When it comes to digestion, chewing is only half the battle. As food travels from your mouth into your digestive system, it’s broken down by消化酶这将其变成较小的营养素，您的身体很容易吸收。
这种分解称为化学消化。没有它，您的身体将无法从吃的食物中吸收营养。
继续阅读以了解有关化学消化的更多信息，包括它与机械消化有何不同。
Chemical and mechanical digestion are the two methods your body uses to break down foods. Mechanical digestion involves physical movement to make foods smaller. Chemical digestion uses enzymes to break down food.
机械消化
机械消化始于您的口腔，然后咀嚼，然后移动到胃中搅动并在小肠中进行分割。蠕动也是机械消化的一部分。这是指食道，胃和肠道肌肉的非自愿收缩和放松，以分解食物并通过消化系统将其移动。
化学消化
化学消化涉及整个消化道的分泌物。这些酶破坏了将食物颗粒固定在一起的化学键。这样可以将食物分解成小的，消化不良的部分。
How they work together
Once food particles reach your small intestine, the intestines continue to move. This helps keep food particles moving and exposes more of them to digestive enzymes. These movements also help to move the digested food toward the large intestine for eventual excretion.
消化涉及将大部分食物分解成小的微量营养素，足以被细胞吸收。咀嚼和蠕动为此提供帮助，但它们不会使颗粒足够小。那就是化学消化的地方。
化学消化breaks down different nutrients, such as proteins, carbohydrates, and fats, into even smaller parts:
- Fatsbreak down into fatty acids and monoglycerides.
- Nucleic acidsbreak down into nucleotides.
- 多糖或碳水化合物糖，分解成单糖。
- 蛋白质break down into amino acids.
没有化学消化，您的身体将无法吸收营养，从而导致维生素缺乏症和营养不良.
有些人可能缺乏化学消化中使用的某些酶。例如，有lactose intolerance通常不会生产足够的乳糖酶，即促进乳糖的酶，这是在牛奶中发现的蛋白质。
化学消化从您的口中开始。咀嚼时，唾液腺释放出唾液进入您的嘴。唾液含有从化学消化过程开始的消化酶。
口腔中发现的消化酶包括：
- 舌脂肪酶。This enzyme breaks down triglycerides, a kind of fat.
- Salivary amylase.这种酶分解了多糖，这是一种复杂的糖，是碳水化合物。
化学消化不仅仅是嘴里的酶停止。
Here’s a look at some of the main stops on the digestive system involving chemical digestion:
Stomach
在你的胃, unique chief cells secrete digestive enzymes. One is pepsin, which breaks down proteins. Another is gastric lipase, which breaks down triglycerides. In your stomach, your body absorbs fat-soluble substances, such as aspirin and alcohol.
Small intestine
Thesmall intestineis a major site for chemical digestion and absorption of key food components, such as amino acids, peptides, and glucose for energy. There are lots of enzymes released in the small intestine and from the nearby pancreas for digestion. These include lactase to digest lactose and sucrase to digest sucrose, or sugar.
Large intestine
大肠不会释放消化酶，但确实含有进一步分解营养素的细菌。它还吸收维生素，矿物质和水。
化学消化is a vital part of the digestive process. Without it, your body wouldn’t be able to absorb nutrients from the foods you eat. While mechanical digestion involves physical movements, such as chewing and muscle contractions, chemical digestion uses enzymes to break down food.
