Carbohydrate consists of three elements: carbon, hydrogen and oxygen. Because the ratio of hydrogen to oxygen is two to one, which is the same as water, it is called carbohydrate. It is the cheapest of the three main nutrients that provide heat energy for human body. Carbohydrates in food can be divided into two categories: effective carbohydrates that people can absorb and utilize, such as monosaccharides, disaccharides, polysaccharides and ineffective carbohydrates that people can't digest, such as cellulose.
First, the main physiological functions of carbohydrates
1, an important substance that constitutes the body;
2. provide heat energy;
3. Adjust the taste of food;
4. Energy necessary to maintain brain function;
5. Regulate fat metabolism;
6. Provide dietary fiber;
Second, carbohydrates and health.
Lack of carbohydrate in diet can lead to general weakness, fatigue, decreased blood sugar content, dizziness, palpitation, brain dysfunction and so on. Severe cases can lead to hypoglycemia coma.
When there are too many carbohydrates in the diet, they will be converted into fat and stored in the body, which will make people too obese and lead to various diseases such as hyperlipidemia and diabetes.
Third, the recommended daily intake of carbohydrates and their food sources.
Generally speaking, carbohydrates have no specific dietary requirements. It is mainly to obtain a reasonable proportion of calorie intake from carbohydrates. In addition, at least 50 ~100g of digestible carbohydrates should be ingested every day to prevent carbohydrate deficiency.
The main food sources of carbohydrates are: sucrose, grains (such as rice, wheat, corn, barley, oats, sorghum, etc. ), fruits (such as sugar cane, melon, watermelon, banana, grape, etc. ), nuts and vegetables (such as carrots and sweet potatoes). ).