Aksungar F B, Sarıkaya M, Coskun A, Serteser M, Unsal I
Fehime Benli Aksungar, MD, Prof. Acıbadem Labmed Clinical Laboratories, Acıbadem University, İçerenköy Kayışdağı Caddesi, 34752 Ataşehir, Istanbul, Turkey, e-mail:
J Nutr Health Aging. 2017;21(6):681-685. doi: 10.1007/s12603-016-0786-y.
Caloric restriction (CR) is proven to be effective in increasing life span and it is well known that, nutritional habits, sleeping pattern and meal frequency have profound effects on human health. In Ramadan some Muslims fast during the day-light hours for a month, providing us a unique model of intermittent fasting (IF) in humans. In the present study, we have investigated the effects of IF versus CR on the same non-diabetic obese subjects who were followed for two years according to the growth hormone (GH)/Insulin like growth factor (IGF)-1 axis and insulin resistance.
Single-arm Interventional Human Study.
23 female subjects (Body Mass Index (BMI) 29-39, aged between 28-42years).
Follow-up is designed as 12 months of CR, after which there was a month of IF and 11 months of CR again, to be totally 24 months. Subjects' daily diets were aligned as low calorie diet during CR and during the IF period, the same subjects fasted for 15 hours in a day for a month and there was no daily calorie restriction. Nutritional pattern was changed as 1 meal in the evening and a late supper before sleeping and no eating and drinking during the day light hours in the IF model. Subjects made brisk walking twice a day during the whole follow-up including both CR and IF periods. BMI, Blood glucose, insulin, TSH, GH, HbA1c, IGF-1, Homa-IR and urinary acetoacetate levels were monitored once in three months and twice in the fasting month.
While subjects lost 1250 ± 372g monthly during the CR, in the IF period, weight loss was decreased to 473 ± 146 g. BMI of all subjects decreased gradually and as the BMI decreased, glucose, HbA1c, insulin, Homa-IR and TSH levels were decreased. GH levels were at baseline at the beginning, increased in the first six months and stayed steady during the CR and IF period than began decreasing after the IF period, while IGF-I increased gradually during the CR period and beginning with the 7th day of IF period, it decreased and kept on decreasing till the end of the follow-up. Urinary acetoacetate levels were higher during the IF period suggesting a constant lipid catabolism.
Our results suggest that, CR affects metabolic parameters positively which will help especially pre-diabetic and insulin resistant patients without any pharmacological approach. In addition IF without calorie restriction can enhance health and cellular resistance to disease without losing weight and those effects may be attributed to different signalling pathways and circulating ketones during IF. Changes observed during IF are probably due to the changes in eating and sleeping pattern and thus changes in metabolic rhythm.
热量限制（CR）已被证明对延长寿命有效，并且众所周知，营养习惯、睡眠模式和进餐频率对人类健康有深远影响。在斋月期间，一些穆斯林白天禁食一个月，为我们提供了人类间歇性禁食（IF）的独特模型。在本研究中，我们根据生长激素（GH）/胰岛素样生长因子（IGF）-1轴和胰岛素抵抗，对同一组非糖尿病肥胖受试者进行了两年的跟踪研究，比较了间歇性禁食（IF）与热量限制（CR）的效果。
单臂干预性人体研究。
23名女性受试者（体重指数（BMI）为29 - 39，年龄在28 - 42岁之间）。
随访设计为12个月的热量限制期，之后是1个月的间歇性禁食期，然后再次进行11个月的热量限制期，总计24个月。在热量限制期和间歇性禁食期，受试者的日常饮食均调整为低热量饮食。在间歇性禁食期，同一组受试者每天禁食15小时，为期一个月，且没有每日热量限制。在间歇性禁食模式下，营养模式改为晚上一餐和睡前吃一顿夜宵，白天禁食禁饮。在整个随访期间，包括热量限制期和间歇性禁食期，受试者每天进行两次快走。每三个月监测一次BMI、血糖、胰岛素、促甲状腺激素（TSH）、生长激素（GH）、糖化血红蛋白（HbA1c）、胰岛素样生长因子-1（IGF-1）、胰岛素抵抗指数（Homa-IR）和尿乙酰乙酸水平，在禁食月监测两次。
在热量限制期，受试者每月减重1250±372克，而在间歇性禁食期，体重减轻降至473±146克。所有受试者的BMI逐渐下降，随着BMI的下降，血糖、HbA1c、胰岛素、Homa-IR和TSH水平也下降。生长激素水平在开始时处于基线，在前六个月升高，在热量限制期和间歇性禁食期保持稳定，然后在间歇性禁食期后开始下降，而胰岛素样生长因子-1在热量限制期逐渐升高，从间歇性禁食期第7天开始下降，并持续下降直至随访结束。间歇性禁食期尿乙酰乙酸水平较高，表明脂质分解持续进行。
我们的数据表明，热量限制对代谢参数有积极影响，这尤其有助于糖尿病前期和胰岛素抵抗患者，且无需任何药物治疗。此外，无热量限制的间歇性禁食可在不减轻体重的情况下增强健康和细胞对疾病的抵抗力，这些影响可能归因于间歇性禁食期间不同的信号通路和循环酮体。间歇性禁食期间观察到的变化可能是由于饮食和睡眠模式的改变，进而导致代谢节律的变化。
