Abstract

OBJECTIVE:  To study the effects of excess fluoride on bone turnover under conditions of diet containing different amount of calcium.

METHODS:  The experiment was performed on rats raised on a balanced diet with adequate calcium or a monotonous diet with low calcium and given amount of fluoride in their drinking water (F, 100 mg/L) for 2 months or 1 year.

RESULTS:  Osteomalacia, osteoporosis and accelerated bone turnover were observed with elevated serum alkaline phosphatase (ALP), osteocalcin (BGP) and parathyroid hormone (PTH) in rats fed on low calcium diet and fluoridized water for 2 months. In the rats fed on adequate calcium diet and fluoridized water for 2 months, only slightly increased osteoblastic activity was found while the average width of trabecular bone was increased with elevated serum ALP activity in rats raised on the same diet and water for 1 year.

CONCLUSIONS:  The basic effect of excess fluoride on bone is the causation of a high bone turnover state which can also be induced to a milder extent by low calcium diet itself. Therefore, the formation of a high bone turnover state is the pathogenetic basis for low dietary calcium intake to exacerbate the severity of skeletal fluorosis.

• Related Studies :

  • Endemic chronic fluoride toxicity and dietary calcium deficiency interaction syndromes of metabolic bone disease and deformities in India: year 2000

    Epidemiological studies during 1963-1997 were conducted in 45,725 children exposed to high intake of endemic fluoride in the drinking water since their birth. Children with adequate (dietary calcium > 800 mg/d) and inadequate (dietary calcium < 300 mg/d) calcium nutrition and with comparable intakes of fluoride (mean 9.5 +/- 1.9

  • Histomorphometric analysis of iliac crest bone biopsies in placebo-treated versus fluoride-treated subjects

    In a 4-year controlled, prospective trial, histomorphometric analysis was used to compare the tissue-level skeletal effects of fluoride therapy in 43 postmenopausal women (75 mg NaF/day) with those of 35 matching placebo subjects; all subjects received 1500 mg/day elemental calcium supplement. In addition to an initial, baseline biopsy, a second

  • The spectrum of radiographic bone changes in children with fluorosis

    Painful, crippling deformities in Tanzanian children from an area of endemic fluorosis are reported. Excessive fluoride ingestion in pregnant women may possibly poison and alter enzyme and hormonal systems in the fetus causing disturbances to osteoid formation and mineralization. Knock-knees, bowlegs, and saber shins develop when walking begins. Combinations of osteomalacia, osteoporosis,

  • Calcium deficiency in fluoride-treated osteoporotic patients despite calcium supplementation

    To test the hypothesis that the osteogenic response to fluoride can increase the skeletal requirement for calcium, resulting in a general state of calcium deficiency and secondary hyperparathyroidism, we assessed calcium deficiency, spinal bone density, by quantitative computed tomography, and serum PTH in three groups of osteoporotic subjects. Two of

  • Endemic skeletal fluorosis in children: hypocalcemia and the presence of renal resistance to parathyroid hormone

    Although endemic skeletal fluorosis has been reported in children, hypocalcemia has not been previously noted. In a prevalence study of 260 schoolchildren living in an endemic fluorosis area in South Africa (water fluoride content 8-12 ppm), hypocalcemia was documented in 23%. Furthermore in a separate study of nine children with skeletal symptoms due to

• Related FAN Content :

  • Fluoride Exposure Increases Metabolic Requirement for Calcium & Vitamin D

    It is well known that individuals with nutrient deficiencies are more susceptible to fluoride toxicity, including fluoride's bone effects. As discussed in the following studies, fluoride increases the skeleton's need for calcium (and vitamin D) by increasing the amount of unmineralized tissue (osteoid) in the bone. When insufficient calcium and

  • Fluoridation, Dialysis & Osteomalacia

    In the 1960s and 1970s, doctors discovered that patients receiving kidney dialysis were accumulating very high levels of fluoride in their bones and blood, and that this exposure was associated with severe forms of osteomalacia, a bone-softening disease that leads to weak bones and often excruciating bone pain. Based on

  • Fluoride & Rickets

    One of fluoride's most well-defined effects on bone tissue is it's ability to increase the osteoid (unmineralized bone) content of bone. When bones have too much osteoid, they become soft and prone to fracture -- a condition known as osteomalacia. When osteomalacia develops during childhood, it is called "rickets." The potential for fluoride

  • Nutrient Deficiencies Enhance Fluoride Toxicity

    It has been known since the 1930s that poor nutrition enhances the toxicity of fluoride. As discussed below, nutrient deficiencies have been specifically linked to increased susceptibility to fluoride-induced tooth damage (dental fluorosis), bone damage (osteomalacia), neurotoxicity (reduced intelligence), and mutagenicity. The nutrients of primary importance appear to be calcium,

  • Fluoridation of drinking water and chronic kidney disease: Absence of evidence is not evidence of absence

    A fairly substantial body of research indicates that patients with chronic renal insufficiency are at an increased risk of chronic fluoride toxicity. Patients with reduced glomerular filtration rates have a decreased ability to excrete fluoride in the urine. These patients may develop skeletal fluorosis even at 1 ppm fluoride in the drinking water.