Orr Jeb S, Gentile Christopher L, Davy Brenda M, Davy Kevin P
Human Integrative Physiology Laboratory, Department of Human Nutrition, Foods and Exercise, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
Hypertension. 2008 Jun;51(6):1519-24. doi: 10.1161/HYPERTENSIONAHA.108.112946. Epub 2008 May 5.
We tested the hypothesis that weight gain would increase arterial stiffness in healthy nonobese adults. To address this, we overfed 14 nonobese men (age: 23+/-1 years) approximately 1000 kcal/d for 6 to 8 weeks until a 5-kg weight gain was achieved. Carotid diameters (high-resolution ultrasound) and pressures (applanation tonometry), body composition (dual energy x-ray absorptiometry), and abdominal fat distribution (computed tomography) were measured at baseline and following 4 weeks of weight stability at each individual's elevated body weight. Overfeeding increased body weight 5.1+/-0.1 kg and body fat 3.4+/-0.4 kg (both P<0.001) in 45+/-7 days. Total abdominal fat increased 46+/-7 cm(2) with weight gain due to increases in both subcutaneous (30+/-6 cm(2)) and visceral fat (15+/-4 cm(2); all P<0.01). As hypothesized, weight gain increased arterial stiffness 13+/-6% and decreased arterial compliance 21+/-4% (both P<0.05). Furthermore, those individuals above the median increase in abdominal visceral fat demonstrated a significantly greater increase in arterial stiffness (0.97+/-0.29 versus 0.06+/-0.36 U; P<0.05) compared with those below the median. Consistent with these observations, the only correlates of the changes in arterial stiffness with weight gain were the increases in total abdominal fat (r=0.794), abdominal visceral fat (r=0.651), and waist circumference (r=0.470; all P<0.05). Taken together, these findings suggest that modest weight gain is associated with increases arterial stiffness in nonobese men. The degree of large artery stiffening with weight gain seems to be determined, in part, by the amount of abdominal visceral fat gain. Importantly, this relation is independent of the amount of total body fat gained.
我们检验了体重增加会使健康非肥胖成年人动脉僵硬度增加这一假设。为了验证这一点，我们让14名非肥胖男性（年龄：23±1岁）每天过量摄入约1000千卡热量，持续6至8周，直至体重增加5千克。在基线时以及在每个个体体重升高后体重稳定4周后，测量颈动脉直径（高分辨率超声）和压力（压平式眼压测量法）、身体成分（双能X线吸收法）以及腹部脂肪分布（计算机断层扫描）。在45±7天内，过量进食使体重增加了5.1±0.1千克，体脂增加了3.4±0.4千克（均P<0.001）。由于皮下脂肪（30±6平方厘米）和内脏脂肪（15±4平方厘米）均增加，总腹部脂肪随体重增加增加了46±7平方厘米（均P<0.01）。如假设的那样，体重增加使动脉僵硬度增加了13±6%，动脉顺应性降低了21±4%（均P<0.05）。此外，与腹部内脏脂肪增加中位数以下的个体相比，腹部内脏脂肪增加中位数以上的个体动脉僵硬度增加显著更大（0.97±0.29对0.06±0.36单位；P<0.05）。与这些观察结果一致，动脉僵硬度随体重增加变化的唯一相关因素是总腹部脂肪增加（r=0.794）、腹部内脏脂肪增加（r=0.651）和腰围增加（r=0.470；均P<0.05）。综上所述，这些发现表明适度体重增加与非肥胖男性动脉僵硬度增加有关。体重增加时大动脉僵硬程度似乎部分取决于腹部内脏脂肪增加量。重要的是，这种关系独立于总体脂增加量。
