Treatments for depression and bipolar disorder may promote excessive meal and snack intake because will power seems to be inhibited.
Antidepressants and related medications are extremely useful for people experiencing a variety of mood disorders. Indeed, people are able to function at an optimal level when these drugs restore chemical balance in the brain. But as with most medications, there are side effects, and one of the most annoying caused by these drugs is weight gain.
Typically, the weight gain associated with antidepressant use ranges from 15 to 35 pounds, but people on drugs such as the ones used for bipolar disorder can gain 100 pounds or more. People taking such drugs report being unable to stop eating when they are full and occasionally will have a second large meal only an hour or so later after the first.
People usually lose interest in continuing to eat when they feel satiated or totally satisfied. The feeling is similar to that of not wanting to drink more water when the body has received enough fluid. In fact, if it is necessary to drink a large amount of water, for a medical test for example, it is very hard to do so after you stop feeling thirsty. The sensation of satiety is similar.
Even the most dedicated of eaters will stop and lose interest in food after feeling satisfied. This signal appears to be controlled by the brain chemical serotonin. It now appears that antidepressants, along with drugs for bipolar illness, undermine serotonin’s ability to release the signal that indicates eating should stop. How these drugs do this is still not well understood, especially as they are able to make serotonin’s other function – improving mood – much more effective.
Not feeling satiated can seriously weaken will power. Will power is used to stop yourself from eating tempting but unnecessary food, especially if you have just eaten a meal. Will power keeps you, at least some of the time, from snacking on an ice cream cone because someone else is eating one, or buying a slice of pizza when you smell the melted cheese and spices. Will power allows you to say no to dessert when you are feeling quite full, even though the dessert menu seems irresistible.
But antidepressants and drugs for bipolar disorder weaken will power by taking away that feeling of satiation. An individual on these drugs doesn’t lose the desire to continuing eating even if the stomach is stuffed. So second helpings, desserts and snacks are eaten regardless of calorie content or how much food has been consumed only a short while earlier. This accounts for the often very rapid weight gain associated with these medications.
So far there seems to be little help for people whose weight has increased and will power decreased because of these medications. Indeed, it is not unusual for people to consider going off medication in order to lose weight.
The most effective and actually simplest solution to this problem is to increase the power of satiety. When the feeling of “I really don’t want to put any more food in my mouth” is experienced, it doesn’t take any will power to stop eating.
Several years ago a study at a Harvard University-associated psychiatric hospital was carried out with patients who had gained weight on drugs from mood disorders. The intervention was not only simple, it tasted good. Patients were put on a weight-loss program that had them drinking a carbohydrate-based beverage to increase the amount of serotonin in their brain. For at least 30 years it has been known that the brain makes serotonin only when carbohydrates are eaten. So the study tested whether it would be easy to follow a diet plan if serotonin was increased and the signal to stop eating became stronger. The study worked.
Patients felt full and often complained that there were given too much food to eat. Best of all, they lost weight. Some switched to carbohydrate snacks like popcorn or pretzels rather than the drink but regardless of whether the carbs were drunk or chewed, the effect was the same. When serotonin went up, weight went down.