It’s amazing how easily some health concepts are accepted as gospel while others aren’t. Some ideas just seem to catch our imaginations and hold on. Others never make it into the collective consciousness no matter how strong the evidence.
The idea of depression as a “chemical imbalance” is one of the ideas we’ve latched onto in spite of the lack of evidence. In fact, since we’ve been able to actually measure the levels of chemicals in the brain, the evidence strongly suggests that depression has nothing to do with brain chemicals. Or at least not the brain chemicals that antidepressants affect.
Of course that hasn’t stopped Big Pharma from coming out with new drugs to treat this theoretical imbalance. Neither has the fact that antidepressants are no more effective than placebos. The idea of depression as a physical problem — a chemical deficiency — has taken root and we're not going to let go of it.
As the years have gone by and the “chemical imbalance” mantra has become entrenched, we’ve divided depression into more and more categories. One of the most well-known to the general public is so-called Seasonal Affective Disorder, or SAD.
The idea of SAD arose in the ‘80s, and it’s been selling antidepressants and special “light therapy devices” ever since. But there’s bad news for Big Pharma: a recent, massive study says that there’s really no such thing as SAD.
All aboard the “Winter Blues” train
It’s been accepted without question for years, just like the “chemical imbalance” craze: winter causes depression in many people. The dogma is that the shorter, darker days of winter bring on depression and that it disappears in spring or early summer as the days lengthen.
It sounds logical. The theory is that the lack of sunlight during the winter leads to low serotonin levels and high melatonin. Serotonin is the chemical whose lack we’ve been told causes depression. Melatonin is the chemical which makes us sleepy.
The treatment — surprise! — has been antidepressants. Specifically, Selective Serotonin Reuptake Inhibitor or SSRI antidepressants, which increase the amount of serotonin in the brain. And even more specifically, fluoxetine, brand-named Prozac.
A slightly newer and purportedly more effective treatment is a special device called a lightbox. This is just what it sounds like: a box with a light in it. The light is a special full-spectrum light that mimics natural light (without the UV rays.) You sit in front of the light for an hour or two per day. The exposure to “natural” light raises your serotonin levels and lowers your melatonin, theoretically curing your SAD.
According to the Mayo Clinic, the symptoms of SAD are these:
- Tiredness or low energy.
- Problems getting along with other people.
- Hypersensitivity to rejection.
- Heavy feeling in the arms or legs. Oversleeping.
- Appetite changes, especially a craving for foods high in carbohydrates.
- Weight gain.
If this sounds like typical human winter feelings and behavior, you’re not alone. Through the years there have been plenty of people who questioned whether SAD was a legitimate psychiatric problem. And recently, scientists decided to put the idea to the test.
A sad ending for the concept of SAD
Researchers at Auburn University decided to find out once and for all if winter really brings on depression. They ran a huge study involving over thirty-four thousand people. The results, published in Clinical Psychological Science, ought to put a dent in winter Prozac sales, but I’m not holding my breath. They found that winter unequivocally did not make people depressed. The results were so clear that researchers called SAD a “well-intentioned folk theory.”
The study had people fill out a depression symptom questionnaire at various times of year. They looked at the responses as a whole. They looked at responses from only the people who reported being depressed. But no matter how they looked at them there was no link between depression and winter — or any other time of year.
Take that, Big Pharma.
The Auburn scientists say that the original studies on SAD were fatally flawed. Unbelievably, they only looked at people who said they had mood changes during winter. That’s a bit like running a study on whether more people like Coke or Pepsi, then only including Coke drinkers. Of course you’re going to get the results you want. What are the odds that the original studies, the ones that put SAD out there as a diagnosis in the first place, were funded by Big Pharma?
I’d say they’re pretty good.
Of course this isn’t the final word on SAD. It’s been part of our mythology for too long, just like the “chemical imbalance” theory. We’re not going to let go of it easily. But it may help to put our minds at ease somewhat. If you’re irritable and craving carbs in the winter, you don’t necessarily have SAD. You might just be feeling the stress of the holidays.
The symptoms of depression go deeper than that, and they’re not something to ignore. If you’re feeling hopeless and worthless on a regular basis, or if you’re sad most of the time, it may be time to talk to someone. If you’re tired and grumpy and you tend to oversleep, it’s probably just time to adjust your lifestyle to fit the season.