Self medicating for mood disorders is well known. It is often quite harmful, with the chief culprits being ethyl alcohol and nicotine. But there are others. One that comes up often is chocolate as an antidote to feelings of depression. Not everyone who eats chocolate is depressed, of course. Probably most of us who do it do it because we like chocolate. When I was in elementary school I used to eat a lot of Hershey bars after school. They cam in six-packs and one memorable day I found two whole packs and one pack with a single bar missing. I ate all 17 in one sitting. Two hours later I ate dinner. I couldn’t do that again, both because I would gain weight with the speed of light (I still have a BMI under 25 but I’m pushing it) and because I wouldn’t have any appetite for dinner. Nor would it make me feel better. Probably just sick to my stomach.
But a lot of people do report that they crave chocolate when they are feeling down, so a recent article in Archives of Internal Medicine tested the proposition that this was a case of self medicating:
People battling signs of major depression showed a yearning for chocolate that drove them to eat twice as much of the sweet treat as those not depressed, University of California researchers said.
Adults with symptoms of severe depression gobbled an average of 11.8 one-ounce servings a month, according to the study. That?s comparable to about six dozen Hershey?s Kisses monthly. Individuals not depressed ate 5.4 one-ounce servings, and those who showed possible signs of the condition nibbled 8.4, the scientists said. Men consumed almost as much chocolate as women, according to data on more than 900 adults. (Nicole Ostrow, Bloomberg)
By the standards of someone who ate 17 Hersey bars in one sitting, 6 dozen chocolate kisses doesn’t sound like a lot, but it is clear that people who answered a general questionnaire about diet (including chocolate consumption) and a set of questions to evaluate depressive affect ate considerably more chocolate than others. Using a common scale, the Center for Epidemiological Studies-Depression Scale (CES-D) that has been widely used and validated. The Results, from the Abstract of the paper:
Those screening positive for possible depression (CES-D score 16) had higher chocolate consumption (8.4 servings per month) than those not screening positive (5.4 servings per month) (P = .004); those with still higher CES-D scores (22) had still higher chocolate consumption (11.8 servings per month) (P value for trend, <.01). These associations extended to both men and women. These findings did not appear to be explained by a general increase in fat, carbohydrate, or energy intake. (Chocolate and Depressive Symptoms in a Cross-sectional Analysis, Natalie Rose, MD; Sabrina Koperski, BS; Beatrice A. Golomb, MD, PhD, Arch Intern Med. 2010;170(8):699-703.
Here’s a bar graph that shows the data, which are fairly impressive looking in this form:
What this study showed is that the difference in chocolate consumption was not explained by a number of other possible mood-related dietary items like sugar, caffeine and fat. On the other hand, it is possible that the higher CES-D respondents were different in other ways that were reflected in chocolate consumption.
On the basis of this study, if chocolate consumption is truly a form of self medication, like other examples it doesn’t do the trick. That’s not unusual. Just because your body is telling you to do something, doesn’t mean that it knows what it’s talking about.
Meanwhile I will go on eating chocolate without worrying that it’s a sign of depression. Sometimes a kiss is just a kiss.