Sugar - Eat for Health - Easily Understand Nutrients 1

Author: Wang Qianghu
Publisher:
Publish Date: 2006-06-01
Features: What is sugar? Some people might think it's strange to ask such a question. In fact, what most people understand as sugar is quite different from what nutrition science defines as sugar. Specifically, the concept of sugar can be broadly and narrowly defined. Broadly, sugar refers to all digestible carbohydrates, including sweet sugars and non-sweet starches. Foods like steamed buns, rice, and bread that we commonly eat fall under the category of broad sugar substances. Narrowly, sugar refers to refined white sugar, brown sugar, rock sugar, and syrup. In nutrition, broad sugar, along with proteins and fats, is collectively known as the three major nutrients for the human body. Although sugar accounts for only about 2% of the human body's weight, it is the primary energy source. Under normal physiological conditions, about 70% of the energy the body needs is provided by sugar. Structurally, carbohydrates are composed of carbon, hydrogen, and oxygen, with a hydrogen-oxygen ratio of 2:1, similar to water. Therefore, carbohydrates are also referred to as "carbohydrazes." Carbohydrates are divided into monosaccharides, disaccharides (such as sucrose, maltose, and lactose), and polysaccharides (such as starch, glycogen, and cellulose) based on their hydrolysis results. Starch in rice, wheat, corn, and sweet potatoes is a polysaccharide; polysaccharides are composed of hundreds or even tens of thousands of monosaccharide units. The starch ingested by the human body must undergo multiple steps to be digested, broken down, and absorbed. Since the human body lacks the enzyme to hydrolyze cellulose, humans cannot utilize cellulose as a nutrient. The sucrose in brown sugar and white sugar, as well as lactose in milk, are disaccharides. The sugar in fruits is mainly glucose and fructose, which are monosaccharides. Monosaccharides and disaccharides are easily absorbed by the human body. Monosaccharides and disaccharides are sweet, while polysaccharides are not.