Brinkworth Grant D, Buckley Jonathan D, Noakes Manny, Clifton Peter M
Commonwealth Scientific and Industrial Research Organisation - Human Nutrition, PO Box 10041 BC, Adelaide, South Australia 5000.
J Am Diet Assoc. 2010 Apr;110(4):633-8. doi: 10.1016/j.jada.2009.12.016.
A frequently cited concern of very-low-carbohydrate diets is the potential for increased risk of renal disease associated with a higher protein intake. However, to date, no well-controlled randomized studies have evaluated the long-term effects of very-low-carbohydrate diets on renal function. To study this issue, renal function was assessed in 68 men and women with abdominal obesity (age 51.5+/-7.7 years, body mass index [calculated as kg/m(2)] 33.6+/-4.0) without preexisting renal dysfunction who were randomized to consume either an energy-restricted ( approximately 1,433 to 1,672 kcal/day), planned isocaloric very-low-carbohydrate (4% total energy as carbohydrate [14 g], 35% protein [124 g], 61% fat [99 g]), or high-carbohydrate diet (46% total energy as carbohydrate [162 g], 24% protein [85 g], 30% fat [49 g]) for 1 year. Body weight, serum creatinine, estimated glomerular filtration rate and urinary albumin excretion were assessed before and after 1 year (April 2006-July 2007). Repeated measures analysis of variance was conducted. Weight loss was similar in both groups (very-low-carbohydrate: -14.5+/-9.7 kg, high-carbohydrate: -11.6+/-7.3 kg; P=0.16). By 1 year, there were no changes in either group in serum creatinine levels (very-low-carbohydrate: 72.4+/-15.1 to 71.3+/-13.8 mumol/L, high-carbohydrate: 78.0+/-16.0 to 77.2+/-13.2 mumol/L; P=0.93 time x diet effect) or estimated glomerular filtration rate (very-low-carbohydrate: 90.0+/-17.0 to 91.2+/-17.8 mL/min/1.73 m(2), high-carbohydrate: 83.8+/-13.8 to 83.6+/-11.8 mL/min/1.73 m(2); P=0.53 time x diet effect). All but one participant was classified as having normoalbuminuria at baseline, and for these participants, urinary albumin excretion values remained in the normoalbuminuria range at 1 year. One participant in high-carbohydrate had microalbuminuria (41.8 microg/min) at baseline, which decreased to a value of 3.1 microg/min (classified as normoalbuminuria) at 1 year. This study provides preliminary evidence that long-term weight loss with a very-low-carbohydrate diet does not adversely affect renal function compared with a high-carbohydrate diet in obese individuals with normal renal function.
极低碳水化合物饮食一个经常被提及的问题是，较高的蛋白质摄入量可能会增加患肾病的风险。然而，迄今为止，尚无严格对照的随机研究评估极低碳水化合物饮食对肾功能的长期影响。为研究这一问题，对68名腹部肥胖的男性和女性（年龄51.5±7.7岁，体重指数[按kg/m²计算]33.6±4.0）进行了肾功能评估，这些人无既往肾功能不全，被随机分为三组，分别摄入能量受限（约1433至1672千卡/天）、计划等热量的极低碳水化合物饮食（碳水化合物占总能量的4%[14克]，蛋白质占35%[124克]，脂肪占61%[99克]）或高碳水化合物饮食（碳水化合物占总能量的46%[162克]，蛋白质占24%[85克]，脂肪占30%[49克]），为期1年。在1年前后（2006年4月至2007年7月）评估体重、血清肌酐、估计肾小球滤过率和尿白蛋白排泄量。进行了重复测量方差分析。两组体重减轻情况相似（极低碳水化合物组：-14.5±9.7千克，高碳水化合物组：-11.6±7.3千克；P = 0.16）。到1年时，两组的血清肌酐水平均无变化（极低碳水化合物组：72.4±15.1至71.3±13.8微摩尔/升，高碳水化合物组：78.0±16.0至77.2±13.2微摩尔/升；P = 0.93，时间×饮食效应），估计肾小球滤过率也无变化（极低碳水化合物组：90.0±17.0至91.2±17.8毫升/分钟/1.73平方米，高碳水化合物组：83.8±13.8至83.6±11.8毫升/分钟/1.73平方米；P = 0.53，时间×饮食效应）。除一名参与者外，所有参与者在基线时均被分类为正常白蛋白尿，对于这些参与者，1年时尿白蛋白排泄值仍在正常白蛋白尿范围内。高碳水化合物组有一名参与者在基线时为微量白蛋白尿（41.8微克/分钟），1年时降至3.1微克/分钟（分类为正常白蛋白尿）。这项研究提供了初步证据，表明在肾功能正常的肥胖个体中，与高碳水化合物饮食相比，极低碳水化合物饮食导致的长期体重减轻不会对肾功能产生不利影响。
