Myth Busters: The Stress and Nutrition Edition

shutterstock_90278629Whether from friends, family members, or patients, we’ve all heard it before: “It’s so frustrating that I keep gaining weight, but I’ve just been so stressed out lately!” Upon hearing this, do you ever wonder if simply being stressed can actually lead to weight gain? Have you ever questioned if there is actually such a thing as stress-inducing foods?

Before answering these questions, it is important to understand that stress is not just an emotion; it is a physiologic reaction to anything that overwhelms or threatens the body’s ability to maintain homeostasis. There are various types of stressors, ranging from physical (i.e. surgery) to chemical (i.e. reduced oxygen supply) to social (i.e. personal conflicts or major life changes), and not all of these stressors are created equal. While some occur repeatedly, leading to chronic stress, others elicit an acute stress response.

The acute stress response is also known as the Sympathetic Adrenal Medullary (SAM) System, or “fight-or-flight” response. Its main end products are epinephrine and norepinephrine, which, in addition to increasing heart and respiratory rates, decrease appetite. The theory is that once upon a time, when encountering dangerous situations, the body could not afford to expend energy digesting food because it needed to divert all of its energy to “fighting or fleeing.”

However, when people talk about being stressed out, they are likely not referring to things that would activate the acute stress response. Instead, daily stressors activate the chronic stress response, also known as the Hypothalamic-Pituitary-Adrenal (HPA) Axis. The end product of this system is cortisol, which is the hormone most people think of when they hear the word “stress.” Not only does cortisol stimulate appetite, but it also leads to preference of hyperpalatable foods. Moreover, cortisol inhibits insulin release and blocks the migration of GLUT4 glucose receptors to cells’ surfaces. Thus, when cortisol is released, our appetite increases while insulin release decreases, meaning the glucose we consume cannot properly enter our cells. Therefore, despite adequate energy intake, our cells think we are starving, which further stimulates appetite and perpetuates the issue.

But what about the reverse relationship? Can consuming certain foods make us more stressed? In general, it’s not that simple. Most foods that are touted as stress-inducing demons have not actually been studied by reputable researchers, and those that have been studied haven’t produced enough solid evidence to warrant us warning our patients about them. Here are a few of the foods that have been studied recently and the results of these studies:

  • Caffeine: Research shows that caffeine can keep cortisol levels from falling, but this does not prove a causal relationship between caffeine and stress.
  • Alcohol: About 3 well-defined studies have come to the same conclusion: Heavy drinking does lead to increased cortisol output. Again, this does not prove a causal relationship.
  • Sugar: Evidence is very weak that consuming sugary foods actually causes stress.

So what are the takeaway points from all of this when it comes to intelligently discussing stress and nutrition with our patients?
Chronic stress can in fact lead to increased appetite, but we must recognize that mental health is not our area of expertise as dietitians. Encourage patients to seek out help from a psychologist or psychiatrist as necessary. It may be appropriate to explain that working to control one’s stress may aid in the weight loss process.

  1. Encourage patients to pay attention to hunger and satiety cues. Explain the concept of emotional eating and teach them to pay attention to whether they are eating because they are hungry or because they are stressed or bored.
  2. Research has not yet shown us that there are foods that cause stress. Continue to teach patients about consuming a balanced diet full of fruits, vegetables, and whole grains.

And most importantly… The relationship between stress and weight gain is correlational, not causal! There are many other factors affecting weight gain and loss. Emphasize to patients that in the face of stress, there are still other things they can be doing to work towards weight loss. They are not helpless.

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Diana Gulotta is a Dietetic Intern at the University of Virginia Health System in Charlottesville, VA. A Wisconsin native (Go Pack Go!), Diana graduated with Highest Distinction from the University of Wisconsin-Madison in 2015 with a degree in Dietetics. In her free time, Diana enjoys singing, hiking, cooking, and reading.