Cold and flu season has officially begun, and it's known that adults can contract these illnesses an average of two to four times a year. Many people notice that symptoms like colds, muscle aches, and sore throats become significantly worse after sunset. Now, experts have revealed exactly why this occurs.
They state that there are several reasons, but mostly, the answer lies in the body’s circadian rhythm, or internal body clock. Almost every bodily function is programmed to operate at full capacity at certain times of the day and to calm down at others. For instance, when the sun sets and the body senses bedtime approaching, the brain secretes fewer stress hormones like cortisol and signals the intestines to slow down digestion. However, some immune cells become more active, which are designed to hunt down and destroy pathogens like viruses.
This "fighting" leads to inflammation, an evolutionary tool that kills germs but is also responsible for cold symptoms. A decrease in stress hormones like cortisol can exacerbate the problem, as this chemical can effectively calm inflammation. Experts also highlight another important factor: “Simply put, cough and cold symptoms are worse when lying down. This is because mucus begins to accumulate at the back of the throat, a problem that doctors refer to as post-nasal drip.” Lastly, there is "a lack of distractions during the night that forces you to focus on the annoying cough that you can't get rid of."
