There is a very tight link between stress, depression, and obesity. It’s very difficult to determine whether the stress and depression are causing the obesity or whether the obesity is causing the stress and depression. It’s likely that both are occurring, creating a cycle of dangerous positive feedback. Stress and depression cause increasing obesity, which in turn, causes increased stress and depression.
The best way that I’m able to explain my opinions on this linkage is by evaluating our body’s response to stress in our modern environment and how it differs from the stress response that our ancestors required. For cavemen, acute stress was of primary concern. Our primal environment was ripe with thousands of potentially deadly encounters. There were no guardrails on the edge of the cliff and the mountain lions and grizzly bears were not penned up in a cage in the zoo. They roamed freely, possibly around the next bend. Our physiology is extremely effective at dealing with these acutely stressful threats. If you walk out of your cave and find yourself staring right into the eyes of a mountain lion, our stress response system will cause your pupils to dilate, your muscles will tighten, your heart will speed up, and you will be able to run faster, jump higher, and fight harder than you ever thought you could.
Fortunately, acute danger is relatively rare in our modern environment. However, financial concerns, marital strain, and stress in your workplace often pervade our daily life. We don’t have a separate system for dealing with chronically stressful situations, so we use the only one we have and try to approach our child’s bad report card the same way our ancestors dealt with dangerous mountain lions. The result is the over release of cortisol and several other chemicals that can shift our body toward fat storage.
Successful weight loss (with or without the use of surgery) is dependent on developing better methods of handling the chronic stress that all of us deal with. While there is no shortage of anti-depressants and anti-anxiety medications, they rarely result in significant improvements. On the other hand, exercise, meditation, and counselling are often truly helpful ways to reduce the amount of stress or sadness in life. Exploring all possible options is critical to ensure that we’ve done our best to reduce the weight gaining effects of untreated stress or depression.