O trabalho abaixo demonstrou diretamente que, pelo menos a curto prazo, dietas ricas em proteínas não são deletérias aos ossos.
J Clin Endocrinol Metab. 2005 Jan;90(1):26-31. Epub 2004 Nov 16.
The impact of dietary protein on calcium absorption and kinetic measures of bone turnover in women.
Kerstetter JE, O'Brien KO, Caseria DM, Wall DE, Insogna KL.
School of Allied Health, Box U-2101, 358 Mansfield Road, University of Connecticut, Storrs, Connecticut 06269-2101, USA. Jane.Kerstetter@uconn.edu
Although high-protein diets induce hypercalciuria in humans, the source of the additional urinary calcium remains unclear. One hypothesis is that the high endogenous acid load of a high-protein diet is partially buffered by bone, leading to increased skeletal resorption and hypercalciuria. We used dual stable calcium isotopes to quantify the effect of a high-protein diet on calcium kinetics in women. The study consisted of 2 wk of a lead-in, well-balanced diet followed by 10 d of an experimental diet containing either moderate (1.0 g/kg) or high (2.1 g/kg) protein. Thirteen healthy women received both levels of protein in random order. Intestinal calcium absorption increased during the high-protein diet in comparison with the moderate (26.2 +/- 1.9% vs. 18.5 +/- 1.6%, P < 0.0001, mean +/- sem) as did urinary calcium (5.23 +/- 0.37 vs. 3.57 +/- 0.35 mmol/d, P < 0.0001, mean +/- sem). The high-protein diet caused a significant reduction in the fraction of urinary calcium of bone origin and a nonsignificant trend toward a reduction in the rate of bone turnover. There were no protein-induced effects on net bone balance. These data directly demonstrate that, at least in the short term, high-protein diets are not detrimental to bone.
MeSH Terms:
· Adult
· Bone Resorption/metabolism*
· Calcium/metabolism*
· Dietary Proteins/administration & dosage*
· Female
· Humans
· Intestinal Absorption*
· Kinetics
· Osteogenesis*
· Research Support, Non-U.S. Gov't
· Research Support, U.S. Gov't, P.H.S.
Substances:
· Dietary Proteins
· Calcium
Grant Support:
· M01-RR00125/RR/NCRR
· R01 DK52128-03/DK/NIDDK
PMID: 15546911 [PubMed - indexed for MEDLINE]
J Clin Endocrinol Metab. 2005 Jan;90(1):26-31. Epub 2004 Nov 16.