Do you often find yourself fighting the urge to nap after you’ve eaten a huge meal? Or feel as though you could literally fall asleep right there on the couch not long after you’ve inhaled a delicious dinner and dessert? That’s the infamous food coma for you, creeping up on you when you least expect it.
When was the last time you ate yourself into a food coma? I know I did just the other day at my favourite Indian restaurant. I just can’t seem to help myself when it tastes so damn good! It’s the feeling many of us know all too well, especially when the festive season comes around. In America, the annual food coma is considered to hit hard around Thanksgiving. However, here in Australia, I definitely think we like to take every opportunity to indulge in our favourite pastime of eating (I know I do). From Christmas to New Years, as well as Easter and what seems like every family member’s birthday, us Aussies never seem to learn our lesson when it comes to eating our way into a food coma.
The medically recognised condition and much more technical term for the well known food coma is classified as postprandial somnolence (try saying that ten times over and over again). While we’ve all experienced this condition at some point in our life, the question you’re probably asking is how the consumption of food leads to us feeling so sleepy? I’m afraid the response to that is no simple task. In fact, the process of postprandial somnolence is actually quite complex (as if the name doesn’t give that away already) and isn’t as straightforward as you would assume.
Firstly, lets take a look at postprandial somnolence from a more general perspective. Following a big meal, the activity of the parasympathetic nervous system within the body increases. This system is primarily responsible for digestion. Therefore in order to rest and ultimately digest, the activity of the sympathetic nervous system in turn decreases. This system is characteristically responsible for one’s fight or flight response. As a result of this, the body’s blood supply is directed towards the stomach to aid in the digestion process and facilitate the transport of your recently digested meal. This then results in a decreased blood supply for the rest of your body, which is believed to be a contributing factor as to why you feel quite lethargic and sleepy after a big meal.
Delving into postprandial somnolence a little deeper is where a number of crucial pathways come into play. As blood glucose levels rise following a meal, a hormone called insulin is released to balance out these levels. Likewise, insulin is known to aid in the absorption and use of glucose from the bloodstream. Therefore, the more insulin that is released is directly related to the successful transport of a key amino acid. This amino acid, called tryptophan, travels through the bloodstream and across the blood brain barrier. Tryptophan is then further metabolized to the chemicals serotonin and melatonin, both of which are responsible for drowsiness. This process is ultimately the leading contributing factor to the generation of a food coma.
Check out this interactive explanation of postprandial somnolence to see how your usual food coma occurs, from a more comprehensive and visual perspective:
In truth, the process is a whole lot more complex than that, involving countless pathways, hormones and other components on a biochemical level. Unfortunately, to explain the multiple mechanisms and variables of the common food coma would require a great amount of detail and nutritional jargon that is quite difficult to understand. While research has been conducted in this field, there is still a long way to go, as the dynamic relationship between food and sleep is not completely understood.
Studies do suggest, however, that the higher the fat and the higher the carbohydrate content of the meal, the sleepier you will become. Similarly, the higher the glycaemic index of the food you eat can also lead to the likelihood of developing postprandial somnolence. As seen to the right, this is due to elevated blood glucose levels and the subsequent increased release of insulin in the bloodstream, as previously discussed. Foods of a high glycaemic index include white bread, processed cereals and potatoes, so watch out for those ones!
It seems as though once you’re in a food coma, there is unfortunately no way out. If you’re hoping to avoid your usual food coma or perhaps feel a little less sleepy after your next food-related celebration, it is important to keep in mind the size as well as the type of food that you’re eating. Now that you’re more aware of how a food coma occurs within your body, hopefully you’ll be prepared for the next one. With that being said, to overcome the ever so frequent food coma all I can say is good luck, eat wisely and may postprandial somnolence be ever in your favour.
Also published on Medium.