were integrated into the school curriculum, three studies were conducted as part of an afterschool program, and three studies were conducted within the community. Studies included youth ranging in age from 5 to 15 years. Findings from this review suggest that garden-based nutrition intervention programs may have the potential to promote increased fruit and vegetable intake among youth and increased willingness to taste fruits and vegetables among younger children; however, empirical evidence in this area is relatively scant. Therefore, there is a need for well-designed, evidenced-based, peer-reviewed studies to determine program effectiveness and impact. Suggestions for future research directions, including intervention planning, study design, evaluation, and sustainability are provided.     

State of the Evidence Regarding Behavior Change Theories and Strategies in Nutrition Counseling to Facilitate Health and Food Behavior Change

Behavior change theories and models, validated within the field of dietetics, offer systematic explanations for nutrition-related behavior change. They are integral to the nutrition care process, guiding nutrition assessment, intervention, and outcome evaluation. The American Dietetic Association Evidence Analysis Library Nutrition Counseling Workgroup conducted a systematic review of peer-reviewed literature related to behavior change theories and strategies used in nutrition counseling. Two hundred fourteen articles were reviewed between July 2007 and March 2008, and 87 studies met the inclusion criteria. The workgroup systematically evaluated these articles and formulated conclusion statements and grades based upon the available evidence. Strong evidence exists to support the use of a combination of behavioral theory and cognitive behavioral theory, the foundation for cognitive behavioral therapy (CBT), in facilitating modification of targeted dietary habits, weight, and cardiovascular and diabetes risk factors. Evidence is particularly strong in patients with type 2 diabetes receiving intensive, intermediate-duration (6 to 12 months) CBT, and long-term (>12 months duration) CBT targeting prevention or delay in onset of type 2 diabetes and hypertension. Few studies have assessed the application of the transtheoretical model on nutrition-related behavior change. Little research was available documenting the effectiveness of nutrition counseling utilizing social cognitive theory. Motivational interviewing was shown to be a highly effective counseling strategy, particularly when combined with CBT. Strong evidence substantiates the effectiveness of self-monitoring and meal replacements and/or structured meal plans. Compelling evidence exists to demonstrate that financial reward strategies are not effective. Goal setting, problem solving, and social support are effective strategies, but additional research is needed in more diverse populations. Routine documentation and evaluation of the effectiveness of behavior change theories and models applied to nutrition care interventions are recommended.     

Implementation of the Nutrition Care Process and International Dietetics and Nutrition Terminology in a Single-Center Hemodialysis Unit: Comparing Paper vs Electronic Records

There is little doubt surrounding the benefits of the Nutrition Care Process and International Dietetics and Nutrition Terminology (IDNT) to dietetics practice; however, evidence to support the most efficient method of incorporating these into practice is lacking. The main objective of our study was to compare the efficiency and effectiveness of an electronic and a manual paper-based system for capturing the Nutrition Care Process and IDNT in a single in-center hemodialysis unit. A cohort of 56 adult patients receiving maintenance hemodialysis were followed for 12 months. During the first 6 months, patients received the usual standard care, with documentation via a manual paper-based system. During the following 6-month period (Months 7 to 12), nutrition care was documented by an electronic system. Workload efficiency, number of IDNT codes used related to nutrition-related diagnoses, interventions, monitoring and evaluation using IDNT, nutritional status using the scored Patient-Generated Subjective Global Assessment Tool of Quality of Life were the main outcome measures. Compared with paper-based documentation of nutrition care, our study demonstrated that an electronic system improved the efficiency of total time spent by the dietitian by 13 minutes per consultation. There were also a greater number of nutrition-related diagnoses resolved using the electronic system compared with the paper-based documentation (P<0.001). In conclusion, the implementation of an electronic system compared with a paper-based system in a population receiving hemodialysis resulted in significant improvements in the efficiency of nutrition care and effectiveness related to patient outcomes.     

Nutrition Care in Bariatric Surgery: An Academy Evidence Analysis Center Systematic Review

Obesity continues to be a major public health crisis, both nationally and globally. Metabolic and bariatric surgery has been proven to be a safe and effective treatment for this multifactorial chronic disease. However, inconsistent and varied results in bariatric nutrition literature have prevented the implementation of standardized guidelines. The purpose of this Evidence Analysis Library systematic review is to provide an evidence-based summary of nutrition-related practices in bariatric surgery. The systematic review methodology of the Academy of Nutrition and Dietetics was applied. A total of 27 research studies were included, analyzed, and assessed for risk of bias by trained evidence analysts. The literature included in the systematic review was published from 2003 to 2015. Evaluation of the literature resulted in the development of five graded conclusion statements. Limited research demonstrates that registered dietitian nutritionists play a role in improving weight loss outcomes after bariatric surgery; further research is needed to understand the role of registered dietitian nutritionists in changing behaviors after bariatric surgery. Bariatric surgery results in significant reductions in resting metabolic rate and postoperative energy intake. There is no significant relationship between macronutrient distribution and postoperative weight loss. The graded conclusion statements provide registered dietitian nutritionists who practice in the field of bariatric nutrition with more insight and evidence that can guide and support their recommendations.     

Strengthening Nutrition Education and Behavior Research for Academicians and Practitioners

Nutrition education and behavior research is essential for translating scientific nutrition-related evidence into actionable strategies at the individual, family, community, and policy levels. To enhance the impact of nutrition educators and researchers’ efforts, there is a need for continued and directed support to sustain the rigor of research. It is the perspective of this paper that the field of nutrition education and behavior research address its inherent complexities to meet the diverse investigative strategies used by academicians as well as practitioners. Such strategies could ensure the role of nutrition education and behavior in ongoing nationwide efforts to address emerging and novel nutrition research.     

Comparison of a Web-Based vs In-Person Nutrition Education Program for Low-Income Adults

As access to computers and the Internet by the low-income population is increasing and the “digital divide” is slowly diminishing, other methods of delivering nutrition information to this audience are evolving. This randomized, block equivalence trial sought to determine whether web-based nutrition education could result in equivalent nutrition-related behavior outcomes when compared with traditional in-person nutrition education in low-income adults. A convenience sample of low-income adults (n=123) was randomized to receive in-person education (n=66) or web-based education (n=57) in a community setting within 14 counties of Indiana from April through December 2010. The web-based group received three nutrition education lessons (eg, fruits and vegetables, Nutrition Facts label reading, and whole grains) designed to replicate lessons received by the in-person group. Lessons were developed using Kolb's Learning Styles and Experiential Learning Model. Self-reported nutrition-related behaviors were assessed using a previously validated survey for low-income adults. Most nutrition-related behavior outcomes (eg, fruit, vegetable, whole-grain intake, Nutrition Facts label use, breakfast, and meal-planning frequency) improved significantly (P<0.05) from pre to post within both groups, meaning that each intervention was effective. When these nutrition-related behavior improvements were compared between groups, the changes were statistically equivalent (P>0.05), except for one question about use of the Nutrition Facts label. Therefore, web-based nutrition education can lead to favorable and equivalent nutrition-related changes when compared with in-person delivery. Most (83%) web-based participants also reported willingness to use the website again. Future application of web-based interventions for low-income populations could broaden delivery reach, increase frequency and length of contacts, and possibly decrease costs.     

A Scoping Literature Review of the Relation between Nutrition and ASD Symptoms in Children

Autism spectrum disorder (ASD) is characterized by impairments in social interaction, communication skills, and repetitive and restrictive behaviors and interests. Even though there is a biological basis for an effect of specific nutrition factors on ASD symptoms and there is scientific literature available on this relationship, whether nutrition factors could play a role in ASD treatment is unclear. The goal of the current literature review was to summarize the available scientific literature on the relation between nutrition and autism spectrum disorder (ASD) symptoms in childhood, and to formulate practical dietary guidelines. A comprehensive search strategy including terms for ASD, nutrition factors (therapeutic diets, dietary patterns, specific food products, fatty acids and micronutrients) and childhood was developed and executed in six literature databases (Cinahl, Cochrane, Ovid Embase, PsycInfo, PubMed and Web of Science). Data from meta-analyses, systematic reviews and original studies were qualitatively summarized. A total of 5 meta-analyses, 29 systematic reviews and 27 original studies were retrieved that focused on therapeutic diets, specific food products, fatty acids and micronutrients and ASD symptoms during childhood. Results of the available studies were sparse and inconclusive, and hence, no firm conclusions could be drawn. There is currently insufficient evidence for a relation between nutrition and ASD symptoms in childhood, making it impossible to provide practical nutrition guidelines; more methodological sound research is needed.     

Dietary Macronutrient Distribution and Nutrition Outcomes in Persons with Cystic Fibrosis: An Evidence Analysis Center Systematic Review

Cystic fibrosis (CF) increases risk for undernutrition and malabsorption. Individuals with CF traditionally have been counseled to consume a high-fat diet. However, a new era of CF care has increased lifespan and decreased symptoms in many individuals with CF, necessitating a re-examination of the high-fat CF legacy diet. A literature search was conducted of Medline (Ovid), Embase, and CINAHL (EBSCO) databases to identify articles published from January 2002 to May 2018 in the English language examining the relationships between dietary macronutrient distribution and nutrition outcomes in individuals with CF. Articles were screened, risk of bias was assessed, data were synthesized narratively, and each outcome was graded for certainty of evidence. The databases search retrieved 2,519 articles, and 7 cross-sectional articles were included in the final narrative analysis. Three studies examined pediatric participants and 4 examined adults. None of the included studies reported on outcomes of mortality or quality of life. Very low certainty evidence described no apparent relationship between dietary macronutrient distribution and lung function, anthropometric measures, or lipid profile in individuals with CF. The current systematic review demonstrates wide ranges in the dietary macronutrient intakes of individuals with CF with little to no demonstrable relationship between macronutrient distribution and nutrition-related outcomes. No evidence is presented to substantiate an outcomes-related benefit to a higher fat-diet except in the context of achieving higher energy intakes in a lesser volume of food.     

Science-Based Regulatory and Policy Considerations in Nutrition

Scientific evidence is necessary for the development of effective and enforceable regulations and government policy. To use scientific information appropriately, a systematic approach is needed for review and evaluation of the evidence. Federal agencies in the United States have developed useful approaches for such a review and evaluation to develop nutrition labeling, including health claims, and for updating of the Dietary Guidelines for Americans. The WHO is using a systematic evaluation process to update its recommendations on diet and health. The results of such reviews also highlight research needs to address relevant gaps in our knowledge.     

Nutrition Interventions in Pediatric Patients with Type 1 Diabetes: An Evidence Analysis Center Scoping Review

The objective of this scoping review was to identify and characterize studies examining the effect of nutrition management interventions and effectiveness of medical nutrition therapy to improve nutrition-related outcomes in children and adolescents with type 1 diabetes. An in-depth electronic search was conducted by a medical librarian in six databases: Medline, Embase, Cochrane Central Register of Controlled Trials, PsycINFO, The Cumulative Index to Nursing and Allied Health Literature, and Web of Science Core Collection. The literature search resulted in 5,122 records, and five records were identified through hand search. Of these 5,127 records, 22 articles and eight systematic reviews met our inclusion criteria. An equal number of the studies were experimental (ie, randomized or nonrandomized controlled trials, or noncontrolled trials) (n = 11) and observational (cohort, case-control, and cross-sectional) (n = 11) with the remaining studies being systematic reviews/meta-analyses (n = 8). Most of these studies were conducted in United States or Europe. Based on this scoping review, the majority of studies focus on either carbohydrate counting or evaluation of dietary intake patterns with little emphasis on tailored patient education/counseling services specifically designed to meet a young child’s or his/her family's individual needs. Indeed, only four studies in this scoping review used dietary counseling and/or medical nutrition therapy. As such, there remains a significant gap in the literature as it relates to the efficacy and long-term management implications of tailored nutrition interventions in young children with type 1 diabetes.     

Nutrition Competencies in Health Professionals’ Education and Training: A New Paradigm

Most health care professionals are not adequately trained to address diet and nutrition-related issues with their patients, thus missing important opportunities to ameliorate chronic diseases and improve outcomes in acute illness. In this symposium, the speakers reviewed the status of nutrition education for health care professionals in the United States, United Kingdom, and Australia. Nutrition education is not required for educating and training physicians in many countries. Nutrition education for the spectrum of health care professionals is uncoordinated, which runs contrary to the current theme of interprofessional education. The central role of competencies in guiding medical education was emphasized and the urgent need to establish competencies in nutrition-related patient care was presented. The importance of additional strategies to improve nutrition education of health care professionals was highlighted. Public health legislation such as the Patient Protection and Affordable Care Act recognizes the role of nutrition, however, to capitalize on this increasing momentum, health care professionals must be trained to deliver needed services. Thus, there is a pressing need to garner support from stakeholders to achieve this goal. Promoting a research agenda that provides outcome-based evidence on individual and public health levels is needed to improve and sustain effective interprofessional nutrition education.     

Review of the Nutritional Implications of Farmers' Markets and Community Gardens: A Call for Evaluation and Research Efforts

The development and promotion of farmers' markets and community gardens is growing in popularity as a strategy to increase community-wide fruit and vegetable consumption. Despite large numbers of farmers' markets and community gardens in the United States, as well as widespread enthusiasm for their use as a health promotion tool, little is known about their influcence on dietary intake. This review examines the current scientific literature on the implications of farmers' market programs and community gardens on nutrition-related outcomes in adults. Studies published between January 1980 and January 2009 were identified via PubMed and Agricola database searches and by examining reference lists from relevant studies. Studies were included in this review if they took place in the United States and qualitatively or quantitatively examined nutrition-related outcomes, including dietary intake; attitudes and beliefs regarding buying, preparing, or eating fruits and vegetables; and behaviors and perceptions related to obtaining produce from a farmers' market or community garden. Studies focusing on garden-based youth programs were excluded. In total, 16 studies were identified for inclusion in this review. Seven studies focused on the impact of farmers' market nutrition programs for Special Supplemental Nutrition Program for Women, Infants, and Children participants, five focused on the influence of farmers' market programs for seniors, and four focused on community gardens. Findings from this review reveal that few well-designed research studies (eg, those incorporating control groups) utilizing valid and reliable dietary assessment methods to evaluate the influence of farmers' markets and community gardens on nutrition-related outcomes have been completed. Recommendations for future research on the dietary influences of farmers' markets and community gardens are provided.     

Nutrition and neurodevelopment in children: focus on NUTRIMENTHE project

There is growing evidence that early nutrition affects later cognitive performance. The idea that the diet of mothers, infants, and children could affect later mental performance has major implications for public health practice and policy development and for our understanding of human biology as well as for food product development, economic progress, and future wealth creation. To date, however, much of the evidence is from animal, retrospective studies and short-term nutritional intervention studies in humans. The positive effect of micronutrients on health, especially of pregnant women eating well to maximise their child’s cognitive and behavioural outcomes, is commonly acknowledged. The current evidence of an association between gestational nutrition and brain development in healthy children is more credible for folate, n-3 fatty acids, and iron. Recent findings highlight the fact that single-nutrient supplementation is less adequate than supplementation with more complex formulae. However, the optimal content of micronutrient supplementation and whether there is a long-term impact on child’s neurodevelopment needs to be investigated further. Moreover, it is also evident that future studies should take into account genetic heterogeneity when evaluating nutritional effects and also nutritional recommendations. The objective of the present review is to provide a background and update on the current knowledge linking nutrition to cognition and behaviour in children, and to show how the large collaborative European Project NUTRIMENTHE is working towards this aim.     

Does tailoring make a difference? A systematic review of the long-term effectiveness of tailored nutrition education for adults

Tailoring individualizes information to the receiver and provides a potential strategy for improving dietary intakes. The present systematic review summarizes evidence for the long-term ( ≥ 6 months) effectiveness of tailored nutrition education for adults and includes priority population groups. Key electronic databases and relevant bibliographies were searched for trials measuring the following outcomes: nutrition-related health behaviors (e.g., dietary intake and food purchases) and anthropometric measures. Data synthesis was comprised of meta-analysis (for 15 trials including all population groups) and narrative review (for five trials of priority population groups). Overall, the quality of the studies was moderate to good. Tailored nutrition education was found to be a promising strategy for improving the diets of adults (including those in priority population groups) over the long term. However, future studies should ensure adequate reporting of research design and methods and reduce the chances of false-positive findings by using more objective measures of diet, clearly identifying the primary study outcome, and concentrating on outcomes most relevant to nutrition-related disease.     

Nutrition beyond drugs and devices: a review of the approaches to enhance the capacity of nutrition care provision by general practitioners

The prevention and management of chronic disease is a key priority for primary care services. Nutrition-related care is an integral feature of several best practice guidelines for management of chronic disease in the general practice setting. This paper critically reviews the international literature to enhance the nutrition knowledge, skills and overall capacity of GPs to provide nutrition care using examples from nutrition in medical education, continuing medical education, GP-centred and practice-setting approaches. The medical nutrition education approach provides an opportunity for linear translation between desired nutrition competencies and curriculum learning objectives, while that of continuing medical education allows for tailored nutrition education to increase nutrition competencies once a learning need is identified. The GP-centred approach focuses on the determinants of nutrition care provision by GPs as strategies for enhancing nutrition care delivery, whereas the practice setting approach aims to increase the nutrition-related exposure to patients through avenues independent of the GP. In the Australian and New Zealand context, the potential appropriateness of these approaches requires judicious consideration, as it is unlikely that one approach will comprehensively address this topic. Ongoing multifaceted evaluation of each approach is needed to ensure enhancement of GPs' capacity to provide nutrition care by increasing nutrition knowledge and skills, and improving patient health outcomes.