“Your body, especially when exposed to the sun, has to work hard to maintain a consistent and normal internal temperature,” Casey explained to Live Science. When we are hot (which in Israel is actually most of the year), the body makes several changes to regulate the temperature. Like the expansion of the blood vessels – a process called vasodilation, which allows more blood to flow near the outer layer of the skin. In this way the blood actually manages to cool down and release the heat outside. In addition, the secretion of sweat is also a process that the body does to cool itself.
For our body to be able to perform these tasks, the heart rate increases and so does the metabolic rate. “All the extra work the body is doing eventually makes you feel tired or sleepy. Also, many of us don’t drink enough and one of the symptoms of dehydration is fatigue,” added Dr. Casey.
So what should we do to catch a cold?
A common mistake people make when they are cold is to go to the fridge and drink a cold beer. The problem is that alcohol causes an increased secretion of urine and thus may cause dehydration. The best way to fight dehydration is of course by drinking water and snacking on a salty snack – like a pretzel or chips made from baked potatoes, Casey says.
It is important to be aware of the symptoms of heat exhaustion: profuse sweating, rapid pulse and feeling weak or tired. “If this happens, I recommend finding a cool place, drinking water and seeing a doctor, if the symptoms do not improve after about an hour,” says Dr. Casey. It is advisable to be in a shady and cool place during the hottest hours of the day – between 10 am and 2 pm.