Dietary fluoride

Hunt CD, Stoecker BJ. 1996. Deliberations and evaluations of the approaches, endpoints, and paradigms for boron, chromium, and fluoride dietary recommendations. RDA Workshop New approaches, endpoints and paradigms for RDAs of mineral elements 2441S-S2451. 

Dabeka RW, McKenzie AD, Lacroix GMA. 1987. Dietary intakes of lead, cadmium, arsenic and fluoride by Canadian adults A 24-hour duplicate diet study. Food Addit Contam 4 89-102. 

Many other dietary factors have been reported to affect calcium bioavailability. Phytate, fiber, cellulose, uronic acids, sodium alginate, oxalate, fat (only in the presence of steatorrhea), and alcohol have been reported to decrease calcium bioavailability (15). Lactose and medium chain triglyceride increase it (15). FTuoride also affects calcium retention primarily by stimulating bone formation thereby decreasing calcium excretion (33-38). The effects of fluoride on calcium utilization have been variable (34,38,39). 

Whereas much attention has been paid to the effects of dietary fluoride on the skeleton of domestic and experimental animals and man (T8), knowledge about the accumulation of fluoride in soft tissues such as heart, liver or kidney is scarce. The results in Table X indicate that the fluoride content of the kidneys of mice increased with age when the dietary Ca was low and fluoride feeding resulted in much higher levels at 653 days of age irrespective of the dietary Ca content. It is likely that such high fluoride levels had an adverse effect on kidney function. In cases of chronic fluoride intoxication, kidney function was reported to be impaired in the majority of cases (18). It should be noted that fluoride accumulated in the kidneys of mice even though the capacity of bone to store fluoride (5000 yg/g dry weight) without skeletal damage was not reached. 

In summary, the results of this life-long experiment on female mice indicated that low or high Ca intake early in life did not have any significant effect on the skeletal Ca in adulthood, but the continued high Ca intake reduced the turnover rate in old age. Consequently the strengh of the bone was better preserved than that in the mice fed the low Ca diet. This supports the use of Ca supplements even in old patients suffering from osteoporosis, provided their vitamin D status is adequate. Dietary fluoride... 

These are classified as those with a requirement below one pg (microgram) per day. Elements in this class include boron, chromium, fluoride, iodine, molybdenum, nickel, selenium, cobalt and manganese. Cobalt is part of vitamin (see above). However, there appear to be no recommended dietary intakes for any of these except molybdenum. 

Standing Committee of the Scientific Evaluation of Dietary Reference Intakes, Food and Nutrition Board, and Institute of Medicine (1997). In "Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride." National Academy Press, Washington, DC. 

Fluorine is available to humans, plants and animals mainly in the form of fluoride ion (F ). Body fluoride status depends on numerous factors, including the total amount of fluoride ingested daily, its bioavailability and metabolism. The adequate intake (Al) of fluoride from all sources is set by the Standing Committee on the Scientific Evaluation of the Dietary Reference Intakes at 0.05 mg/day/kg body weight this intake is recommended for all ages above 6 months, because it confers a high level of protection against dental caries and is not associated with any known unwanted health effects [8]. 

Drinking water, beverages and fluoride-containing dentifrices are regarded as the main dietary contributors to human fluoride intake. Food has more recently been recognized as a potentially important source of fluoride. A major source of fluoride in some areas arises from its release into the environment by coal combustion, in process waters and waste from various industrial processes. 

Fig. 2. Teeth demonstrating fluorosis. A high level of dietary fluoride has resulted in much of the enamel becoming opaque in patches, giving a mottled appearance. (Reprinted with permission from [48]. Copyright 2002 Mosby International Limited.) (See Colour Plate Section at the end of this book.)...

Dietary fluoride supplements, available in the form of tablets, drops, lozenges and rinse supplements, are recommended for caries prevention by medical societies in some countries, especially if the fluoride concentration from drinking water is low. These supplements contain different quantities of fluoride, usually 0.25, 0.50 and 1.00 mg of fluoride per unit, in the form of NaF [60]. Fluoride supplements are rarely prescribed for adults. 

The major source of fluoride intake in adults is diet. Estimates for dietary fluoride intake for adults, by age groups and water fluoridation status, are presented in Table 4 [126,127,129,131,132,145-151],... 

Fluoride supplements are recommended by medical societies in some countries for caries prevention, especially if the concentration of fluoride in drinking water is low. It is likely that past use of dietary fluoride supplements has been a prime factor in the increased prevalence of dental fluorosis, a relationship which may stem from the days when fluoride supplement schedules were higher than they are today [11]. Table 7 shows a fluoride supplement dosage schedule that was approved for U.S. and Canadian children by the American Dental Association and Canadian Paediatric Society [8] and a fluoride supplement dosage schedule approved by German Nutrition Society, Austrian Nutrition Society, Swiss Society for Nutrition Research and Swiss Nutrition Association [165]. 

Total dietary fluoride intake, the most important source of fluoride in adults, is estimated to be 0.008-0.021 (average 0.016) mg/day/kg body weight for a 70-kg man in non-fluoridated areas and thus lower than Al. The total dietary intake of fluoride in fluoridated areas was about twofold higher [0.013-0.054 (average 0.03) mg/day/kg body weight for a 70-kg man]. 

K. Trautner, G. Siebert, An experimental study of bio-availability of fluoride from dietary sources in man. Arch. Oral Biol. 31 (1986) 223-228. 

D.R. Taves, Dietary intake of fluoride ashed (total fluoride) v. unashed (inorganic fluoride) analysis of individual foods, Br. J. Nutr. 49 (1983) 295-301. 

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