Experts: Afternoon fatigue linked to more than just food

Health experts have analyzed the causes of "afternoon sluggishness" that often occurs after lunch, describing it as a common phenomenon driven by several biological factors, not just food.

They explained that the longer a person stays awake, the more adenosine accumulates in the brain—a compound associated with increased drowsiness. As the body enters the early afternoon, it naturally becomes more inclined to sleep. As sleep pressure continues to rise, feelings of fatigue become more pronounced, according to Russia Today, citing Medical Xpress.

According to the experts, eating can intensify this sensation, but it is not the sole cause. When we have lunch, the signals exchanged between the digestive system, the brain, and metabolic processes change. The brain receives information about stomach fullness, nutrients, and gut-related hormones. Large lunches are linked to greater drowsiness and reduced alertness afterward, but there is no strong evidence that any specific nutrient—such as fats, carbohydrates, or sugars—is solely responsible for this state.

They added that caffeine does not provide the brain with extra energy; instead, it primarily blocks adenosine receptors, temporarily reducing drowsiness. As adenosine continues to build up, caffeine cannot replace sleep. Consuming caffeine late in the day may also disrupt nighttime sleep, potentially leading to increased fatigue the next day.

The experts concluded that afternoon sluggishness should not be seen as a sign of laziness or poor concentration. Mental performance and alertness fluctuate throughout the day, influenced by the body's natural rhythm, time awake, and the nature of tasks. The solution may lie in understanding and adapting to this rhythm, rather than constantly trying to resist it.