Tea And Bone Health: Findings From Human Studies, Potential Mechanisms, And Identification Of Knowledge Gaps by Leslie A. Nash, Wendy E. Ward

The population of the developed world is aging. With this aging population, strategies for prevention rather than treatment of chronic disease, such as osteoporosis, are essential for preserving quality of life and reducing health care costs. Tea is the second most consumed beverage in the world and is a rich source of flavonoids that may benefit bone health. There is strong evidence from human studies that habitual tea consumption is positively associated with higher BMD at multiple skeletal sites, while the association with fracture risk is less clear. Fracture studies demonstrate a reduction or no difference in fragility fracture with tea consumption. There are key questions that need to be answered in future studies to clarify if higher consumption of tea not only supports a healthy BMD, but also reduces the risk of fragility fracture. And if the latter relationship is shown to exist, studies to elucidate mechanisms can be designed and executed. This review discusses findings from epidemiological studies as well as potential mechanisms by which flavonoids in tea may mediate an effect, and identifies key knowledge gaps in this research area.

Fluoride content in Pan masala, chewing tobacco, betel nuts (supari), toothpastes and tooth-powder items used and consumed in rural and urban parts of Rampur district, Uttar Pradesh by Rajesh Kumar, S.S.Yadav

Levels of fluoride content in pan masala, chewing tobacco, betel nuts, toothpastes and tooth-powder were estimated in the rural and urban areas of Rampur district (Uttar Pradesh). These items are, generally, ignored while calculating the total dietary intake of fluoride. An effort was also made to quantify, on the basis of available studies, the probable human ingestion of fluoride through these substances. Increased leaching of fluoride from some of these substances has been observed in acidic conditions in the present study. The results can be extrapolated to acidic conditions of human stomach. The significant amount of fluoride ingested through these items is equivalent to additional sources of fluoride.

HUMAN EXPOSURE ASSESSMENT OF FLUORIDE FROM TEA (CAMELLIA SINENSIS L.) WITH SPECIFIC REFERENCE TO HUMAN BIOACCESSIBILITY STUDIES by Laura Chan

This study aims to determine the concentrations of fluoride in UK tea products andtheir infusions. This is related to the uptake and distribution of fluoride within teaplants Camellia sinensis (L.). Human oral bioaccessibility of fluoride from theconsumption of tea infusions was estimated, using an in vitro approach. The possiblehealth significance from fluoride exposure is discussed.Fluoride in tea products and the distribution within the tea plant was determinedusing a method, involving alkali fused digestion with ion chromatography and aconductivity detector for the instrumentation. For the aqueous infusions and thesupernatants in the bioaccessibility experiments, ion selective electrode with avoltmeter was adopted.Mean fluoride concentrations in tea products and their infusions varied significantly(p<0.001; n=3) and were related to the type of tea product and the retail cost. Thehigher priced teas, such as Darjeeling, Assam and Oolong, had lower fluorideconcentrations. The lower priced supermarket Economy ranged teas were significantlyhigher (p<0.05) in fluoride and exhibited concentrations similar to Chinese Brick tea,which is prepared using mature tea leaves. The higher quality products are preparedby selecting the finest tips of tea (buds), whereas an Economy products use coarserharvesting techniques to include mature leaves in the product.Fluoride affinity and tolerance of C. sinensis was assessed by a series of fluoride dosingexperiments, ranging from 0 to 200 mg. Following fluoride dosing, a rapid uptake andaccumulation occurred throughout the tea plants, resulting in partial necrosis ofrandom leaves. Despite the necrosis, the plants tolerated the fluoride and continuedto increase in height, although at a significantly slower rate (p<0.05) compared to thecontrol plants. Accumulation of fluoride was observed to be mostly in the matureleaves followed by younger buds, then the roots. This relates to the part of the plantivused to produce the tea types, with mature leaves for Economy products and the budsfor the finer teas.The in vitro bioaccessibility assessment of fluoride estimated that over 91.4% offluoride from a tea infusion is available in the human gastric compartment, with 92.1%in the gastro-intestinal compartment. The addition of milk reduced fluoride absorptionin the gastric and gastro-intestinal compartments to 73.8 and 83.1%, respectively,possibly reacting to form calcium fluoride. Despite the percentage bioaccessibility, theconcentration of fluoride available for absorption in the human gut was dependentupon choice of tea product. Based on an adult male, the findings suggest thatconsuming a litre of Economy tea can fulfil or exceed (75 to 120%) the recommendeddietary reference intake (DRI) of fluoride at 4 mg a day, but only partially fulfil (25 to40%) when consuming a more expensive Pure blend such as Assam.With regards to health, tea consumption is a source of fluoride in the diet and is highlyavailable for absorption in the human gut. Tea alone can fulfil an adult fluoride DRI,but is dependent upon choice of tea product. Excess fluoride in the diet can lead todetrimental health effects such as fluorosis of the teeth and skeletal fluorosis andconsuming economy branded tea can lead to a higher exposure.

Quantification of Fluoride in Food by Microwave Acid Digestion and Fluoride Ion-Selective Electrode by René A. Rocha, Dayana Rojas, Marıá Jesuś Clemente, Antonio Ruiz, Vicenta Devesa, and Dinoraz Veĺez

To quantify fluoride in food it is necessary to extract the fluoride from the matrix. Dry ashing (alkali fusion) and facilitated diffusion are the methods most commonly used, but their application requires lengthy treatments. The present study proposes the use of a microwave oven and 7 mol/L nitric acid for simple, rapid digestion of foods for fluoride analysis. The analyte is subsequently quantified by fluoride ion-selective electrode. The various steps of the method were optimized and an inhouse validation was performed. The limit of quantification (0.130 mg/kg), trueness (92%), recovery (84−101%), and precision (1−8%) were determined. These analytical characteristics are satisfactory and show the suitability of the method for analysis of fluoride in foods of various kinds. The method’s ease of application and the use of equipment normally found in food analysis laboratories may help to further increase research on fluoride concentrations in foods consumed by the population.

Link : https://www.researchgate.net/publication/257837234_Quantification_of_Fluoride_in_Food_by_Microwave_Acid_Digestion_and_Fluoride_Ion-Selective_Electrode

The fluoride content of select brewed and microwave-brewed black teas in the United States by Pamela Ruth Pehrsson , Kristine Y.Patterson, Charles R.Perry

Fluoride (F) in take is recognized to be important for dental health.Tea leaves are known Faccumulators and brewed tea as well as the water used for brewing may contribute significantly to individual intake. The USDA’s Nutrient Data Laboratory determined the F content of brewed and microwaved teasusing geographically matched tap water samples.Two brands of top-selling regular and one of decaffeinated tea bags were purchased in 36 locations and brewed either by steeping in boiled water or with microwave heating followed by steeping. The mean F content for caffeinated regular brewed tea was 373 49 mg/100 g(n = 63)and for decaffeinated tea was270 46 mg/100 g(n = 34).The overall mean for F in microwaved regular tea was lower than regular brew (364 40 mg/100 gvs.322 30 mg/100 g(n = 36)). In all cases, prepared tea using water from the Mid west had the highest F-values.The mean Fcontent of the brewed  teas was 3–4 times higher than the national mean of the tap water, analyzed separately (71 33 mg/ 100 g). These data are the first nationally representative F-values for brewed teas, and will provide valuable information to the dental and medical research communities in assessment of fluoride intake and impacton dental health.

Link : https://www.ars.usda.gov/SP2UserFiles/Place/80400525/Articles/JFCA_TeaFluoride.pdf

Fluoride in drinking water, brick tea infusion and human urine in two counties in Inner Mongolia, China by Hai-rong Li , Qing-bin Liub,Wu-yiWanga, Lin-sheng Yanga, Yong-hua Li , Fu-jian Fenga, Xiao-yu Zhaoa, Kun Houc, GeWang

https://www.researchgate.net/publication/244989314_Fluoride_in_drinking_water_brick_tea_infusion_and_human_urine_in_two_counties_in_Inner_Mongolia_China

The objective of this studywas to detect the fluoride level in the drinkingwater and the urine of habitantsaged 16–55 years living in Inner Mongolia China. Furthermore, fluoride concentration of the brick teainfusion samples which were drunk by Mongolia herdsmen in everyday life living in SumuErga village ofEjin Horo Banner, Inner Mongolia Chinawas also determined. A total of 117 participants (61 female and 56male) were recruited from two counties for a cross-sectional study on health effects of chronic fluorideexposure from drinking water and drinking brick tea infusion. The fluoride concentration in drinkingwater, urine and brick tea infusionsampleswere determined using fluoride ion selective electrodemethodobtained fromthe Ministry of Health of the People’s Republic of China. The average fluoride concentrationin drinkingwater sampleswas 0.32±0.01 mg/L at AretengXire town of Ejin Horo Banner, 0.70±0.19 mg/Lat SumuErga village of Ejin Horo Banner, and 2.68±1.15 mg/L at ZhalaiNuoer district of Manzhouli city. Theaverage fluoride concentration in brick tea infusion samples which collected from Mongolia herdsmen atSumuErga village of Ejin Horo Bannerwas 1.81±1.09 mg/L. The average urinary fluoride concentration atAretengXire town of Ejin Horo Banner was 0.59±0.48 mg/L, at SumuErga village of Ejin Horo Banner was1.45±0.93 mg/L and at ZhalaiNuoer district of Manzhouli city was 3.06±1.53 mg/L. The higher fluoridelevels in the urine of participants may be associated to higher fluoride in drinking water at ZhalaiNuoerof Manzhouli city. However, drinking brick tea infusions with higher fluoride may be the cause of thehigher fluoride contents in the Mongolia herdsmen’s urine.

Aluminium And Fluoride Contents Of Tea, With Emphasis On Brick Tea And Their Health Implications by M.H. Wong , K.F. Fung, H.P. Carr

Tea plant takes up a large quantity of aluminium (Al) and fluoride (F) from acidic soils. It has been known that fluorosis can be developed for people who consume a large quantity of tea made from brick tea, a low quality tea consisting mainly of old tea leaves in China. In addition, it has been claimed that Alzheimer’s disease (AD) is linked with the Al content in the human brain. Therefore, the high Al content in tea, especially brick tea is also a concern. This article reviews the basis background on tea including classification, growth conditions, types of tea leaves and their production, and processing of tea. Special emphasis is made on the transfer of Al and F from soil to tea plant and then to tea liquor. Health implications of drinking a large quantity of tea liquor especially those made from brick tea are discussed. Recommendations are suggested to reduce the uptake of these two elements by tea plant, and lower their contents in tea products.

Link :https://www.researchgate.net/publication/10971164_Aluminium_and_fluoride_contents_of_tea_with_emphasis_on_brick_tea_and_their_health_implications

Standard Methods for the Examination of Water and Wastewater

The analytical methods included in this part make use of classical wet chemical techniques
and their automated variations and such modern instrumental techniques as ion chromatography.
Methods that measure various forms of chlorine, nitrogen, and phosphorus are presented. The
procedures are intended for use in the assessment and control of receiving water quality, the
treatment and supply of potable water, and the measurement of operation and process efficiency
in wastewater treatment. The methods also are appropriate and applicable in evaluation of
environmental water-quality concerns. The introduction to each procedure contains reference to
special field sampling conditions, appropriate sample containers, proper procedures for sampling
and storage, and the applicability of the method.

Fluoride Bioavailability -- Nutritional And Clinical Aspects By Florian L. Cerklewski

Dietary fluoride obtained from food and water is efficiently absorbed from both the stomach and small intestine without regulation. A variety of dietary factors have been identified that either decrease or increase fluoride absorption and utilization. About half of absorbed fluoride is quickly taken-up by developing bone and teeth, and the remainder is excreted in the urine. The amount of fluoride excreted in the urine increases as bone growth slows. Nearly all of total body fluoride, which is second among the trace elements only to iron, is found in the skeleton. Although fluoride's unique role in mineralization provides the basis for its recognition as a beneficial trace element for dental health of humans, a more subtle role of fluoride in the mineralization of bone is also likely to exist. As with other essential trace elements, fluoride's action is biphasic in nature in that toxicity (fluorosis) can occur. Therapeutic effects of fluoride in the treatment of osteoporosis continue to be studied, and recent developments in this area point to a mitogenic role of fluoride in osteoblast cell proliferation. Recognition of fluoride essentiality for human health, rather than just being classified as beneficial, is likely to be forthcoming especially if reduction of a chronic disease is added to the criteria that establish a recommended dietary allowance.