肠道细菌利用复杂的碳水化合物调节宿主食物偏好

Carbohydrates, proteins, and fats are the primary macronutrients in the human diet. However, carbohydrates are the most favored source of energy in the body. They can be found in a wide variety of foods, including whole grains, fruit, and vegetables, in various forms, such as sugars, starch, and dietary fiber. Based on their structure, carbohydrates are classified into three main classes— monosaccharides, disaccharides, and polysaccharides. The body's cells can only utilize simple...

Carbohydrates are polymers composed of molecules containing atoms of carbon, hydrogen and oxygen. One gram of carbohydrate can provide four kilo-calories of energy, which makes it the most efficient instant energy source.
Starch accounts for approximately 60% of the carbohydrates consumed by humans. Since amylase enzymes cannot function in the stomach's acidic environment, starch can only be digested in the mouth and small intestine. Simple sugars are found naturally in milk and fruits in...

The gut microbiome is formed by a vast and diverse community of bacteria that colonizes our large intestine. These bacteria start residing in the gut from birth and continue diversifying throughout life, influenced by factors such as diet, lifestyle, and stress. The gut bacterial community also includes bacteria from food and those that enter the colon through the anus.
The normal gut flora of the colon plays a critical role in generating essential vitamins such as vitamins K, B5, and B7.

Carbohydrate digestion and metabolism break down simple and complex carbohydrates from food into saccharides (i.e., sugars) for the body to use as energy. Carbohydrate digestion starts in the mouth during mastication, or chewing. The masticated carbohydrates remain intact in the stomach. Digestion resumes in the duodenum of the small intestine, where pancreatic alpha-amylase and brush border enzymes of the microvilli convert complex carbohydrates to monosaccharides. Finally, the monosaccharides...

Carbohydrates are predominantly obtained from plant sources. With the exception of lactose found in milk and insignificant glycogen amounts in meat, most consumed carbohydrates have plant origins. Monosaccharides and disaccharides, or sugars, can be sourced from fruits, honey, milk, sugar cane, and sugar beets. Grains and vegetables are rich in the polysaccharide starch. Two types of polysaccharides provide fiber: cellulose, which is abundant in many vegetables, forms undigestible roughage or...

Carbohydrates are essential macronutrients that serve as the body's primary energy source. Their digestion begins in the mouth, where salivary amylase partially breaks down complex carbohydrates such as starch into smaller oligosaccharides. This mechanical and enzymatic activity prepares carbohydrates for further processing in the gastrointestinal tract.
After being swallowed, the partially digested carbohydrates mix with gastric secretions in the stomach. However, the acidic environment...