Archer Edward, Thomas Diana M, McDonald Samantha M, Pavela Gregory, Lavie Carl J, Hill James O, Blair Steven N
Curr Probl Cardiol. 2016 Nov-Dec;41(11-12):268-292. doi: 10.1016/j.cpcardiol.2016.10.007. Epub 2016 Oct 20.
The purpose of this study was to examine the validity of the 1971-2010 United States Department of Agriculture's (USDA's) loss-adjusted food availability (LAFA) per capita caloric consumption estimates. Estimated total daily energy expenditure (TEE) was calculated for nationally representative samples of US adults, 20-74 years, using the Institute of Medicine's predictive equations with "low-active" (TEE L-ACT) and "sedentary" (TEE SED) physical activity values. TEE estimates were subtracted from LAFA estimates to create disparity values (kcal/d). A validated mathematical model was applied to calculate expected weight change in reference individuals resulting from the disparity. From 1971-2010, the disparity between LAFA and TEE L-ACT varied by 394kcal/d-(P < 0.001), from -205kcal/d (95% CI: -214, -196) to +189kcal/d (95% CI: 168, 209). The disparity between LAFA and TEE SED varied by 412kcal/d (P < 0.001), from -84kcal/d (95% CI: -93, -76) to +328kcal/d (95% CI: 309, 348). Our model suggests that if LAFA estimates were actually consumed, reference individuals would have lost ~1-4kg/y from 1971-1980 (an accumulated loss of ~12 to ~36kg), and gained ~3-7kg/y from 1988-2010 (an accumulated gain of ~42 to ~98kg). These estimates differed from the actual measured increments of 10kg and 9kg in reference men and women, respectively, over the 39-year period. The USDA LAFA data provided inconsistent, divergent estimates of per capita caloric consumption over its 39-year history. The large, variable misestimation suggests that the USDA LAFA per capita caloric intake estimates lack validity and should not be used to inform public policy.
本研究的目的是检验美国农业部（USDA）1971 - 2010年经损失调整的人均热量消耗食物可获得量（LAFA）估计值的有效性。使用美国国家医学院的预测方程，针对年龄在20 - 74岁的具有全国代表性的美国成年人样本，计算了估计的每日总能量消耗（TEE），采用“低活动量”（TEE L - ACT）和“久坐不动”（TEE SED）的身体活动值。从LAFA估计值中减去TEE估计值以得出差异值（千卡/天）。应用一个经过验证的数学模型来计算因该差异导致的参考个体预期体重变化。在1971 - 2010年期间，LAFA与TEE L - ACT之间的差异变化为394千卡/天（P < 0.001），从 - 205千卡/天（95%置信区间：- 214，- 196）到 + 189千卡/天（95%置信区间：168，209）。LAFA与TEE SED之间的差异变化为412千卡/天（P < 0.001），从 - 84千卡/天（95%置信区间：- 93，- 76）到 + 328千卡/天（95%置信区间：309，348）。我们的模型表明，如果实际摄入的是LAFA估计值，参考个体在1971 - 1980年期间每年会减重约1 - 4千克（累计减重约12至约36千克），在1988 - 2010年期间每年会增重约3 - 7千克（累计增重约42至约98千克）。在这39年期间，这些估计值与参考男性和女性实际测量的体重增加量分别为10千克和9千克有所不同。美国农业部的LAFA数据在其39年的历史中提供了不一致、有差异的人均热量消耗估计值。这种巨大的、可变的错误估计表明，美国农业部的LAFA人均热量摄入估计值缺乏有效性，不应被用于为公共政策提供信息。
