不想減少飯量,但是想瘦,怎麼辦?
When it comes to losing weight, the most important rule of thumb is to consume fewer calories than you're taking in each day. But cutting calories doesn't have to mean eating less food. In fact, simply focusing on healthier food choices may be a more sustainable weight-loss strategy than trying to reduce portion sizes, a new Penn State University study suggests.
說到減肥這個話題，最重要的經驗法則就是：每天攝入的卡路里量少於往常的攝入量。但減少卡路里的攝入量並不一定意味着少吃食物。賓夕法尼亞州立大學的一項新研究表明：事實上，相比減少食物分量，關注更健康的食物可能是更可持續的減肥策略。
The findings come from a small new clinical trial, published in the journal Appetite, which compared food consumption among 39 women who'd taken part in a previous, year-long weight-loss study and 63 women who were not part of the earlier study. All of the women came to the study lab once a week for four weeks to eat a meal, with varying portions of seven different foods served each week.
研究發表在Appetite期刊上，研究結果源於一項小型的新的臨牀試驗，將先前參與爲時一年的減肥研究的39位女性的食物攝入與沒有參與這項研究的63位女性的食物攝入進行對比。所有女性每週都來實驗室吃一頓飯，連續四周，每週有7種不同的食物、不同的分量。
The women in the first group, as part of the previous study, had been counseled on various strategies for weight loss, including measuring out portion sizes, calculating calorie density of different foods, and making overall healthier choices. Because the training focused heavily on portion control, the researchers expected the women who'd participated in those training sessions to eat less food overall.
第一組的女性（參與了先前的研究）已經知道了各種各樣的減肥方法，包括量好食物分量、計算不同食物的卡路里密度、做出總體更健康的選擇。因爲先前的訓練主要集中於分量控制，所以研究員預期參與這些訓練的女性會吃更少的食物（整體而言）。
That didn't happen, though. Women in both groups fell victim to the "portion size effect," what researchers call the tendency to eat more when larger portions of food are presented. (For example, when meal size increased by 75%, the average amount consumed went up 27%.) Overall, there was no significant difference in total amount of food consumed, by weight, between those who'd received training and those who had not.
但情況並非如此。兩組女性都成爲"分量效應"的受害者，研究人員認爲這一效應就是，當面前有更大份額的食物時，人們往往會吃的更多。（比如，當食物分量增加75%的時候，平均攝入量增加了27%。）總的來說，對於接受訓練的女性和沒有接受訓練的女性而言，攝入的食物總量並沒有顯著差別。
But there was one difference. "When we dug into their food choices, we found that the trained participants were selecting to eat more of the lower calorie-dense foods-like salad, for example-and less of higher calorie-dense foods, such as the garlic bread," says first author Faris Zuraikat, a graduate student in the department of nutritional sciences. In other words, even though they ate the same total volume of food, they consumed fewer calories.
但也存在一個差異。"當我們研究她們的食物選擇時，我們發現：受訓參與者更多的選擇吃那些卡路里密度更低的食物--比如沙拉--不大吃那些卡路里密度更高的食物，比如蒜蓉麪包，"營養科學系研究生、第一作者Faris Zuraikat說道。換言之，雖然她們攝入了相等的食物量，但她們攝入的卡路里量卻更少。
