Alkaline Salts to Counteract Bone Resorption and Protein Wasting Induced by High Salt Intake: Results of a Randomized Controlled Trial

• Published in: The journal of clinical endocrinology and metabolism Vol. 97; no. 12; pp. 4789 - 4797
• Main Authors: Buehlmeier, Judith, Frings-Meuthen, Petra, Remer, Thomas, Maser-Gluth, Christiane, Stehle, Peter, Biolo, Gianni, Heer, Martina
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Oxford University Press 01.12.2012; Endocrine Society
• Subjects: Acidosis; Adult; Alkalies - administration & dosage; Alkalies - pharmacology; Alkalies - therapeutic use; Bicarbonates - administration & dosage; Bicarbonates - pharmacology; Bicarbonates - therapeutic use; Biological and medical sciences; Bone and Bones - drug effects; Bone and Bones - metabolism; Bone resorption; Bone Resorption - etiology; Bone Resorption - prevention & control; Calcium (urinary); Collagen (type I); Cross-Over Studies; Dietary Supplements; Eating - drug effects; Eating - physiology; Endocrinopathies; Excretion; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; Humans; Long bone; Male; Medical sciences; Metabolic acidosis; Metabolism; Models, Biological; Musculoskeletal system; Potassium Compounds - administration & dosage; Potassium Compounds - pharmacology; Potassium Compounds - therapeutic use; Protein turnover; Proteins; Proteins - drug effects; Proteins - metabolism; Salts - administration & dosage; Salts - pharmacology; Salts - therapeutic use; Sodium chloride; Sodium Chloride, Dietary - adverse effects; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Vertebrates: endocrinology; Wasting Syndrome - etiology; Wasting Syndrome - prevention & control; Young Adult; Obesity; Nutrition; Nutrition disorder; Resorption; Metabolic diseases; Protein; Result; Osteoarticular system; Salt; Randomization; Randomised controlled trial; Clinical trial; Bone; Endocrinology; Nutritional status
• ISSN: 0021-972X; 1945-7197; 1945-7197
• DOI: 10.1210/jc.2012-2857

High sodium chloride (NaCl) intake can induce low-grade metabolic acidosis (LGMA) and may thus influence bone and protein metabolism.We hypothesized that oral potassium bicarbonate (KHCO3) supplementation may compensate for NaCl-induced, LGMA-associated bone resorption and protein losses. Eight healthy male subjects participated in a randomized trial with a crossover design. Each of two study campaigns consisted of 5 d of dietary and environmental adaptation followed by 10 d of intervention and 1.5 d of recovery. In one study campaign, 90 mmol KHCO3/d were supplemented to counteract NaCl-induced LGMA, whereas the other campaign served as a control with only high NaCl intake.When KHCO3 was ingested during high NaCl intake, postprandial buffer capacity ([HCO3−]) increased (P = 0.002). Concomitantly, urinary excretion of free potentially bioactive glucocorticoids [urinary free cortisol (UFF) and urinary free cortisone (UFE)] was reduced by 14% [∑(UFF,UFE); P = 0.024]. Urinary excretion of calcium and bone resorption marker N-terminal telopeptide of type I collagen was reduced by 12 and 8%, respectively (calcium, P = 0.047; N-terminal bone collagen telopeptide, P = 0.044). There was a trend of declining net protein catabolism when high NaCl was combined with KHCO3 (P = 0.052).We conclude that during high salt intake, the KHCO3-induced postprandial shift to a more alkaline state reduces metabolic stress. This leads to decreased bone resorption and protein degradation, which in turn might initiate an anticatabolic state for the musculoskeletal system in the long run.