15 Common Causes of Heat Intolerance You Shouldn’t Ignore

Heat intolerance is a condition in which the body has difficulty regulating its temperature. Heat intolerance can occur when a person is exposed to hot or humid weather, exercises, or engages in other strenuous physical activities.

The main symptoms associated with heat intolerance are dizziness, nausea, headaches, and weakness. If any of these symptoms persist for more than 24 hours after exposure to heat, it’s essential to see a doctor for an evaluation.

People more likely to experience heat intolerance include those with heart and lung problems, overweight or obese, and the elderly. Before anything else, people should be aware of more common causes of heat intolerance. The following are some of its most common causes.


The most common cause of heat intolerance is dehydration. This occurs when the body loses more fluids than it can replace through drinking and sweating. This causes the blood to become thicker and less able to circulate quickly enough through the vessels. As a result, the heart works harder to pump blood through the body, leaving fatigue.

Dehydration can be caused by overexertion in hot weather or any other activity that leads a person to sweat heavily (including sex). To prevent dehydration, make sure to drink plenty of water before, during, and after strenuous activity, at least 12 ounces every hour if possible, and replenish any salts that may have been lost. If you begin to feel dizzy or weak due to lack of hydration, you should take time out from whatever activity you are doing immediately to prevent heat exhaustion.