School of Dietetics and Human Nutrition, McGill University, Montreal, Canada.
Chronobiol Int. 2011 Apr;28(3):216-28. doi: 10.3109/07420528.2010.548614.
The eating pattern is altered by high-fat diet-induced obesity. To clarify whether this is dependent on the fatty acid profile of the diet, the authors conducted two studies on adult female Sprague-Dawley rats fed normal-fat chow or high-fat diets with varying fatty acid composition. Eating pattern and body weight were assessed in rats fed canola-based (low in saturated fatty acids) or lard-based (moderate in saturated fatty acids) diets for 7 days, and in animals fed chow or canola- or butter-based diets (rich in saturated fatty acids) for 43 days. These parameters were also determined when restricted amounts of low-fat canola- or butter-based diets were consumed for 25 days. Early exposure to canola or lard high-fat feeding or prolonged access to canola- or butter-based fat-rich diets (relative to chow feeding) did not alter the normal light-dark distribution of food and energy intake. All animals ingested most of their food during the dark phase. However, feeding the high-fat canola- and butter-based diets produced an altered eating pattern during the light phase characterized by a smaller number of meals, longer intermeal interval, and enhanced satiety ratio, and consumption of shorter-lasting meals than chow-fed animals. Relative to canola or chow feeding, butter-fed animals consumed a lower number of meals during the dark phase and had a higher eating rate in the light phase, but ate larger meals overall. Only butter feeding led to overeating and obesity. When given a restricted amount of low-fat canola- or butter-based diet at the start of the light phase, rats ate most of their food in that phase and diurnal rather than nocturnal feeding occurred with restriction. These findings underscore the role of saturated fatty acids and the resulting eating pattern alteration in the development of obesity.
饮食习惯会因高脂肪饮食引起的肥胖而改变。为了明确这是否取决于饮食中的脂肪酸组成，作者对成年雌性 Sprague-Dawley 大鼠进行了两项研究，分别用正常脂肪含量的饲料和不同脂肪酸组成的高脂肪饲料喂养。作者在大鼠中评估了饮食模式和体重，这些大鼠食用菜籽油（饱和脂肪酸含量低）或猪油（饱和脂肪酸含量适中）为基础的饮食 7 天，以及食用标准饲料或菜籽油或黄油（富含饱和脂肪酸）为基础的饮食 43 天。当大鼠摄入限量的低脂肪菜籽油或黄油为基础的饮食 25 天时，也确定了这些参数。早期接触菜籽油或猪油高脂肪喂养或长期摄入菜籽油或黄油高脂肪饮食（相对于标准饲料喂养）并没有改变食物和能量摄入的正常昼夜分布。所有动物在夜间摄入大部分食物。然而，食用高脂肪菜籽油和黄油饮食会在白天导致进食模式改变，表现为进食次数减少、进食间隔延长、饱食感增强，以及进食时间较短的餐数增加，与标准饲料喂养的动物相比。与菜籽油或标准饲料喂养相比，黄油喂养的动物在夜间进食次数较少，在白天进食速度较快，但总体上进食量较大。只有黄油喂养会导致过度进食和肥胖。当在白天开始限制食用低脂肪的菜籽油或黄油饮食时，大鼠在那个阶段摄入了大部分食物，并且出现了昼夜而非夜间的进食模式，并且受到了限制。这些发现强调了饱和脂肪酸的作用以及由此导致的进食模式改变在肥胖发展中的作用。
