Burton-Freeman Britt
Department of Nutrition, University of California, Davis, CA 95616, USA.
J Nutr. 2005 Jun;135(6):1407-14. doi: 10.1093/jn/135.6.1407.
The aim of the study was to evaluate the effect of preloads differing in fatty acid composition, content, and delivery form on acute behavioral, subjective, and biological outcomes of satiety. Four energy- and volume-matched preloads were tested in normal weight men and women (n = 12 and 13, respectively), using a random, crossover design. Preloads were semisolid shakes differing in fat source [walnut or safflower (SAFF)], delivery [ground walnuts (WNT) or walnut oil (WOL)] or content [39% fat energy (SAFF, WNT, WOL) or 4% low-fat control (LFC)]. Blood was collected and subjective satiety assessed at 0 (fasting), 15, 30, and 45 min after preload consumption. Lunch (test meal) was provided thereafter. Energy intake at lunch was not affected by preload; however, subjects selected more carbohydrate, fiber-rich foods at the test meal lunch after walnut preloads than after LFC or SAFF preloads. Compared with the LFC preload, appetite satisfaction was significantly greater after SAFF and WNT, but not after WOL. Women were hungrier after SAFF than after WOL, whereas men were less hungry after SAFF and LFC than after WOL or WNT. Plasma cholecystokinin (CCK) concentrations reflected preload fat content and availability, particularly among men; CCK was higher after WOL and SAFF preloads than after LFC or WNT preloads. Plasma insulin was higher after LFC and SAFF preloads, corresponding to hunger suppression in men. Dietary restraint was associated with a blunted CCK response to preloads, whereas insulin was not affected by restraint. The results indicate that test meal energy intake after preloads containing approximately 40% walnut or safflower fat or 4% fat did not differ; however, walnut consumption may promote food patterns consistent with consuming diets higher in fiber.
本研究的目的是评估脂肪酸组成、含量和递送形式不同的预负荷对饱腹感的急性行为、主观和生物学结果的影响。采用随机交叉设计，在正常体重的男性和女性（分别为n = 12和13）中测试了四种能量和体积匹配的预负荷。预负荷为半固体奶昔，脂肪来源（核桃或红花油）、递送形式（磨碎的核桃或核桃油）或含量（39%脂肪能量或4%低脂对照）不同。在摄入预负荷后的0（空腹）、15、30和45分钟采集血液并评估主观饱腹感。此后提供午餐（测试餐）。午餐时的能量摄入不受预负荷的影响；然而，与低脂对照或红花油预负荷后相比，在食用核桃预负荷后的测试餐午餐中，受试者选择了更多富含碳水化合物和纤维的食物。与低脂对照预负荷相比，食用红花油和核桃后食欲满意度显著更高，但食用核桃油后没有。女性在食用红花油后比食用核桃油后更饥饿，而男性在食用红花油和低脂对照后比食用核桃油或磨碎的核桃后更不饥饿。血浆胆囊收缩素（CCK）浓度反映了预负荷的脂肪含量和可利用性，尤其是在男性中；食用核桃油和红花油预负荷后血浆CCK浓度高于低脂对照或磨碎的核桃预负荷后。食用低脂对照和红花油预负荷后血浆胰岛素更高，这与男性的饥饿抑制相对应。饮食限制与对预负荷的CCK反应减弱有关，而胰岛素不受限制的影响。结果表明，含有约40%核桃或红花油脂肪或4%脂肪的预负荷后测试餐的能量摄入没有差异；然而，食用核桃可能会促进与食用高纤维饮食一致的食物模式。
