Why do we crave sugar and fat when stressed?

This question, although very common, is layered in intricate physiological and biochemical systems, cause and effect. But, let's try to cut through the fat (so to speak) and provide you an easier to read summary of why we tend to gravitate to these deliciously sugary foods when we face moments of heightened stress.

A Brief Dalliance with History

From the dawn of time, our brains developed a software to ensure that our hunter/gatherer ancestors could survive by installing a program that instinctively attracted them to higher value foods (generally higher in calories and fats/sugars). These foods were generally known to be of higher value as it provided greater sustenance and energy in a society where food was not abundant and energy needed to be prioritised.  In other words, during hunting season, our ancestors wouldn't spend their time picking the leaves and grass to make salad as the 'energy reward to time' ratio was not balanced. They knew that spending time hunting wild game (ie. animals), would benefit a larger population of the tribe as well as provide sustenance and caloric value.

Onward to the UberEats Generation

Fast forward to industry 2020, and food has never been more convenient (and tasty) in modern cities. Regardless of how technology and food availability has changed, we still carry that embedded program that draws our attention to the higher value foods especially in a state of hunger. After all, it's a survival mechanism.

Higher value foods also tend to be more palatable nowadays thanks to food additives and flavour enhancers (or just higher fat and sugar ratios in general) and as a result, provide us with a greater biochemical reward. This reinforces to the brain that this food not only provides energy but makes us feel comfort and happiness all in one bite (or 5). This is learned behaviour by association. 

Connecting the Links

So, in moments of heightened or prolonged stress, the brain takes this learned behaviour, recognising that these high fat/sugar foods could make us feel better and throws us the sugary, fluffy or deep fried bone. We grab it, chomp at it and immediately feel the love..even if only for a minute. 

The high palatability of the food has been found to ‘dampen the activity of the stress response system [to make] us feel better’ (Guyenet, 2017). Based on this conclusion it’s safe to say that some of us have found a way to self-medicate during both chronic an acute periods of stress, however, this often leads to excessive weight gain over time. 

Mary Dallman, neuroendocrinologist from University of San Fransico suggested that based on the results, the food itself may not be the self-medicating key, but rather, the activity that produces the high reward feeling. Based on this, to overcome habits of overeating during times of stress, possibly swapping it for a different activity that produces similar results can work. This becomes very subjective and a lesson in trial and error.

What activities bring you relief or joy that could also dampen the stress response system?

Here's a list of activities that some find useful:

- Yoga

- Meditation

- Exercise

- Painting/Drawing

- Sex

- Reading, etc.

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If this topic triggered a light bulb moment and you want to learn more, check out the references below and some additional reading that can help you understand the intricacies of the brain and the research (that really only skims the surface) forming links between overweight and obesity and the brain. 

REFERENCES

Guyenet, S. (2017). The Hungry Brain (1st ed.). New York: Flatiron Books.

Tomiyama, A., Dallman, M., & Epel, E. (2011). Comfort food is comforting to those most stressed: Evidence of the chronic stress response network in high stress women. Psychoneuroendocrinology, 36(10), 1513-1519. doi: 10.1016/j.psyneuen.2011.04.005