Psychological Sciences, Eleanor Rathbone Building, University of Liverpool, Liverpool, L69 7ZA, UK.
Psychological Sciences, Eleanor Rathbone Building, University of Liverpool, Liverpool, L69 7ZA, UK.
Appetite. 2015 Aug;91:83-9. doi: 10.1016/j.appet.2015.04.009. Epub 2015 Apr 9.
Larger portions increase energy intake (the 'portion size effect'); however, the mechanisms behind this effect are unclear. Although pre-meal intentions are thought to be an important determinant of energy intake, little research has examined how much of a meal individuals intend to eat when served standard versus larger portion sizes. Three studies examined the effect of manipulating portion size on intended food consumption. In Studies 1 (spaghetti bolognese) and 2 (curry and rice) male participants were shown an image of either a standard or a larger meal and indicated how much of the meal they intended to consume. In Study 3 male and female participants were served either a standard or a larger portion of ice cream for dessert, they indicated how much they intended to consume and then ate as much of the ice cream as they desired. Regardless of being shown standard or large portion sizes, in Studies 1 and 2 participants reported that they intended to eat the majority of the meal, equating to a large difference in intended energy consumption between portion size conditions (a 'pre-consumption portion size effect'). This finding was replicated in male participants in Study 3, although females intended to eat a smaller proportion of the larger portion of ice cream, compared to the standard portion. Both male and female participants tended to eat in accordance with their pre-meal intentions and a portion size effect on actual consumption was subsequently observed in males, but not in females. The portion size effect may be observed when measuring pre-meal intended consumption in males.
较大的份量会增加能量摄入（“份量大小效应”）；然而，这种效应的机制尚不清楚。尽管餐前意向被认为是能量摄入的一个重要决定因素，但很少有研究探讨个体在提供标准份量和较大份量时，打算吃多少份量的食物。三项研究检验了改变份量大小对意向食物消费的影响。在研究 1（意大利肉酱面）和研究 2（咖喱和米饭）中，男性参与者看到了标准份量和较大份量的食物图像，并表示他们打算吃多少份量的食物。在研究 3 中，男性和女性参与者被提供了标准份量或较大份量的冰淇淋作为甜点，他们表示打算吃多少份量，然后想吃多少就吃多少。无论看到的是标准份量还是较大份量，在研究 1 和研究 2 中，参与者表示他们打算吃大部分食物，这意味着在份量大小条件下，预期能量消耗存在很大差异（“预消费份量大小效应”）。在研究 3 中的男性参与者中，这一发现得到了复制，尽管女性参与者打算吃较小比例的较大份量冰淇淋，而不是标准份量。男性和女性参与者都倾向于按照他们的餐前意向进食，随后在男性中观察到了实际消费的份量大小效应，但在女性中没有观察到。在测量男性的餐前意向消费时，可能会观察到份量大小效应。
