A study published in the journal eLife, has investigated how what we eat can affect post-meal sleepiness and nap length.
Researchers from the Scripps Research Institute in the USA tested the consumption of salt, sugar and protein in fruit flies — insects used for their genetic similarities with humans — and found that meals with higher levels of protein and salt could promote sleep and lead to longer naps.
“While we expected that flies defective in protein sensing would experience post-meal sleep in a similar way to those fed only sucrose, we found instead that they had a waking response.”
“Our analysis suggests that ingested protein promotes both sleep and wakefulness, and that the wakefulness is counterbalanced by Lkr neuronal activity. “
The research provides a starting point for future work investigating the genes and circuits that link meal size, protein and salt to post-meal sleep.