Special article26th Hohenheim Consensus Conference, September 11, 2010 Scientific substantiation of health claims: Evidence-based nutrition
Introduction
An important objective of global regulatory legislation is to ensure that health claims on foods and food constituents can be properly justified and scientifically substantiated. Consumers should be able to make choices based on clear and accurate information and have confidence in the scientific and regulatory processes used to support health claims. Any framework must not only protect consumers from false and misleading claims but also satisfy the needs of industry to promote and innovate, to stimulate multidisciplinary research, and to reinvigorate efforts to process and preserve raw materials from agriculture, horticulture, fisheries, and aquaculture into a diverse range of foods and food supplements.
Global regulatory frameworks currently reflect the role of food and food constituents in maintaining and promoting human health and in decreasing the risk of disease. The purpose of this consensus conference was to consider recent developments and initiatives on the scientific substantiation of health claims and to pay particular attention to the following items.
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The assessment of the totality of the available data and the need for the development of a scientific framework for weighing the strength, consistency, biological plausibility, and coherence of the evidence.
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A critical examination of the application of the model for evidence-based medicine in nutrition science; evidence-based medicine is designed to evaluate the effects of drugs and not the unique properties, complex effects, and interactions of nutrients and bioactive substances.
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The need to address and define evidence-based nutrition, to embrace state-of-the-art nutrition science, and to stimulate future academic research.
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The identification and validation of relevant biomarkers that can predict potential benefits relating to maintenance or improvement of a function and those associated with decreased risk of disease.
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The determination of the strength of recommendations to reflect the available evidence and consensus among experts in a particular field to communicate truthful nutritional and health messages to the public.
The final decision on whether or not a claim should be allowed rests with the regulators and policy managers, taking into account the scientific assessments of the strength and coherence of the evidence and other societal and health policy considerations including the broader purposes of food labeling and claims to help and improve the public understanding of nutrition and to support strategies for public health promotion and improvement.
To discuss the requirements for the scientific substantiation of claims, the 26th Hohenheim Consensus Conference gathered the views of many academic experts in the field of nutritional research and asked these experts to address the various aspects of a claims substantiation process and the possibilities and limitations of the different approaches. The experts spent a day presenting and discussing their views and arrived at some consensus statements that can serve as guidance for bodies performing claims assessments in the framework of regulatory systems. This report addresses several general aspects and describes the current scientific status from the point of view of five case studies to illustrate specific relevant perspectives:
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Carotenoids and Vitamin A in relation to age-related macular degeneration (AMD).
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The quality of carbohydrates (as expressed by the glycemic index [GI]) in relation to health and well-being.
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Probiotics in relation to intestinal and immune functions.
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Micronutrient intake and maintenance of normal body functions.
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Food components with antioxidative properties and health benefits.
Section snippets
Assessing the totality of the available evidence for diet–health relations
This section discusses methodologies for assessing the validity of diet–health relations, with a particular focus on how to consider the totality of the available data, weigh the evidence, and address the strength, consistency, and biological plausibility of a particular diet and health relation. It also deals with requirements and processes to develop research methodologies to demonstrate beneficial effects in a healthy population.
Case studies
In this section several case studies were discussed to address under what conditions the totality of the current scientific data and supportive evidence from generally accepted sources and recognized scientific institutions could find more suitable alternatives to RCTs.
These case studies address the following diet–health relations:
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Carotenoids and vitamin A in relation to AMD.
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The quality of carbohydrates (as expressed by the GI) in relation to health and well-being.
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Probiotics in relation to
Role of various types of scientific data: clinical trials, meta-analysis, and observational and traditional evidence
One particular field of discussion is the value of the various sources of scientific data in support of a diet–health relation. This includes the advantages and limitations of sources including RCTs, meta-analysis, observational evidence, and traditional use in the process of assessing the evidence for diet–health relations. This section addresses these aspects of the claims assessment process.
The future of nutritional research
This session addresses whether claims relating to the maintenance of health would need to be assessed in a different way than claims that relate to the decrease of the development of a disease and what is the role of generally accepted scientific evidence in this respect.
Conclusion
All types and sources of data need to be considered in the weighing of the totality of the evidence, and the best and most logical resource to assess the evidence available in support of the biological plausibility and probability of the beneficial role of a nutrient or food component is by gathering the experts in the field and reaching conclusions in the form of a scientific consensus. This assures that the totality of the evidence is considered and that conclusions are reached in the best
Acknowledgments
The authors thank the European Responsible Nutrition Alliance for their financial support of this conference and publishing the report. The authors thank Jana Tinz for her assistance in publishing the report as supplement coordinator. They also thank Dr. Claudia Wicke for the organization of the consensus conference.
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This work was financially supported by the European Responsible Nutrition Alliance.