High Dietary Sodium Intake Assessed by 24-hour Urine Specimen Increase Urinary Calcium Excretion and Bone Resorption Marker

Abstract

BackgroundThe average dietary sodium intake of Koreans is 2.6 times higher than the World Health Organization's recommended amount. The effect of a diet high in sodium on the skeletal system, especially osteoporosis, has not previously been examined in Korean postmenopausal women with low bone mass. We assessed the daily sodium intake, and determined the impact of sodium intake on urinary calcium excretion and bone resorption marker.MethodsA retrospective review of medical records was performed for 86 postmenopausal subjects who were initially diagnosed with osteopenia or osteoporosis at the health promotion center. They were subsequently referred to the Division of Endocrinology and Metabolism between 2010 and 2013. All subjects completed a modified food frequency questionnaire. Twenty-four hour urine collection for sodium, calcium and creatinine excretion, and serum C-terminal telopeptides of type I collagen (CTX-I) were also obtained.ResultsThe average amount of daily sodium and calcium intake were 3,466 mg and 813 mg, respectively. Average dietary sodium intake and 24-hour urinary sodium excretion showed significant positive linear correlation (r=0.29, P=0.006). There was also a significant positive linear correlation between 24-hour urine sodium and calcium excretion (r=0.42, P<0.001); CTX-I and 24-hour urinary calcium excretion (r=0.29, P=0.007).ConclusionsExcessive sodium intake assessed by 24-hour urine specimen is associated with high calcium excretion in urine. High calcium excretion is also related to increasing bone resorption marker.

Osteoprotective action of low-salt diet requires myeloid cell–derived NFAT5

“…In accordance with earlier studies, we show that disturbances in the Na + balance are linked with osteopenia and reduced bone density in various studies (21,(30)(31)(32)37).…”

“…These include cutaneous Na + storage and induction of a macrophage-driven cutaneous response, which facilitates Na + mobilization from the skin to avoid excess increases in blood pressure (23)(24)(25). This critically involves the activity of the osmoprotective transcription factor nuclear factor of activated T cell 5 (NFAT5, also known as tonicity-dependent enhancer binding protein [TonEBP]), which can be induced by osmotic stress in a calcineurin-independent manner (26)(27)(28) Surprisingly, both hyponatremia and Na + -rich diets are linked to osteopenia (21,(29)(30)(31)(32)(33)(34)(35)(36)(37). Osteoclasts, which are derived from mononuclear phagocytes, play a major role in bone resorption and remodeling (1,2).…”

Protective Effect of Zinc; Against Salt Induced Macroscopic Changes in Humerus and Femur of Rats

“…18 Increase sodium intake is a risk factor for osteoporosis. 19,20 due to change in bone mineral density and detrimental effect on calcium homeostasis. 21,22 Zinc is a component of more than 200 enzymes 14,23 and 23 most abundant element in the earth's crust with enzymatic function reduces osteoclast resorption activities and increase markers of osteoblast differentiation, matrix maturation and mineralization.…”

“…20,21 The reason for disturbance in Ca homeostasis may be due to the fact that decrease serum calcium stimulates PTH secretion leading to increased bone resorption and decrease bone weight. Hence, it can be concluded from my and other studies that may be if the research is carried out for prolonged period, there could be more significant results regarding bone weight.…”

Lifestyle Behaviors Affecting Bone Health in Young Hispanic and Non-Hispanic White Women

“…2 High dietary intakes of protein, sodium, and caffeine may also negatively impact bone health, particularly among individuals who do not consume sufficient dietary calcium. [6][7][8] Other protective lifestyle behaviors include consuming adequate energy through a well-balanced and nonrestrictive diet, exercising regularly, limiting excessive alcohol consumption, and avoiding smoking. 2,[9][10][11][12][13][14] Although bone mass develops and peaks during adolescence and early adulthood, adequate maintenance throughout adulthood is necessary to reduce the rate of natural bone loss and offset the effects of osteoporosis in later years.…”