I hear this question frequently from my patients, and the simple answer is, yes, stress can contribute to weight gain. The more complicated questions: HOW does stress make us fat, and what can we do about it?
We've long known that stress can make us eat more - but now it appears that stress can actually slow down our metabolism. New research from Wexner Medical Center at Ohio State University suggests there are multiple 'mechanisms' or ways that stress can contribute to weight gain. Their study showed that women who were under stress actually burned fewer calories than women who were not stressed - 104 calories less, enough to cause 11 pounds of weight gain a year. Eleven pounds per year - and that's just the metabolic effect alone, if the women did not also eat extra calories (and we know that people who are stressed also tend to eat more calories, and are drawn to eat sugary/fatty foods.) If they ate more calories too, the weight gain could be much greater. http://www.biologicalpsychiatryjournal.com/article/S0006-3223%2814%2900385-0/abstract
A key point is that the women in the study had not eaten more - the food was controlled, so that was not a factor, not a cause of the lower metabolism. It was the stress that changed the body chemistry. The women were given identical high fat meals. In addition to slower metabolic rates, the women also had higher levels of insulin in their blood after the meals. Earlier research shows a similar effect in men.
In addition to the metabolic effect, we know that stress can lead to 'emotional eating' - and we can end up eating larger quantities of food, and reach for poor quality 'junk food' which has hundreds of empty calories in just a few bites. Junk food tends to have high glycemic index carbohydrates and copious amounts of saturated fat - which can make us feel better in the moment, but much worse a while later, both mentally and physically. These 'hyper-palatable'/super-tasty foods can cause a flood of 'happy hormones' (dopamine in particular) in our hypothalamus, the reward center of the brain. But the effect soon wears off, and we can feel even worse than when we started. Excess saturated fat also can lead to inflammation and insulin resistance, with multiple negative effects on our health.
So, what to do? Ideally we would reduce unhealthy stress in our lives, but that can be easier said than done! We can improve our ability to cope with stress by taking care of ourselves with the following strategies:
1) Get adequate sleep (sleep can clear out or 'defrag' the brain, and help us feel stronger, more resilient.) We need to employ 'sleep hygiene', which means keeping our bedrooms cool, dark, and quiet (or have 'white noise' or gentle music playing.) Try to avoid screen time before bed, since blue light disrupts sleep quality, and stimulates wakefulness. Many people thrive with 7 or 8 hours of good quality sleep. http://www.health.harvard.edu/newsletters/Harvard_Health_Letter/2012/May/blue-light-has-a-dark-side/
2) Get daily exercise (which can raise serotonin levels naturally, and can help us cope with stress.) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2077351/
3) Surround ourselves with healthy food options, so the 'easy choice is the healthy choice'. At the end of a stressful day, our willpower reserves are depleted, and we naturally reach for what is easiest. There is a lot of new research about 'decision fatigue' - the fact that when we are exhausted from making too many decisions, that we have little energy left to make healthy choices. As one patient said, "we eat what is there, and we do what is easiest" - so it's a smart strategy to acknowledge this aspect of human nature, and work WITH it, not try to fight it. Supermarkets know we'll reach for what is at eye level - so use this strategy at home, and at work. Keep the healthy foods front and center, make them 'easy to choose.' Remove tempting 'junk food' from our immediate view (ideally remove from our environment, but at the very least, HIDE it.) Make it harder to access the 'junk', and remember, if it's not there, you can't eat it. http://www.nytimes.com/2011/08/21/magazine/do-you-suffer-from-decision-fatigue.html?pagewanted=all
4) Start to explore other options for relaxation, such as meditation, or 'Japanese Forest Bathing' (basically walking in nature as a way to decrease stress.) http://www.shinrin-yoku.org/research.html Research has shown that both traditional mediation and 'walking meditation' can be calming. Many of us need more time alone, to decompress; we need to take care of our 'inner introvert'. I'll write more on this subject, but the topic of 'unmet needs' is a major factor contributing to excess weight and poor health in our country. We all have needs for things such as: time alone, time socializing, spirituality, creativity, etc. We can begin to explore our unmet needs by ourselves, during quiet walks, or with help from a good friend or counselor - or even your favorite nutritionist or Obesity Medicine physician!