Iodine Deficiency, Maternal Hypothyroxinemia and Endocrine Disrupters Affecting Fetal Brain Development: A Scoping Review.

This scoping review critically discusses the publications of the last 30 years on the impact of mild to moderate iodine deficiency and the additional impact of endocrine disrupters during pregnancy on embryonal/fetal brain development. An asymptomatic mild to moderate iodine deficiency and/or isolated maternal hypothyroxinemia might affect the development of the embryonal/fetal brain. There is sufficient evidence underlining the importance of an adequate iodine supply for all women of childbearing age in order to prevent negative mental and social consequences for their children. An additional threat to the thyroid hormone system is the ubiquitous exposure to endocrine disrupters, which might exacerbate the effects of iodine deficiency in pregnant women on the neurocognitive development of their offspring. Ensuring adequate iodine intake is therefore essential not only for healthy fetal and neonatal development in general, but it might also extenuate the effects of endocrine disruptors. Individual iodine supplementation of women of childbearing age living in areas with mild to moderate iodine deficiency is mandatory as long as worldwide universal salt iodization does not guarantee an adequate iodine supply. There is an urgent need for detailed strategies to identify and reduce exposure to endocrine disrupters according to the "precautional principle".

Codex recommendations on the scientific basis of health claims.

BACKGROUND: Within the framework of Codex Alimentarius, attempts are being made at international level to establish guidelines for use of nutrition and health claims. An important issue that has to be addressed is the process of scientific substantiating of claims on foods. OBJECTIVE: To provide an insight into the current step procedure of the proposed draft recommendations on the scientific basis of health claims. These Codex recommendations are intended to facilitate governments' own evaluation of health claims made by the industry. METHODS: Review of comments of governments, observers and non-governmental organizations (NGOs) and relevant references to the proposed draft recommendations of the last sessions of the Codex Committee on Nutrition and Food for Special Dietary Uses (CCNFSDU). A literature search was performed using the PubMed database. RESULTS/CONCLUSIONS: Several proposed draft recommendations on the scientific substantiation of health claims have been considered and amended by the CCNFSDU in recent years but the work is not yet complete. The current work draws on the work of FUFOSE and PASSCLAIM and also on that of WHO and FDA. Given the important role of Codex in food safety, the draft recommendations emphasize circumstances where additional evaluation of safety or nutritional safety needs to be considered. High quality human intervention studies are the prime evidence needed to substantiate claims but there is recognition that, in some cases, only observational studies may be available. Animal and in vitro studies will also be evaluated as part of the totality of the evidence. It has been suggested that the recommendations should include re-evaluation of claims after a certain time period, or if new evidence calls into question the scientific validity underpinning the claims. Setting out a common approach for the substantiation of health claims is an important step in the use of health claims around the world. There is a need to reflect emerging as well as consensus science. The substantiating evidence should be proportionate to the claim. Further progress in the elaboration of this relevant Codex text is needed to reach consensus.

Efficacy of isoflavones in relieving vasomotor menopausal symptoms - A systematic review.

This review assessed the efficacy of isoflavone supplements to reduce vasomotor symptoms in menopausal women by reviewing all published randomized controlled trials. Systematic literature searches were carried out in 70 databases. Randomized and placebo controlled studies were included if they investigated the treatment of isoflavone supplements derived from soy or red clover on vasomotor symptoms in peri- or postmenopausal women for at least 12 wks. Data were analyzed concerning outcome and methodological quality of the study. Twenty-three trials met the inclusion criteria, thereof 17 investigated soy isoflavones and 6 red clover isoflavones. Without exception, selected trials examining the effect of red clover isoflavones were already assessed in several meta-analyses and were therefore excluded from this evaluation. As the soy isoflavone studies were very heterogeneous concerning interventions and outcome measures, meta-analysis could not be performed and trials were systematically assessed in a structured approach. Included soy isoflavone studies had numerous quality deficiencies and did not consistently show a reduction of flushes after treatment with soy isoflavones. Therefore, there is no conclusive evidence, but only some indication of a benefit of soy isoflavones on hot flush frequency or severity.

Bioactive compounds: definition and assessment of activity.

Biomarkers and their role in evaluating efficacy and safety were the topic of the 23rd Hohenheim Consensus Meeting at the University of Hohenheim in Stuttgart. Scientists who had published and reviewed scientific and regulatory papers on the topic were invited, among them basic researchers, toxicologists, clinicians, and nutritionists. The participants were presented with 11 questions (in bold font), which were discussed and answered (in italic font) at the workshop, with the aim of summarizing the current state of knowledge on the subject. The explicatory text accompanying the short answers was produced and agreed on after the conference and was backed up by corresponding references.

Bioactive compounds: safety and efficacy.

The efficacy and safety of bioactive compounds depend on a few known and unknown parameters. What is a physiologic dose and how can that dose be defined in cases of bioactive compounds with a poor knowledge of supply and distribution? What safety sets are needed? How can individual aspects such as polymorphisms or differences in absorption be considered? A group of experts tried to answer these and related questions during the 23rd Hohenheim Consensus Meeting at the University of Hohenheim in Stuttgart.

Quantification of iodine supply: representative data on intake and urinary excretion of iodine from the German population in 1996.

BACKGROUND/METHODS: In Germany, iodine deficiency is common. In a representative group of 2,500 Germans (age >13 years), using a specially designed food questionnaire, the iodine intake was calculated. In addition, iodine and creatinine concentrations in spot urine samples were determined in three groups with a possibly increased risk of iodine deficiency (769 conscripts, 886 pairs of mothers and newborns) or future hyperthyroidism (574 adults, age range 50-70 years) from 26 representative regions. In four groups of controls (young and older male and female adults; n = 91), 24-hour urine iodine and creatinine were measured in six diurnal fractions to calculate group- and period-specific factors for the estimation of the 24-hour iodine excretion from data of iodine/creatinine ratio and time of micturition in spot urine samples. RESULTS: The mean calculated iodine intake (excretion) was 119 microg/day for the group of Germans above 13 years; it was 119 microg/day (125 microg/day) for adults aged 50-70 years, 137 microg/day (125 microg/day) for conscripts, and 162 microg/day for breast-feeding mothers. The median iodine concentration (iodine/creatinine ratio) was 9.4 microg/dl (83 microg/g) in 566 adults aged 50-70 years, 8.3 microg/dl (57 microg/g) in 772 conscripts. and 5.6 microg/dl (156 microg/g) in 739 breast-fed newborns. CONCLUSIONS: Compared to older data, the iodine intake in Germany has increased. In 1996, the meticulously quantified average deficit was about 30% of the recommended iodine intake.

PASSCLAIM - Synthesis and review of existing processes.

Several approaches to the use of health claims on foods have been made around the world, and the common theme is that any health claim will require scientific validation and substantiation. There is also broad consensus that any regulatory framework should protect the consumer, promote fair trade and encourage innovation in the food industry.This paper is based on a critical evaluation of existing international approaches to the scientific substantiation of health claims, with a view to identifying common new ideas, definitions, best practice and a methodology to underpin current and future developments. There is a clear need to have uniform understanding, terminology and description of types of nutrition and health claims. Two broad categories were defined: Nutrition Claims, i. e. what the product contains, and Health Claims, i. e. relating to health, well-being and/or performance, including well-established nutrient function claims, enhanced function claims and disease risk reduction claims. Such health claims relate to what the food or food components does or do. The categories of health claims are closely and progressively related and are, in practice, part of a continuum. Provision is also made for "generic" or well-established, generally accepted claims and for "innovative" or "product-specific" claims. Special attention was paid to reflect the health-promoting properties of a food or food component in such a way as to facilitate the making of risk reduction claims outside the medical scope of the term prevention. The paper sets out basic principles and guidelines for communication of health claims and principles of nutritional safety. The main body of the work examines the process for the assessment of scientific support for health claims on food and emphasises an evidence-based approach consisting of: Identification of all relevant studies exploring the collection of evidence, data searches, the nature of the scientific evidence, sources of scientific data (including human intervention studies, human observational studies, animal studies and in vitro studies, and the use of biomarkers in human studies. Evaluation of the quality of individual studies to ensure good experimental design and interpretation. Interpretation of the totality of evidence to apply scientific judgement to interpret the weight of evidence as a whole. Assessment of significant scientific agreement on a case-by-case basis to agree within the relevant scientific community that an association between a food or a food component and a health benefit is valid. Annexes include an international comparison of regulatory approaches to health claims, suggestions for the documentation and presentation of evidence, and a procedure for reviewing the evidence.