It’s even worse during these two hours of the day, researchers show.
You too have systematically a break after lunch ? This is what doctors call “postprandial fatigue”, a sudden state of fatigue that occurs around 30 minutes to 2 hours after the meal. We yawn, we snort, we are less concentrated and less vigilant… This fatigue is even stronger after a generous meal or high in carbohydrates and fats. And it’s even worse if you drink alcohol…
The worst hours of the day
In a meta-analysis published in the magazine Yale Journal of Biology and Medicineresearchers have shown the evolution levels of attention and alertness during the day. The studies compiled in this meta-analysis were based on recording physiological and cognitive performances (measurement of reaction time, working memory, etc.) at regular intervals (every hour) in individuals living in their normal environment (they followed their usual daily routine). According to researchers, for a person who usually sleeps from 11 p.m. to 7 a.m. and with an intermediate chronotype (neither early riser nor night owl):
- Attention is at a fairly low level between 7 a.m. and 10 a.m.
- Attention improves between 10 a.m. and 2 p.m., with a peak in alertness around noon
- attention decreases after lunchbetween 2 p.m. and 4 p.m. (the famous postprandial fatigue or “post-lunch dip” in English)
- Attention then improves in the afternoon and early evening, between 4 p.m. and 10 p.m.
- Attention decreases again at night, from 10 p.m. to 4 a.m.
- Attention reaches its lowest level at dawn and early in the morning, between 4 a.m. and 7 a.m.
Attention corresponds to our ability to interact effectively with our environment. It is crucial for the execution of all human activities, whether to learn, to work, to play sports, arts, social interactions or recreational activities. “According to the data examined, healthy individuals present good levels of cognitive performance (attention, vigilance, working memory) from 10 a.m. to 2 p.m. and from 4 p.m. to 10 p.m.“, summarize the researchers, suggesting carrying out the tasks of the day that require the most attention during these two time slots.
Carbohydrates make you tired even more
Several biological reasons explain this fatigue. Already, for digestion to take place, the pancreas must release insulin and this surge of insulin causes an increase in serotonin, a neurotransmitter that prompts you to fall asleep. Afterwards, “we feel sleepy because blood is diverted from the brain to the intestine to process all this foodindicates to theHuffington PostDr. Rich Joseph, attending physician at Brigham and Women’s Hospital in Boston. The larger the meal, the more your blood goes to the intestine to aid digestion. Less blood to the brain, so you feel more sleepy“. Foods with a high glycemic index like pasta, white bread or fruit juices tend to cause more spikes in blood sugar, which can make us irritable, tired, and less attentive. To avoid this slump after a meal, it is advisable to eat your food in good order (first vegetables, then proteins and finish with starchy foods), avoid foods rich in sugar or alcohol and move around after the meal to boost adrenaline and activate the muscles.