Hypothalamic Obesity (HyOb)

The hypothalamus is a tiny part of the brain that controls messages among the gut, fat cells and the brain. It tells us when we are hungry and when we have had enough to eat. 

Hypothalamic obesity (HyOb) is a complicated medical condition that can occur from the growth of rare brain tumors and from other types of injury to the hypothalamus. Craniopharyngioma (krā'nē-ō-fə-rĭn'jē-ō'ma) is one of the tumors that can cause HyOb. 

When there is damage to the hypothalamus, the communication between the gut and the brain goes haywire, causing a constant feeling of hunger.   

Since the hypothalamus cannot “hear” the signal that comes from the fat that is supposed to tell the hypothalamus to turn off hunger, the person continues to feel hungry.  He or she will continue to eat excessively,  the extra calories eaten are stored as fat, and the person never feels full. This can cause 1-2 pounds of weight gain a week.  

As more and more weight is gained, the body begins to store fat in places that are harmful to health such as in the muscles, liver and in and around other important organs in the belly. This can make it difficult for these important organs to function.

Interventions for weight loss are essential in such patients.

In addition to the feeling of non-stop hunger, the person may feel irritable because there is extra insulin production. 

Some medications have been used with some measures of success with hypothalamic obesity. 

Gastric bypass surgery has also been found to help with weight loss and controlling hunger in people with hypothalamic obesity.  

After surgery, the person has weight loss, less insulin production and the constant feelings of hunger are under better control.

Bariatric surgery is not the best option for everyone.  It is recommended only after all other weight-loss measures have failed.

Last Updated 03/2014