There are many kinds of foods. They differ from① each other in shape， colour， smell and taste. However， they are the same in one important way—they give our bodies what they need to live.
The body-building foods are mainly proteins， which have two kinds： animal proteins (or complete proteins) and vegetable proteins (or incomplete proteins).The animal protein foods are meat， fish， eggs， and milk products. Vegetable proteins are found in the cereal grains (wheat， rye， and oats) and the legumes (peas， beans， and lentils). In the absence of② sufficient fat and carbohydrate， protein can provide fuel for our bodies. Mineral is also very important in body-building. Calcium， which is rich in③ milk， cheese， eggs and green leafy vegetables， helps to build strong bones and teeth. Iron makes red blood cells. Many foods， such as liver， egg yolk， beans and leafy vegetables， have plenty of④ iron. Iodine is another important mineral. It is necessary for the thyriod gland. Seafood and iodized salt are examples of foods that have a lot of iodine.
The energy-giving foods， which are generally called carbohydrates， come mainly from plants which contain plenty of starch or sugar. Starch is in bread， rice， potatoes， and so on⑤. Sugar is often found in fruits and other sweets， like honey， syrup， etc. Fatty and oily foods give energy too. Fat gives twice as much energy as starch and sugar. The body needs a long time to use energy from fats， so the body keeps the fat under the skin to protect the body.
Most foods contain very small amount of vitamins. They are extremely important for the body. They help the body take the energy from foods， help the body grow， and help muscles work correctly. However， in most cases vitamins can’t be made inside the body. Nowadays， most of what we eat has been processed. And many of these processes take a lot of vitamins out of food. Besides， over-cooking foods， especially vegetables， can destroy the vitamins. All these should be paid special attention to⑥ when we choose or cook our food.
① differ from与……不同
② in the absence of缺乏
③ be rich in在……丰富(富有)
④ plenty of大量的
⑤ so on等等
⑥ be paid special attention to…… (应)受到特别关注
食物常识
食物种类繁多。它们虽然在色、香、味以及形状等方面各有差异，但有一个重要的方面是一致的——为我们的身体提供所需要的营养。
促进身体生长发育的食物主要是蛋白质。蛋白质分为两大类：动物蛋白(也叫完全蛋白)和植物蛋白(又称为不完全蛋白)。动物蛋白食物有肉、鱼、蛋以及奶制品等。植物蛋白则富含于各种谷类食物(小麦、裸麦、燕麦)和豆科类食物(碗豆、蚕豆、扁豆)中。在身体缺乏脂肪和碳水化合物时，蛋白质便会向身体提供它所需要的“燃料”。矿物质在身体的生长发育中也起着重要的作用。钙能壮骨健齿，它富含于奶类、乳酪、蛋和绿叶蔬菜中。铁有助于红血细胞的生成。许多食物，如肝、蛋黄、豆类、绿叶蔬菜等，都含有丰富的铁。碘是另一种重要的矿物质。它是维持甲状腺正常机能所必不可少的物质。海鲜、碘盐等便是食品中含碘丰富的代表。
向身体提供能量的食物一般统称为碳水化合物，主要来自含有大量淀粉和糖的植物类食物。富含淀粉的食物有面包、大米和薯类等。糖则常见于各种水果以及像蜂蜜、糖浆等甜食中。此外，脂肪和油类食物也提供能量。脂肪所提供的能量是淀粉和糖的两倍。但身体吸收利用脂肪所提供的能量需要花很长的时间。因此，身体总是将脂肪储存在皮下来为自身提供保护。
多数食物都含有微量的维生素。维生素对于身体是极其重要的。它们有助于身体从食物中获取能量，有助于身体的生长发育，有助于身体各部的肌肉运动协调准确。然而，在多数情况下维生素不能在体内生成。如今，我们所食用的大部分食品都经过了加工制作，而许多这些加工过程都会使食物中的维生素大量流失。此外，过度地烹饪食物，特别是蔬菜，会破坏维生素。所有这些都是我们在挑选食品和烹饪时应当予以特别注意的。