A collaborative group of international scientists, academics and medical practitioners have banded together without any funding to publish two major research studies addressing shortcomings in how public health policy decisions are made in Ireland and New Zealand. The New Zealand study, published on 21st June in the Journal of Environmental and Public Health follows an earlier Irish study published last year in the International Journal of Environmental Research and Public Health.
Both studies led by Irish scientist Declan Waugh, in collaboration with Dr. Hardy Limeback (Canada), Dr. William Potter (USA) and Dr Mike Godfrey of New Zealand address fluoride intake from tea and the associations between fluoride intake and chronic morbidity, including chronic pain, arthritic disease and osteoporosis. The New Zealand study, measured the fluoride content in 18 types of black tea products available in New Zealand, while the Irish Study tested 53 types of black tea for sale in the Republic of Ireland. In both studies, the daily intake of fluoride from tea consumption was determined and its contribution to dietary fluoride exposure assessed.
Speaking about the significance of both studies, lead author Mr. Waugh said: “In countries with water fluoridation, such as Ireland and New Zealand, it is imperative that fluoride intake from other sources is determined in order prevent the risk of chronic fluoride intoxication. Ireland and New Zealand are among the highest consumers of tea internationally, yet the contribution of tea to fluoride intake was never acknowledged before commenced of water fluoridation in the 1960s in either country.” Mr Waugh added: “Both these studies provide proof that the fluoride intake from tea is substantial and significantly higher than previously estimated by Public Health Authorities.”
Speaking about the health effects of chronic fluoride intake from tea, co-author Dr Mike Godfrey explained: “It is important to be aware that among adults musculoskeletal and chronic arthritic joint pain are the main long-term effects of overexposure to fluoride. In New Zealand, arthritis is the leading cause of disability costing the state almost € 2 billion annually.” (over $3 billion NZ dollars).
Dr Potter, Professor of Chemistry and Biochemistry added: “while our New Zealand study shows an association between fluoride intake and chronic pain disorders, it is important to note that our previous study, which measured fluoride levels in tea sold in Ireland, published last year in the peer reviewed IJERPH, found significantly higher fluoride levels than present in New Zealand teas. Moreover, tea consumption in Ireland is much higher than NZ and the cost of chronic pain disorders in Ireland exceed €5 billion annually. The findings of these studies suggest that both populations are chronically exposed to fluoride and that water fluoridation is further contributing to the burden of chronic pain disorders in either country.”
Dr. Limeback, Professor Emeritus and former member of the US National Academies Research Council Scientific Committee that investigated the health effects of fluoride added: “when calculating fluoride exposure, one must allow for cumulative exposures from all sources including tea, water, food, medications, toothpaste and occupational exposures, which can be high in certain industries or occupations. Our study shows that in countries with a history of tea drinking, fluoridation of drinking water further contributes to chronic exposure, thus increasing the risk of chronic pain disorders among the general population.” Ultimately, the authors of the studies conclude that there is a considerable gap in knowledge and in recognizing and identifying key risk factors that influence policy making decisions surrounding water fluoridation. Given the exposure of the populations to fluoride in tea, public health authorities must take steps to reduce the total body burden of fluoride in the population.
The NZ study is available here: https://www.hindawi.com/journals/jeph/2017/5120504/
The Irish study is available here: http://www.mdpi.com/1660-4601/13/3/259