Hormone Replacement Therapy (HRT) and Osteoporosis: Bone Enzymes and Nutrient Imbalances – A Short Review of the Literature and Preliminary Reports of Two Small Studies

Davies S, McLaren-Howard JMH, Grant E. J. Nutr. & Env. Med., June 1998; 8: 129-138 Contrary to popular belief the available published evidence suggests that osteoporosis is not primarily due to deficiencies of either calcium or oestrogen but is related to deficiencies of key nutrients. Serum bone alkaline phosphatase (ALP) activity is a measure of bone formation. Tartrate-resistant acid phosphatase (TRAP) is a measure of bone resorption. Low serum ALP activity relates to reduced zinc, magnesium and manganese concentrations. ALP activity improves when these nutrients are supplemented, both in vitro and in vivo, but it appears that copper decreases serum bone ALP activity. Among women with confirmed or suspected osteoporosis, all those taking hormone replacement therapy (HRT) had abnormally high serum copper levels. Hormone takers also had significantly lower white cell zinc, lower red cell magnesium and lower serum bone ALP concentrations, and significantly higher mean serum phosphate levels, than other women with osteoporosis. Hormone takers had lower serum manganese, TRAP and vitamin C levels, and higher urinary excretion of zinc and hydroxyproline but these did not reach statistical significance. These results suggest that taking exogenous steroid sex hormones is associated with a reduction in essential bone nutrients and reduced bone formation. International incidence data show that fractures among women aged 35-65 years have increased dramatically in hormone prescribing countries, and evidence is presented to indicate that this may be mediated by reduction in essential nutrients for bone formation. This study indicates the need for further research directed towards establishing the relationship between status of those nutrients essential for maintenance of bone integrity and the development of osteoporosis.