Dietary acid-base balance, bone resorption, and calcium excretion.
Jajoo R, Song L, Rasmussen H, Harris SS, Dawson-Hughes B.
J Am Coll Nutr. 2006 Jun;25(3):224-30.
PMID: 16766781
Conclusions: Diet changes that increase renal NAE are associated with increases in serum PTH, bone resorption, and calcium excretion over a 60-day period.
Acid-base balance has an effect on bone turnover, especially on the rates of bone resorption and calcium mobilization. Bone mineral participates in the defense against acid-base disturbances, especially against metabolic acidosis (Lemann et al. 1966, Green & Kleeman 1991). The role of the bone mineral is important in the acid-base disorders, as no appreciable change in the intestinal calcium absorption occurs (Bichara et al. 1990).
In the mammalian body, mainly three hormones regulate the calcium metabolism and the bone turnover. 1,25-dihydroxycholecalciferol (vitamin D derivative) increases calcium absorption from the intestine and, indirectly, from bone. Parathyroid hormone mobilizes calcium from the bone and increases the urinary phosphate excretion. Calcitonin inhibits bone resorption (Ganong 1981). Used as drugs, these hormones are also capable of inducing acid-base disorders. Calcitonin administration (Escanero et al. 1991) and vitamin D excess (Bichara et al. 1990) have been reported to cause metabolic alkalosis.
Low vitamin D status, high bone turnover, and bone fractures in centenarians.
Passeri G, Pini G, Troiano L, Vescovini R, Sansoni P, Passeri M, Gueresi P, Delsignore R, Pedrazzoni M, Franceschi C.
J Clin Endocrinol Metab. 2003 Nov;88(11):5109-15.
PMID: 14602735
We conclude that the extreme decades of life are characterized by a pathophysiological sequence of events linking vitamin D deficiency, low serum calcium, and secondary hyperparathyroidism with an increase in bone resorption and severe osteopenia. These data offer a rationale for the possible prevention of elevated bone turnover, bone loss, and consequently the reduction of osteoporotic fractures and fracture-induced disability in the oldest olds through the supplementation with calcium and vitamin D.
A positive dose-response effect of vitamin D supplementation on site-specific bone mineral augmentation in adolescent girls: a double-blinded randomized placebo-controlled 1-year intervention.
Viljakainen HT, Natri AM, Kärkkäinen M, Huttunen MM, Palssa A, Jakobsen J, Cashman KD, Mølgaard C, Lamberg-Allardt C.
J Bone Miner Res. 2006 Jun;21(6):836-44.
PMID: 16753014
doi: 10.1359/jbmr.060302
We conclude that the current vitamin D recommendation for adolescent girls, at least in the northern latitudes, is too low to ensure sufficient vitamin D status during winter. Intake of vitamin D at rates of 10-15 μg/day aids to maintain stable S-25(OH)D concentrations during winter. Vitamin D induced BMC augmentation by decreasing bone resorption, but not affecting bone formation, which was reflected by the biochemical markers of bone turnover. Optimizing bone mineral gain in adolescence is crucial to the prevention of osteoporosis later in life. Increasing vitamin D intake to 10-15 μg/day aids in attaining this goal.
Fatigue fractures in military conscripts : A study on risk factors, diagnostics and long-term consequences
Ruohola, Juha-Petri
University of Helsinki, Faculty of Medicine, Institute of Clinical Medicine, Orthopaedics and Traumatology, Helsinki University Central Hospital
Centre of Military Medicine, Helsinki
2007-03-09
Doctoral dissertation (article-based)
It seems likely that low vitamin D levels are related to fatigue fractures, and that an increasing trend exists between TRACP-5b bone resorption marker elevation and fatigue fracture incidence. Though seldom detected by plain radiography, fatigue fractures often underlie unclear lower leg stress-related pain occurring in the distal parts of the tibia. Femoral neck fatigue fractures, when displaced, lead to long-term morbidity in a high percentage of patients, whereas, when non-displaced, they do not predispose patients to subsequent adverse complications. Importantly, an educational intervention can diminish the incidence of fracture displacement by enhancing awareness and providing instructions for earlier diagnosis of fatigue fractures
Association of low 25-hydroxyvitamin D concentrations with elevated parathyroid hormone concentrations and low cortical bone density in early pubertal and prepubertal Finnish girls.
Cheng S, Tylavsky F, Kröger H, Kärkkäinen M, Lyytikäinen A, Koistinen A, Mahonen A, Alen M, Halleen J, Väänänen K, Lamberg-Allardt C.
Am J Clin Nutr. 2003 Sep;78(3):485-92. Erratum in: Am J Clin Nutr. 2006 Jan;83(1):174.
PMID: 12936933
CONCLUSIONS: Vitamin D-deficient girls have low cortical BMD and high iPTH concentrations, which are consistent with secondary hyperparathyroidism. A low vitamin D concentration accompanied by high bone resorption (TRAP 5b) may limit the accretion of bone mass in young girls.