Relationship among dietary estimates of net endogenous acid production, bone\ud mineral density and biochemical markers of bone turnover in an Iranian\ud general population

摘要

Chronic, low-grade metabolic acidosis due toWestern diets may be a risk factor for osteoporosis. The severity\udcan be determined in part by net endogenous acid production (NEAP). In a population-based study, a total of\ud1028 healthy men and women aged 20–72 years were evaluated for dietary intakes and NEAP estimates with\uda validated food frequency questionnaire. Dual-energy X-ray absorptiometry (DXA) was used to determine\udBMD of the lumbar spine (L2–L4), distal third of radius, and proximal femur. Serum CrossLaps, degradation\udproducts of the C-terminal telopeptides of type I collagen, and osteocalcin were measured by highly specific\udELISA methods. Lower estimates of energy-adjusted rates of NEAP were associated with greater femoral neck\udBMD (p=0.01) in premenopausal women and with greater BMDs at the distal radius (p=0.001) and lumbar\udspine (p=0.04) in postmenopausal women. Compared with women in the highest quartile of the estimates\udof the energy-adjusted rates of NEAP, pre- and postmenopausal women in the lowest quartile had\udsignificantly greater means of osteocalcin [9.12 (SD±1.62) vs. 5.24 (SD±1.41) ng/ml, p=0.02 and 11.74\ud(SD±1.69) vs. 7.79 (SD±2.63) ng/ml, p=0.002, respectively]. Analysis by quartiles of the estimates of\udenergy-adjusted rates of NEAP did not reveal a relationship between BMD and bone turnover markers in\udmen. In conclusion, we found that a high energy-adjusted rate of NEAP was associated with a significantly\udlower BMD in women but not in men and the energy-adjusted rate of NEAP had a negative relationship with\udbone formation.