Department of Environmental Health Sciences, School of Public Health, University of Alabama at Birmingham , Birmingham, AL , USA ; Office of Energetics and Nutrition Obesity Research Center, University of Alabama at Birmingham , Birmingham, AL , USA.
Office of Energetics and Nutrition Obesity Research Center, University of Alabama at Birmingham , Birmingham, AL , USA.
Front Nutr. 2015 Aug 24;2:20. doi: 10.3389/fnut.2015.00020. eCollection 2015.
We hypothesized that exposure to temperatures above the thermoneutral zone (TNZ) would decrease food intake in young adults in a sedentary office environment over a 2-h period.
Participants wearing standardized clothing were randomized to perform routine office work in the TNZ, considered control (19-20°C), or above the TNZ considered warmer (26-27°C) using a parallel-group design (n = 11 and 9, respectively). Thermal images of the inner canthus of their eye and middle finger nail bed, representing proxies of core and peripheral temperatures, respectively, were taken at baseline, first, and second hour during this lunchtime study. Heat dissipation was estimated using peripheral temperature. General linear models were built to examine the effects of thermal treatment on caloric intake and potential mediation by heat dissipation. Researchers conducted the trial registered as NCT02386891 at Clinicaltrials.gov during April to May 2014.
During the 2-h stay in different ambient temperatures, the participants in the control conditions ate 99.5 kcal more than those in the warmer conditions; however, the difference was not statistically significant. Female participants ate about 350 kcal less than the male participants (p = 0.024) in both groups and there was no significant association between caloric intake and participant's body mass index (BMI). After controlling for thermal treatment, gender and BMI, the participant's peripheral temperature was significantly associated with caloric intake (p = 0.002), suggesting a mediating effect. Specifically, for every 1°C increase in peripheral temperature suggesting increased heat dissipation, participants ate 85.9 kcal less food.
This pilot study provided preliminary evidence of effects of thermal environment on food intake. It suggests that decreased food intake in the experimental (warmer) environment is potentially mediated through thermoregulatory mechanisms.
我们假设，在久坐的办公环境中，年轻人在超过 2 小时的时间里处于热中性区（TNZ）以上的温度会导致食物摄入量减少。
参与者穿着标准化的服装，随机分配到 TNZ 中进行常规办公（视为对照，19-20°C），或在高于 TNZ 的更温暖环境（26-27°C）中进行办公，采用平行组设计（分别为 11 人和 9 人）。在这项午餐时间研究中，在基线、第一小时和第二小时，用热像仪拍摄他们的眼角内侧和中指甲床的图像，分别代表核心和外周温度的代表。使用外周温度估计散热。建立了一般线性模型来检查热处理对热量摄入的影响，以及潜在的散热介导作用。研究人员于 2014 年 4 月至 5 月在 Clinicaltrials.gov 上以 NCT02386891 号进行了试验。
在不同环境温度下的 2 小时停留期间，对照组参与者比实验组参与者多吃了 99.5 卡路里的食物，但差异无统计学意义。在两组中，女性参与者比男性参与者少吃约 350 卡路里（p=0.024），并且参与者的体质量指数（BMI）与热量摄入之间没有显著关联。在控制了热处理、性别和 BMI 后，参与者的外周温度与热量摄入显著相关（p=0.002），表明存在中介效应。具体而言，外周温度每升高 1°C，表明散热增加，参与者摄入的食物就会减少 85.9 卡路里。
这项初步研究提供了热环境对食物摄入影响的初步证据。它表明，实验（较温暖）环境中食物摄入量减少可能是通过体温调节机制介导的。
