Public health nutrition and genetics: implications for nutrition policy and promotion

Micronutrient-gene interactions related to inflammatory/immune response and antioxidant activity in ageing and inflammation. A systematic review

Recent longitudinal studies in dietary daily intake in human centenarians have shown that a satisfactory content of some micronutrients within the cells maintain several immune functions, a low grade of inflammation and preserve antioxidant activity. Micronutrients (zinc, copper, selenium) play a pivotal role in maintaining and reinforcing the performances of the immune and antioxidant systems as well as in affecting the complex network of the genes (nutrigenomic) with anti- and pro-inflammatory tasks. Genes of pro- and anti-inflammatory cytokines and some key regulators of trace elements homeostasis, such as Metallothioneins (MT), are involved in the susceptibility to major geriatric disease/disorders. Moreover, the genetic inter-individual variability may affect the nutrients' absorption (nutrigenetic) with altered effects on inflammatory/immune response and antioxidant activity. The interaction between genetic factors and micronutrients (nutrigenomic and nutrigenetic approaches) may influence ageing and longevity because the micronutrients may become also toxic. This review reports the micronutrient-gene interactions in ageing and their impact on the healthy state with a focus on the method of protein-metal speciation analysis. The association between micronutrient-gene interactions and the protein-metal speciation analysis can give a complete picture for a personalized nutrient supplementation or chelation in order to reach healthy ageing and longevity.

The challenges for molecular nutrition research 1: linking genotype to healthy nutrition

Nutrition science finds itself at a major crossroad. On the one hand we can continue the current path, which has resulted in some substantial advances, but also many conflicting messages which impair the trust of the general population, especially those who are motivated to improve their health through diet. The other road is uncharted and is being built over the many exciting new developments in life sciences. This new era of nutrition recognizes the complex relation between the health of the individual, its genome, and the life-long dietary exposure, and has lead to the realisation that nutrition is essentially a gene-environment interaction science. This review on the relation between genotype, diet and health is the first of a series dealing with the major challenges in molecular nutrition, analyzing the foundations of nutrition research. With the unravelling of the human genome and the linking of its variability to a multitude of phenotypes from "healthy" to an enormously complex range of predispositions, the dietary modulation of these propensities has become an area of active research. Classical genetic approaches applied so far in medical genetics have steered away from incorporating dietary effects in their models and paradoxically, most genetic studies analyzing diet-associated phenotypes and diseases simply ignore diet. Yet, a modest but increasing number of studies are accounting for diet as a modulator of genetic associations. These range from observational cohorts to intervention studies with prospectively selected genotypes. New statistical and bioinformatics approaches are becoming available to aid in design and evaluation of these studies. This review discusses the various approaches used and provides concrete recommendations for future research.

The role of innovation and technology in meeting individual nutritional needs

Few Americans meet the recommendations of the Dietary Guidelines for Americans and many do not know how to apply food and nutrition information to develop a personal approach to preventing diet/lifestyle-related diseases. In a time of rapid technologic advancement and rewards for innovation, a critical opportunity in food and nutrition science exists for improving health and reducing disease risk. The National Center for Food Safety and Technology (NCFST) recently established the Health Promoting Foods research platform to support the availability of safe food by using emerging technologies for improving food quality and consumer choice. A workshop convened with leading regulators and nutrition, genetic, medical, toxicological, behavioral, and consumer scientists to: discuss challenges facing personalized nutrition and health, develop strategies to overcome challenges using innovations in food and information technology, and define and prioritize a short- and long-term research agenda for the research platform. The workshop included presentations and in-depth discussions on the state of the science in genomics, behavior, food, and information technology. Workshop participants identified gaps, intersections, and new opportunities for delivering individualized food-based solutions that would be more accessible, affordable, and convenient. The research agenda, which was developed within a framework of providing information and guidance to the food and associated industries, supporting the process for health-related claims, building consumer confidence in data and food-health information, and providing a pathway for implementation of the US Dietary Guidelines for Americans and other public policies, reflects the commitment of the community, government, food industry, health organizations, and academia to improving health.

Nutritional genomics and dietetic professional practice

Nutrigenomics is concerned with the role of nutrients in gene expression, and nutrigenetics is the study of how genetic variants or polymorphisms (mutations) can affect responses to nutrients; nutritional genomics is the umbrella term. Nutritional genomics can be expected to revolutionize the way dietitians and other health professionals identify people with chronic diseases and treat those diseases. Understanding the science of nutritional genomics is important to dietitians and other health professionals because major scientific advancements such as this usually have a significant impact on ethics, policy, and practice. Blood lipid profiles are one area in which nutritional genomics has quickly advanced knowledge. New knowledge is available on blood lipid profiles and associated conditions, such as obesity and type 2 diabetes. New technology has also had an impact on policy and practice issues, and ethics is an important issue to consider.

Zinc-gene interaction related to inflammatory/immune response in ageing

The pivotal role played by zinc-gene interaction in affecting some relevant cytokines (IL-6 and TNF-alpha) and heat shock proteins (HSP70-2) in ageing, successful ageing (nonagenarians) and the most common age-related diseases, such as atherosclerosis and infections, is now recognized. The polymorphisms of genes codifying proteins related to the inflammation are predictive on one hand in longevity, on the other hand they are associated with atherosclerosis or severe infections. Since the health life-span has a strong genetic component, which in turn also affected by nutritional factors like zinc, the association of these polymorphisms with innate immune response, zinc ion bioavailability and Metallothioneins (MT) homeostasis is an useful tool to unravel the role played by zinc-gene interactions in longevity, especially due to the inability of MT in zinc release in ageing and chronic inflammation. In ageing, this last fact leads to depressed innate immune response for host defence. In contrast, in very old age the inflammation is lower with subsequent more zinc ion bioavailability, less MT gene expression and satisfactory innate immunity. Therefore, the zinc-gene (IL-6, TNF-alpha, Hsp70-2) interactions, via MT homeostasis, are crucial to achieve successful ageing.

Integrating anticipated nutrigenomics bioscience applications with ethical aspects

Nutrigenomics is a subspecialty of nutrition science which aims to understand how gene-diet interactions influence individuals' response to food, disease susceptibility, and population health. Yet ethical enquiry into this field is being outpaced by nutrigenomics bioscience. The ethical issues surrounding nutrigenomics face the challenges of a rapidly evolving field which bring forward the additional dimension of crossdisciplinary integrative research between social and biomedical sciences. This article outlines the emerging nutrigenomics definitions and concepts and analyzes the existing ethics literature concerning personalized nutrition and presents "points to consider" over ethical issues regarding future nutrigenomics applications. The interest in nutrigenomics coincides with a shift in emphasis in medicine and biosciences toward prevention of future disease susceptibilities rather than treatment of already established disease. Hence, unique ethical issues emerge concerning the extent to which nutrigenomics can alter our relation to food, boundaries between health and disease, and the folklore of medical practice. Nutrigenomics can result in new social values, norms, and responsibilities for both individuals and societies. Nutrigenomics is not only another new application of "-omics" technologies in the context of gene-diet interactions. Nutrigenomics may fundamentally change the way we perceive human illness while shifting the focus and broadening the scope of health interventions from patients to healthy individuals. In resource- and time-limited healthcare settings, this creates unique ethical dilemmas and distributive justice issues. Ethical aspects of nutrigenomics applications should be addressed proactively, as this new science develops and increasingly coalesces with other applications of genomics in medicine and public health.

From farm to pharma: public health challenges of nutrigenomics

Nutrigenomics is speculated to be the next big dimension of genomic sciences geared toward improving public and personal health through nutritional and dietary interventions. This article traces how public health nutrition has been used as an agenda both in agriculture genomics and now in biomedicine. The centrality and importance of food in health and well-being is well recognized and, with the developments in genomics, it has also been used as a tool for public health-related policies and commercialization. This perspective discusses nutrigenomics from four public health perspectives; novel foods and the public health agenda; the epidemic of lifestyle-related diseases, such as obesity, diabetes and cardiovascular diseases; commercialization; and conceptual issues. Several ethical and governance issues in applying nutrigenomics to public health and the implications for public policy will also be considered.

Continuing Education Needs of Registered Dietitians Regarding Nutrigenomics

The purpose of this study was to assess continuing education needs for registered dietitians regarding application of the science of nutritional genomics in clinical settings. A cross-sectional survey was mailed to a random national sample of 2,500 registered dietitians with a 40% response rate (n=995). The survey assessed knowledge; attitudes related to benefits and barriers to application; perceptions of consumer motivators and barriers; attitudes regarding ethical, legal, and social issues; and preferences for continuing education. Differences were determined according to year of registration using nonparametric Kruskal-Wallis tests. Survey respondents had little previous exposure to nutrigenomics, had not applied nutrigenomics in their practice in the past year, and were not confident in their ability to apply nutrigenomics in a clinical setting, but were interested in learning more about its application. Few differences existed in attitudes about benefits and barriers to application of nutrigenomics by year of registration. The most favored learning activity for continuing education was seminars/workshops. The most important content areas for continuing education were foundational knowledge, application, and communication to the lay public. Continuing education should focus on these content areas to allow application based on the supporting science and ways to effectively communicate the information to consumers.