DIETARY FAT, CARBOHYDRATE BALANCE & WEIGHT MAINTENANCE

糖原储存可能在相当低或相当高的平均水平上下波动 水平，作为代谢适应的一部分，允许碳水化合物 氧化作用要与饲料中的珊瑚水合物含量相适应。这个 将被检验的假设是， 脂肪组织质量也代表和适应，影响游离脂肪 酸水平，直到脂肪氧化变得与百分比相称，与 一种特定饮食的脂肪含量。长期的体重维持将会 要归功于无处不在的维持碳水化合物的能力 通过相互调节食物摄入量到碳水化合物氧化和 反过来也一样。但是，尽管糖原储存的变化对身体几乎没有影响 体重；，脂肪组织质量的改变会导致肥胖。 在这里，可以找到一个简单的解释，为什么 富裕社会中的肥胖问题--食用“混合”饮食的人 高脂肪含量。 饮食中脂肪含量与稳态的关系 脂肪组织质量将通过对适应于 含有固定蛋白质，但碳水化合物和脂肪含量不同的饮食(12 到83%的卡路里为脂肪)。这些实验将被设计成揭示 这种关系是进步的和可逆的，这将是 证实饮食引起的肥胖症变化的适应性。一些人 动物将被饲养在密封的房间里，每24小时排气一次 小时，以测量他们的氧气消耗和二氧化碳产生。结合 营养素摄入量的测量(已校正溢出和不完整 吸收)这将允许计算动物的每日变化 碳水化合物和脂肪含量。这样的数据将允许确定如何 准确地说，碳水化合物、脂肪和能量的平衡在 随意摄取食物的条件，并检查食物是否和如何摄取 摄入量可能会随着动物体重的增加或减少而改变 糖原和/或脂肪储备。 拟议调查的总体目标是证明 膳食脂肪含量对稳态体成分的影响。 最终，这可能允许发展新陈代谢论点(除了 那些基于卡路里密度的数据)表明， 饮食中的脂肪含量可能有助于保持较低水平的体重 肥胖症。

Glycogen stores may fluctuate around rather low or rather high average levels, as part of the metabolic adaptation permitting carbohydrate oxidation to be commensurate with the diets corbohydrate contents. The hypothesis which will be tested is that an expansion or reduction of the adipose tissue mass also represents and adaptation, influencing free-fatty acid levels until fat oxidation becomes commensurate, percentage-wise, with a particular diet's fat content. Long-term weight maintenance would then be achieved thanks to the ubiquitous ability for maintaining carbohydrate balance by mutual adjustment of food intake to carbohydrate oxidation and vice-versa. But whereas changes in the glycogen stores hardly affect body weight;, alterations of the adipose tissue mass can lead to obesity. Herein could be found a simple explanation for the high incidence of obesity in affluent societies consuming "mixed" diets with a relatively high-fat content. The relationship between the fat content of the diet and the steady-state adipose tissue mass will be studied by carcass analysis of mice adapted to diets with a fixed protein, but variable carbohydrate and fat contents (12 to 83 percent calories as fat). The experiments will be designed to reveal whether this relationship is progressive and reversible, which would confirm the adaptive nature of diet-induced changes in adiposity. Some animals will be kept in hermetically sealed chambers, vented once every 24 hours, to measure their O2 consumption and CO2 production. In conjunction with measurements of nutrient intake (corrected for spillage and incomplete absorption) this will allow to calculate daily changes in the animals' carbohydrate and fat contents. Such data will allow to determine how accurately the carbohydrate, fat and energy balances are maintained under ad libitum food intake conditions, and to examine whether and how food intake may be altered in response to gains, or losses in the animal's glycogen and/or fat reserves. The general goal of the proposed investigations is to demonstrate the impact of the dietary fat content on steady-state body composition. Ultimately this may allow to develop metabolic arguments (in addition to those based on caloric density) suggesting that a reduction in the diets'fat content may facilitate weight maintenance at a lower level of adiposity.