The physiological state which decreases appetite and indicates the feeling of fullness is known as _______. 

The correct answer is satiety.

Key Points

• Satiety is the physiological state of feeling full or satisfied, leading to a decreased desire to eat.
• It is regulated by complex interactions between the gastrointestinal tract, the brain, and hormones such as leptin and ghrelin.
• Satiety is critical for maintaining energy balance and preventing overeating, contributing to healthy body weight.
• Foods rich in fiber, protein, and healthy fats are known to enhance satiety by slowing digestion and promoting prolonged feelings of fullness.
• The hypothalamus, a part of the brain, plays a central role in integrating signals related to hunger and satiety.

Additional Information

• Leptin
  • A hormone produced by fat cells (adipocytes) that signals the brain to reduce appetite and increase energy expenditure.
  • Leptin resistance, often seen in obesity, can impair satiety signals and lead to overeating.
• Ghrelin
  • Known as the "hunger hormone," ghrelin is secreted by the stomach when it is empty to stimulate appetite.
  • Levels of ghrelin decrease after eating, contributing to feelings of satiety.
• Hypothalamus
  • A region of the brain responsible for regulating hunger and satiety through neural and hormonal signals.
  • It integrates information from hormones like leptin, ghrelin, insulin, and peptide YY to maintain energy homeostasis.
• Role of Fiber in Satiety
  • Dietary fiber slows gastric emptying, prolonging the digestion process and promoting feelings of fullness.
  • High-fiber foods like vegetables, fruits, and whole grains are often recommended for weight management.
• Satiety vs. Hunger
  • Hunger is the physiological need for food, driven by energy deficits, while satiety is the state of being satisfied after eating.
  • Both states are essential for energy regulation and are influenced by a variety of internal and external factors.