Does what we eat affect our emotional state, and can dietary changes help prevent depression? Neuroscientist David Servan-Schreiber reflects on this.
I distinctly remember the contents of a lecture on nutrition that I listened to when I was in medical school. Its meaning boiled down to four points:
- overweight people should consume fewer calories;
- those suffering from cardiovascular diseases – less cholesterol;
- diabetics – less sugar;
- hypertension – less salt.
That’s all I got from that lecture.
When I later chose to specialize in neuropsychology, this issue was even simpler there: I did not hear a word about the relationship between nutrition and the risk of mental illness, including depression. It took me twenty years to discover that doctors like me knew far less about the connection between food and health than any reader of Psychologies. But in my practice, I often met patients like Robert, a fifty-year-old official from England.
Since childhood, he was lethargic, inactive, quickly tired, he had problems with concentration. He never felt able to “act quickly” and generally “be like others.” Robert had been living with a diagnosis of “chronic depression that could not be treated with medication” for a long time, when suddenly the doctor asked him how he eats.
Link between standard “Western” eating style and depression confirmed by scientific studies
Like most Englishmen, he ate mostly meat, cold cuts, white bread, pastries, sauces and dairy products. He liked deep-fried food and had a great weakness for a variety of sweets. Gradually, the doctor convinced him to switch to the so-called Mediterranean diet: eat more vegetables and fruits, less meat – preferably fish, as few sweets as possible …
And then one morning Robert woke up with the feeling that it was the first day of spring outside the window: the usual heaviness in his head disappeared, fatigue passed. He felt a lightness in his body, unfamiliar to him until now, and at the same time it seemed to him completely natural. I would not tell you this story if it was just one case or even ten. But the connection between the standard “Western” style of eating and depression has been confirmed by scientific studies.
Scientists from the French Institute of Health and Medical Research (Inserm), together with colleagues from the Department of Health at University College London, found that people who eat at least five years of “western style” increase their risk of depression by about 60%.
Perhaps this is because sugar, white flour and animal fats increase inflammation in the body and brain and this affects our neurons, thoughts and mood. In fact, it is not even that food can have such a tangible effect on the body and mind that is striking, but rather the fact that it had to wait until the end of 2009 for such a study to finally be published in a serious international medical journal!
In the future, we still have a lot of work to do, so that lectures on nutritionism – the doctrine of recovery through dietary changes – become part of medical education. And in the coming years, I’m afraid, Psychologies subscribers will still have to rely on their own reading preferences in this regard – they will help them turn the kitchen into a wellness workshop.