REVISED FLUORIDE NUTRIENT REFERENCE VALUES FOR INFANTS AND YOUNG CHILDREN IN AUSTRALIA AND NEW ZEALAND Summary The revised fluoride Nutrient Reference Values (NRVs) for the Adequate Intake (AI) and Upper Level of Intake (UL) for infants and young children were endorsed 1 by the Council of the National Health and Medical Research Council (NHMRC) and recommended to the Chief Executive Officer for issuing on 3 November 2016. This is an outcome of a review managed by the Australian Government Department of Health and the New Zealand Ministry of Health of the existing fluoride NRVs for Australia and New Zealand, published by the NHMRC in 2006 2. The scope of this review was limited to an AI and UL for infants and young children. Adequate Intake The AI 3 for fluoride for children aged 7 months to 8 years has been reaffirmed to be 0.05 milligrams per kilogram of bodyweight per day (mg/kg bw/day), an intake associated with appreciably reduced rates of tooth decay (dental caries). Updated bodyweight information resulted in changes to the AI values by age-group when presented as an amount of fluoride intake per day, when compared with the 2006 values (the new recommendations are detailed below). 2017 Recommendations for the Adequate Intake of Fluoride for Children 0-8 years (by age group) Age AI 0 6 months Not applicable 7 12 months 0.5 mg/day* 1-3 years 0.6 mg/day 4-8 years 1.1 mg/day It is recognised that infants 0-6 months are not necessarily exclusively breastfed, however an AI was not established for infants less than six months of age as a review of evidence for formula and breastfed infants found that a preventive effect of fluoride intake in this age group could not be established. This is in line with international recommendations. Therefore the 2006 AI for 0-6 months has been withdrawn and there is no AI for this age group. 1 The NHMRC Act 1992 gives the Chief Executive Officer, on the advice of the Council of NHMRC, the power to approve guidelines developed by an external body, in this case, the Australian Department of Health and New Zealand Ministry of Health, provided they meet NHMRC s guideline standards. 2 National Health and Medical Research Council, Australian Government Department of Health and Ageing, New Zealand Ministry of Health. Nutrient reference values for Australia and New Zealand including recommended dietary intakes. Canberra: Commonwealth of Australia; 2006. 3 The AI is defined as the average daily nutrient intake level based on observed or experimentally determined approximations or estimates of nutrient intake by a group (or groups) of apparently healthy people that are assumed to be adequate (NHMRC 2006). * Rounded to the first decimal place
The AIs for children and adolescents over 8 years of age, adults, pregnant and lactating women remain as per NHMRC s 2006 NRVs for Australia and New Zealand. Upper Level of Intake The UL 4 for fluoride for infants and children up to 8 years has been revised from 0.10 mg/kg bw/day to 0.20 mg/kg bw/day, based on evidence that at this level of intake the risk of an adverse effect, in this case severe dental fluorosis, is reduced to an acceptable level. Updated bodyweight information was used to present the UL as an amount of fluoride intake per day. Dental fluorosis affects the appearance of the teeth. It can range from faint white areas (very mild or mild fluorosis) to pitting and loss of the enamel surface of teeth (severe fluorosis). The dental fluorosis found in Australia and New Zealand is predominantly very mild or mild and does not affect the function of teeth. It is caused by an over mineralisation of teeth caused by high fluoride intake during tooth development (up to the age of 8 years). 2017 Recommendations for the Upper Level of Intake for Children 0-8 years (by age group) Age UL 0 6 months 1.2 mg/day 7 12 months 1.8 mg/day 1-3 years 2.4 mg/day 4-8 years 4.4 mg/day The ULs for children and adolescents over 8 years of age, adults, pregnant and lactating women remain as per NHMRC s 2006 NRVs for Australia and New Zealand. Bodyweight data used to determine AI and UL values by age-group New reference bodyweight data for Australian and New Zealand children aged 4-8 years 5 were used to determine new values for the AI and UL expressed in mg fluoride per day. The most recent US reference bodyweight data were used for infants and children aged 1-3 years 6 as no Australian and New Zealand data were available for these age groups. 4 The UL is the highest average daily nutrient intake level likely to pose no adverse health effects to almost all individuals in the general population. As intake increases above the UL, the potential risk of adverse effects increases (NHMRC 2006). The term average daily nutrient intake refers to the usual intake for a population typically derived from two or more days of records. 5 Australian Bureau of Statistics (ABS) 2014. Ideal bodyweights (calculated), Customised report, Commonwealth of Australia. 6 National Research Council (NRC) 2005. Dietary Reference Intakes for Energy, Carbohydrate, Fibre, Fat, Fatty Acids, Cholesterol, Protein and Amino Acids (Macronutrients), in Appendix B, the National Academies Press, Washington, DC
Application of Fluoride Nutrient Reference Values The recommendations for the revised AI and UL for fluoride have no implications for the current Drinking Water Guidelines in Australia and the current Drinking Water Standards for New Zealand or for recommendations on fluoride ingestion from toothpaste. The fluoride recommendations refer to habitual intake of fluoride and are used to assess fluoride intakes at a population level. They apply to the generally well population of children aged 7 months to 8 years (AI) and children aged 0 to 8 years (UL) and are not intended to be guidelines on dental/oral health or clinical practice guidelines used by dental and health professionals/practitioners treating individuals. The NRVs for fluoride are health based guidance values designed to be used as reference standards by dietitians and other health professionals/practitioners working in different settings when developing clinical practice guidelines, assessing dietary requirements of populations and as the basis for public health policy initiatives. They can provide a benchmark for activities that involve monitoring and assessing population fluoride intake and fluoride levels in the food supply. Public health professionals/practitioners and food legislators may use the NRVs to undertake dietary modelling, risk assessments and/or set food standards, including food labelling standards. The food industry may refer to the NRVs in relation to food formulation. Rationale for the Adequate Intake The purpose of the AI for infants and young children is to provide information on the level of intake that provides protection from inadequate intake, which in the case of fluoride results in increased risk of dental caries. Rationale for the withdrawal of an Adequate Intake for infants 0-6 months An AI has not been established for infants less than six months of age. The review of evidence did not find a preventive effect (reduction in dental caries) with fluoride intake in the first six months of life. This is in line with the view expressed by the Institute of Medicine (IOM) in 1997 7 and supported by the American Dental Association s Council on Scientific Affairs statement in 2011 that the preventive effect of fluoride in the first six months of life has not been established. Rationale for the Upper Level of Intake The purpose of the UL is to provide information on the upper level of intake above which the risk of an adverse effect increases, in the case of fluoride, severe dental fluorosis. The estimated UL for fluoride is 0.20 mg/kg bw/day for ch ildren aged 0 to 8 years. The UL is based on the 95th percentile of fluoride intake (representative of high consumers) and a theoretical water fluoridation level of drinking water of 1.9 mg fluoride/litre (beyond which severe enamel fluorosis is likely to appear). Beyond 8 years of age, when the enamel forms on permanent teeth, the ingestion of fluoride does not cause further developmental changes to teeth. 7 Food and Nutrition Board: Institute of Medicine. Dietary Reference Intakes for calcium, phosphorus, magnesium, vitamin D and fluoride. Washington DC: National Academy Press, 1997.
The estimate is higher than the 2006 UL for fluoride of 0.1 mg/kg bw/day which was based on the IOM 1997 report 8 and higher than the fluoride Reference Dose of 0.08 mg/kg bw/day established by the US Environmental Protection Agency (EPA) in 2010 9. The Fluoride Expert Working Group noted there was an inconsistency in the estimation of the UL in the IOM report and considered the EPA s use of the mean dietary fluoride intake, rather than a high percentile (95 th ) fluoride intake did not provide a robust basis to derive a UL for fluoride. For a full explanation of these differences see Section 5.5.3 of the 2017 fluoride NRV review report. Upper Level of Intake for infants 0-6 month The UL for the 0-6 month age range is primarily focused on fluoride intake among infant formula fed and infants who receive complementary foods before six months of age, as the review of evidence found that breast milk is low in fluoride and breastfed infants of this age are unlikely to exceed the UL. Implications of NRV revisions for infant formula composition The withdrawal of the AI for infants 0-6 months and changes to the UL for infants do not impact on infant formula composition. Infant formula sold in Australia and New Zealand contains very low amounts of fluoride (reported 0.07 mg fluoride/ kg 10 ). The Australia New Zealand Food Standards Code (the Code) does not prescribe a level for fluoride content, however, guidance is given in the Code for labelling infant formula products. If fluoride concentration is more than 17 µg/100 kj in powdered or concentrated product prior to reconstitution, or more than 0.15 mg/100 ml (1.5 mg fluoride /L) in ready to drink formula products a labelling statement on the package is required. This statement should indicate that consumption of the formula has the potential to cause dental fluorosis plus a statement recommending that the risk of dental fluorosis should be discussed with a medical practitioner or other health professional. Given the low levels of fluoride content of infant formula sold in Australia and New Zealand, labelling on fluoride content is unlikely to be required. Cooled boiled tap water is preferred for preparing infant formula, consistent with Infant Feeding Guidelines in Australia and New Zealand. Background information Fluoride Fluoride is widespread in nature and a normal part of the human body. It is particularly concentrated in teeth and bone and helps form tooth enamel. Fluoride is ingested from several sources including foods, beverages, fluoridated and unfluoridated water, fluoridated toothpastes and some dietary supplements. Both 8 Food and Nutrition Board: Institute of Medicine. Dietary Reference Intakes for calcium, phosphorus, magnesium, vitamin D and fluoride. Washington DC: National Academy Press, 1997. 9 Environmental Protection Agency 2010a.Fluoride: Dose-response analysis for non-cancer effects. Office of Water, Health and Ecological Criteria Division, Washington, DC.USA, EPA Doc. 820R10015. 10 Clifford H, Olszowy H, Young M, Hegart J, Cross M 2009. Fluoride content of powdered infant formula meets Australian Food Safety Standards, Aust NZ J Public Health; 33(6): 573 576.
inadequate and excessive fluoride intakes can affect dental health. Inadequate intakes are associated with increased tooth decay (dental caries) and excessive intakes with damage to tooth enamel (dental fluorosis). Australia and New Zealand have pursued public health policy to adjust fluoride intake at the population level with the aim of preventing dental caries without causing moderate or severe dental fluorosis with adverse effects. It is considered desirable to have a fluoride intake that is sufficient to prevent much dental caries (an AI) without exceeding intakes that are associated with severe dental fluorosis (a UL). Review of the 2006 Nutrient Reference Values In 2011, the Department of Health, in consultation with the New Zealand Ministry of Health commissioned a scoping study for undertaking a review of the 2006 NRVs. This resulted in the development of a Methodological Framework (the Framework) to guide nutrient reviews. In order to test the Framework, three priority nutrients; fluoride, sodium and iodine, were chosen to review. Fluoride was identified as a priority nutrient as recent estimates of dietary fluoride intake in Australia and New Zealand suggested that the fluoride intake of a substantial proportion of infants and young children exceeded the 2006 NRV for the UL. At the same time, there was no evidence of widespread occurrence of moderate or severe dental fluorosis, suggesting the UL needed to be reviewed. The review of fluoride NRVs was limited to the cohort of children up to eight years of age, as this is the period of time in which permanent teeth are formed and therefore the critical age group to consider for dental caries and fluorosis. This review was managed by the Australian Department of Health and the New Zealand Ministry of Health. NHMRC s guideline standards were followed to ensure the 2017 recommendations were developed to rigorous standards. The report of the revised fluoride NRVs for infants and children was released for public consultation from 30 October 2015 to 11 December 2015, and subjected to an independent methodological review and three independent expert reviews prior to approval from the Council of the NHMRC on 3 November 2016. Governance The review was funded by the Department of Health and the New Zealand Ministry of Health. A Steering Group comprising of representatives from each government organisation oversaw the funding and strategic decisions of the review. An Advisory Committee comprising members with a broad range of expertise including in micronutrients, toxicology, nutrition risk assessment, public health, end user needs, research, chronic disease and nutrition provided technical expert advice and acted as an independent moderator of the nutrient recommendations. The Fluoride Expert Working Group was primarily responsible for undertaking the review by examining the scientific evidence. The Working Group comprised of experts in the field of toxicology, nutrition, dentistry, population oral health and oral epidemiology. More information on the revised fluoride NRVs and the review process can be found at www.nhmrc.gov.au and www.nrv.gov.au
Referencing Document Reference National Health and Medical Research Council, Australian Government Department of Health and Ageing, New Zealand Ministry of Health. Nutrient reference values for Australia and New Zealand including recommended dietary intakes. Canberra: Commonwealth of Australia; 2006. Chapter Reference National Health and Medical Research Council, Australian Government Department of Health and Ageing, New Zealand Ministry of Health. Nutrient reference values for Australia and New Zealand including recommended dietary intakes: Fluoride (revised 2017). Canberra: Commonwealth of Australia; 2006.