The Big Connection Between Stress and Weight Gain

Aug 24, 2023

1. Apart from stress eating, what mechanisms in the body might come into play when it comes to stress?

Stress triggers our brain to tell us to overeat, and not broccoli and carrots – junk food. However, in addition to that, stress can have negative effects on our body outside of out tendency to overeat. The culprit? Cortisol. Cortisol is commonly known as the fight or flight hormone and is secreted in the body in reaction to perceived stress. One of its functions is to shuttle glucose out of storage and prepare you for the ensuing battle your brain and body think you are about to have. The problem is that under chronic stress (the type of stress that endures for long periods of time), the body does not need the extra glucose being shuttled out and we are left with too much glucose, which in turn triggers the release of insulin. Chronically elevated levels of cortisol lead to increased levels of insulin which leads to weight gain and obesity, according to Dr. Jason Fung in his well-known book The Obesity Code. In short, cortisol can cause weight gain. Not just from overeating, but due to the chronic secretion of the hormone itself. You can read more about some of the studies that show the relationship between cortisol and obesity here, here and here

2. How would those have a possible effect on someone’s weight (as well as their psychological reaction to weight gain)?

(Effect on weight addressed above). 

The psychological effects of this can be frustrating and can contribute to the negative cycle. Once there is a chronic level of cortisol secreted no amount of exercise or calorie restriction will budge someone’s weight. In other words, if you have elevated cortisol levels, you can’t lose weight no matter what you try1. Imagine eating well, exercising and doing everything you can think of to stay healthy, only to find you’re gaining weight – seemingly out of your control. This, then, leads to feelings of distress (contributing to the stress levels and cortisol secretion) and the cycle continues. 

3. For someone who struggles with weight loss or maintenance, are there first-step strategies for controlling stress that tend to be helpful?

Mindfulness is the best first line of defense. Mindfulness has been show to have the following benefits (just to name a few). 

  • Increase our ability to regulate our emotions
  • Foster positive thoughts and emotions
  • Increase happiness and improve mood
  • Shield us from stress and emotional eating
  • Decrease anxiety, anger, depression and fatigue
  • Decrease negative thinking and avoidance behaviors

One study, conducted at Harvard University, found the area of the brain involved in emotion regulation called the insula grew stronger in people who practiced mindfulness. Another study, conducted at the University of Pittsburgh, found that practicing mindfulness thickens the prefrontal cortex, the area of the brain that controls the high-level skills known as executive function, and shrinks the amygdala, the area of the brain that initiates stress. In short, mindfulness can protect you against stress and help you make better decisions. 

Exercise is another way you can reduce stress. Exercise reduces your adrenaline and cortisol hormones (stress hormones), but it stimulates your endorphins (mood elevators and natural painkillers). All exercise does these two things, but walking in nature has been shown to have psychological benefits– walking as opposed to high intensity power walking, running, or other high intensity activities. And specifically walking in nature, as opposed to urban settings and big cities. Studies on walking in nature show a reduction in cortisol levels, a decrease in anxiety and negative thoughts, and an improvement in concentration in children.