Brinkworth Grant D, Wycherley Thomas P, Noakes Manny, Buckley Jonathan D, Clifton Peter M
Commonwealth Scientific and Industrial Research Organisation, Food and Nutrition Flagship, Adelaide, South Australia, Australia.
University of South Australia, School of Health Sciences, Adelaide, South Australia, Australia.
Nutrition. 2016 Sep;32(9):1033-6. doi: 10.1016/j.nut.2016.03.003. Epub 2016 Mar 17.
Compromised bone health is a frequently cited concern of very-low-carbohydrate (LC) diets, although limited data are available from long-term, well-controlled, randomized studies. This study compared the effects of an energy-restricted LC diet and traditional, higher-carbohydrate, low-fat (LF) diet on bone health after 12 mo.
One hundred eighteen abdominally obese adults were randomized to consume either an energy-restricted (∼6-7 MJ/d [∼1450-1650 kcal/d]), planned isocaloric LC, or LF diet for 12 mo. Body weight, total body bone mineral content and bone mineral density (BMD), and serum bone crosslaps were assessed pre- and postintervention.
Sixty-five participants completed the study (LC = 32, LF = 33; age: 51.3 ± 7.1 y; BMI: 33.4 ± 4.0 kg/m(2)). Weight loss was similar in both groups (LC: -14.5 ± 9.8 kg, LF: -11.7 ± 7.3 kg; P = 0.26). By 1 y, total body bone mineral content had not changed in either group (LC: 2.84 ± 0.47 to 2.88 ± 0.49 kg, LF: 3.00 ± 0.52 to 3.00 ± 0.51 kg; P = 0.07 time × diet effect). In both groups, total body BMD decreased (LC: 1.26 ± 0.10 to 1.22 ± 0.09 g/cm(2), LF: 1.26 ± 0.09 to 1.23 ± 0.08 g/m(2); P < 0.001 time) and bone serum crosslaps increased (LC: 319.3 ± 142.6 to 396.5 ± 172.0 ng/L, LF: 276.3 ± 100.6 to 365.9 ± 154.2 ng/L; P < 0.001 time) independent of diet composition (P ≥ 0.25 time × diet effect). Future studies would be strengthened by the assessment of regional BMD at clinically relevant sites (i.e., hip and spine) and multiple markers of bone turnover.
Weight loss following a hypocaloric LC diet compared with an LF diet does not differentially affect markers of bone health over 12 mo in overweight and obese adults.
尽管长期、严格控制的随机研究数据有限，但骨骼健康受损是极低碳水化合物（LC）饮食中经常被提及的问题。本研究比较了能量限制的LC饮食和传统的高碳水化合物、低脂（LF）饮食在12个月后对骨骼健康的影响。
118名腹部肥胖的成年人被随机分配，食用能量限制（约6 - 7兆焦耳/天[约1450 - 1650千卡/天]）、计划等热量的LC或LF饮食，为期12个月。在干预前后评估体重、全身骨矿物质含量和骨密度（BMD）以及血清骨交联。
65名参与者完成了研究（LC组 = 32人，LF组 = 33人；年龄：51.3 ± 7.1岁；体重指数：33.4 ± 4.0千克/平方米）。两组体重减轻情况相似（LC组：-14.5 ± 9.8千克，LF组：-11.7 ± 7.3千克；P = 0.26）。到1年时，两组全身骨矿物质含量均未改变（LC组：2.84 ± 0.47至2.88 ± 0.49千克，LF组：3.00 ± 0.52至3.00 ± 0.51千克；P = 0.07时间×饮食效应）。两组全身BMD均下降（LC组：1.26 ± 0.10至1.22 ± 0.09克/平方厘米，LF组：1.26 ± 0.09至1.23 ± 0.08克/平方米；P < 0.001时间），血清骨交联增加（LC组：319.3 ± 142.6至396.5 ± 172.0纳克/升，LF组：276.3 ± 100.6至365.9 ± 154.2纳克/升；P < 0.001时间），且与饮食组成无关（P ≥ 0.25时间×饮食效应）。通过评估临床相关部位（即髋部和脊柱）的局部BMD以及多种骨转换标志物，未来的研究将得到加强。
与LF饮食相比，低热量LC饮食导致的体重减轻在12个月内对超重和肥胖成年人的骨骼健康标志物没有差异影响。
