hungry

Hunger is the physiological and psychological sensation of needing or wanting to eat, arising from an energy deficit in the body. In everyday use, hunger refers to the urge to eat, while appetite denotes the desire for food that can occur even with adequate energy reserves. Hunger can be triggered by skipped meals, physical activity, or signals of low energy.

Physiologically, hunger involves signals from the gastrointestinal tract and hormones. The stomach releases ghrelin, which acts on the brain to stimulate appetite. The hypothalamus integrates ghrelin, leptin, insulin, and other signals to regulate hunger and satiety. Stomach contractions, or hunger pangs, may accompany the sensation.

Symptoms of hunger include stomach growling, weakness, lightheadedness, irritability, and difficulty concentrating. In healthy individuals, hunger cycles align with meal timing and energy expenditure. Appetite, mood, stress, and cultural norms can modulate the subjective experience of hunger.

In broader contexts, chronic or extreme hunger is associated with malnutrition or food insecurity, where reliable access to sufficient and nutritious food is limited. Hunger is not only a physiological state but also a social issue, influencing behavior, health, and policy.

Etymology: hunger derives from Old English hungor, related to German Hunger and Dutch honger; cognate with Proto-Germanic terms.

See also: appetite, satiety, hunger pang, malnutrition, food insecurity.