Obesity Causes Hunger

The feeling of hunger is universal: Everyone can identify the effects of hunger. Few people wonder what causes hunger because the answer seems obvious: You experience hunger when you’re hungry. However, this answer doesn’t actually explain much. Certainly, people feel hunger when they need to eat, but other factors affect hunger symptoms.

The Effects of Hunger

Physical hunger manifests in several ways. The stomach contracts, causing what are popularly known as “hunger pains.” Hunger pains include both pangs and a hollow feeling. The stomach may also growl or rumble.

The effects of hunger extend to the brain. As the brain receives signals that the stomach is empty, people may experience irritability and headaches or find it difficult to concentrate. When lack of food depletes energy reserves, people may become lightheaded, dizzy or fatigued.

Causes of Hunger: Hormones

Hunger is directly tied to appetite, which is controlled by hormones. The hormone ghrelin, which stimulates appetite, rises before eating. Leptin, in contrast, is an appetite-suppressing hormone. Paradoxically, people suffering from obesity have lower than normal levels of ghrelin and high levels of leptin. This suggests that obese people may be resistant to leptin’s appetite suppressing effects, resulting in constant hunger.

Psychological Causes of Hunger

Psychological causes of hunger have little to do with physical hunger — a person can experience psychological hunger on a full stomach. Psychological hunger can be triggered by the smell or sight of a favorite food. The food does not have to be physically present: A television commercial or picture can be enough to trigger a craving.

Associating eating with certain activities can trigger psychological hunger. For instance, many people snack while watching television. The brain associates the two activities, so the act of watching television can trigger feelings of hunger.

Emotional eating occurs when people eat to deal with stress or upsetting emotions. The emotion triggers hunger and the urge to eat, which provides temporary comfort and relief. The association of emotions and food is a common cause of overeating.

Constant Hunger and Excessive Hunger Causes

Constant hunger can be a sign of a medical disorder. Excessive hunger causes may include:

  • Anxiety
  • Bipolar disorder
  • Brain injuries
  • Depression
  • Diabetes
  • Hyperthyroidism
  • Tapeworms or other parasites.

Constant hunger can also indicate the presence of eating disorders such as binge eating and bulimia nervosa. If you are experiencing the effects of hunger, despite eating enough, speak with your doctor to determine what is causing your excessive hunger.


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