A few days ago, a client asked me how she could tell when she was hungry. “I know what it is like to be thirsty,” she said. “But I am not sure I can tell the difference between being hungry and just wanting to eat. After I started on antidepressants I found myself putting food in my mouth even though I don’t think I should be eating.”
I told her that she had pinpointed one of the biggest problems facing people on medications like hers, along with anyone concerned about weight. We seem to get many signals from our body telling us to eat. Sometimes it is real hunger but often it is what I call appetite.
As I explained to her, hunger feels urgent. There is a need to eat right now and just about anything will do. Perhaps the best example comes from Genesis when Esau, the twin brother of Jacob, comes in from working in the field claiming that he will die if he doesn’t get something to eat. The urgency and need are so great, he is willing to forfeit his birthright as the first-born twin to get a pot of lentil stew.
Fortunately, most of us will never find ourselves so hungry that we are willing to sacrifice something precious for food. A more practical test is to ask yourself whether you are hungry enough to eat a food that you really don’t like that much. It doesn’t have to be broiled rattlesnake or moldy bread. But as I told the client, think of some foods that don’t appeal. "Plain unsalted rice cakes "she quickly answered. “Especially after they get soft. It is like chewing through a dry sponge.”
" O.K.," I replied. “Do this test. Tomorrow, when you are thinking about eating, ask yourself whether you are hungry enough to eat some soggy rice cakes. Don’t eat them. Just see whether you would be willing to eat them.”
She laughed and told me she would try the experiment.
When I saw her a week later, she told me the experiment had worked. “I probably felt like putting something in my mouth a dozen times during the day and evening,” she reported. "But when I considered that old rice cake, that desire just vanished-except at meals. So I knew I was hungry at mealtime. "
“But everyday around 4pm something strange happened. I wasn’t really hungry but the idea of eating something starchy appealed to me. And I was willing to consider those rice cakes. What was that all about?”
“The 4 pm need to eat,” I explained, "is a special kind of hunger. It comes from the brain, not the stomach. It is a signal that the brain needs to make serotonin.
"Serotonin is manufactured only after sweet or starchy carbohydrates are eaten and without any protein. Moods seem to dip late in the afternoon and our research indicates that low serotonin is behind this mood change. So the hunger you felt, even for rice cakes, came from the brain. If you eat a small amount of sweet or starchy food, the carbohydrate hunger will go away. But people who are on antidepressants sometimes find that this need to eat carbohydrate persists, even after 4 pm. It may be because the antidepressants prevent serotonin from making the hunger go away. Try eating only starchy carbohydrates and vegetables for dinner. That way your brain will be making serotonin through the evening and prevent your from having the evening munchies.
" By the way,you don’t have to eat soggy rice cakes for snacks," I added. “Crisp ones with a small amount of jam makes a great serotonin-boosting snack. And there are lots of other fat-free or carb snacks you can eat, like cold cereal, pretzels, popcorn, granola bars, soy crackers, fat-free frozen yogurt-even Twizzlers. And your brain won’t mind if they taste good.”