title: Short-term effects on bone turnover of replacing milk with cola beverages: a 10-day interventional study in young men.
abstract: In the Western world, increased consumption of carbonated soft drinks combined with a decreasing intake of milk may increase the risk of osteoporosis. This study was designed to reflect the trend of replacing milk with carbonated beverages in a group of young men on a low-calcium diet and studies the effects of this replacement on calcium homeostasis and bone turnover. This controlled crossover intervention study included 11 healthy men (22-29 years) who were given a low-calcium basic diet in two 10-day intervention periods with an intervening 10-day washout. During one period, they drank 2.5 l of Coca Cola per day and during the other period 2.5 l of semi-skimmed milk. Serum concentrations of calcium, phosphate, 25-hydroxycholecalciferol, 1,25-dihydroxycholecalciferol (1,25(OH)2D), osteocalcin, bone-specific alkaline phosphatase (B-ALP) and cross-linked C-telopeptides (CTX), plasma intact parathyroid hormone (PTH) and urinary cross-linked N-telopeptides (NTX) were determined at baseline and endpoint of each intervention period. An increase in serum phosphate (P<0.001), 1,25(OH)2D (P<0.001), PTH (P=0.046) and osteocalcin (P<0.001) was observed in the cola period compared to the milk period. Also, bone resorption was significantly increased following the cola period, seen as increased serum CTX (P<0.001) and urinary NTX (P<0.001) compared to the milk period. No changes were observed in serum concentrations of calcium or B-ALP. This study demonstrates that over a 10-day period high intake of cola with a low-calcium diet induces increased bone turnover compared to a high intake of milk with a low-calcium diet. Thus, the trend towards a replacement of milk with cola and other soft drinks, which results in a low calcium intake, may negatively affect bone health as indicated by this short-term study.
authors.affiliation: Department of Human Nutrition and Center for Advanced Food Studies (LMC), The Royal Veterinary and Agricultural University, Rolighedsvej 30, 1958, Frederiksberg, Denmark.
authors.forename: Mette
authors.initials: M
authors.lastname: Kristensen
authors.forename: Marlene
authors.initials: M
authors.lastname: Jensen
authors.forename: Jane
authors.initials: J
authors.lastname: Kudsk
authors.forename: Marianne
authors.initials: M
authors.lastname: Henriksen
authors.forename: Christian
authors.initials: C
authors.lastname: Mølgaard
mesh_terms: D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D000818:Animals; D015415:Biomarkers / Q000097:blood; D001842:Bone and Bones / Q000378:metabolism*; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002136:Calcium, Dietary / Q000008:administration & dosage* / Q000378:metabolism; D002253:Carbonated Beverages; D003094:Collagen / Q000097:blood; D024042:Collagen Type I; D018592:Cross-Over Studies; D004032:Diet / Q000009:adverse effects*; D006706:Homeostasis / Q000502:physiology; D006801:Humans; D008297:Male; D008892:Milk; D015675:Osteocalcin / Q000097:blood; D010024:Osteoporosis / Q000097:blood / Q000209:etiology; D010281:Parathyroid Hormone / Q000097:blood; D010455:Peptides / Q000097:blood; D010710:Phosphates / Q000097:blood
chemical_list: D015415:Biomarkers; D002136:Calcium, Dietary; D024042:Collagen Type I; D010281:Parathyroid Hormone; D010455:Peptides; D010710:Phosphates; C052929:collagen type I trimeric cross-linked peptide; D015675:Osteocalcin; D003094:Collagen; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002112:Calcifediol