English to Chinese Medical Medical (general)

Thinking that "2 percent milk fat" means what it says. It doesn't mean that only 2 percent of the calories you're drinking come from fat. In reality, 35 percent of the calories in a single serving of 2-percent milk come from fat, most of it saturated. It's just clever marketing. The manufacturers are referring to total volume, not caloric content.
试译：
对“乳脂含量2%”信以为真。这并非意味着你所摄入的热量当中只有2%来自脂肪。实际上，一盒乳脂含量2%的牛奶多达35%的热量来自脂肪，而且大多数是饱和脂肪。这只是精明的营销手法。厂家指的是总的含量，而不是里面所含的热量。
这个总量指的是什么总量？