Who's the Most Vulnerable to Heat?

High temperatures can be harmful to anyone. However, some people a lot more vulnerable to heat than others. Learn more about these at-risk groups and some precautions they should take in this article.
Who's the Most Vulnerable to Heat?

Last update: 01 January, 2020

Certain people are more vulnerable to heat, whether it’s due to their specific body type or health conditions. These sectors of the population must be particularly mindful of their protection during the summer.

Of course, we all must follow basic heat protection measures. For example, we must wear the right clothes, stay well hydrated and stay away from the sun during its hottest hours. However, those who are more vulnerable to heat should maximize these measures.

The people who are most vulnerable to heat are:

  • Children under 5 years
  • People over 65
  • People with chronic diseases
  • Those who exercise or work outdoors

People who are the most vulnerable to heat

Children are quite vulnerable to heat

A child at the beach

Children, especially very young ones are particularly vulnerable to heat. This is because younger bodies lose fluids more quickly. Thus, they dehydrate faster. Likewise, children generate heat more quickly due to their size. So, you must protect them from direct sun when temperatures rise and look out for any overexertion during their physical activity.

Keep in mind that your little ones neither perceive the first signs of dehydration nor the effects of heat on their bodies. You’ll be able recognize them because they’ll be more irritable than usual.


Another group that’s highly susceptible to heat is the elderly. This is because the body’s thermo-regulatory center is in the hypothalamus, a region of the brain that regulates the body’s internal temperature. Unfortunately, this function gets slower as people grow older.

Also, members of this group can’t perceive their thirst as easily as they used to. So, they’re at greater risk of becoming dehydrated. So, remind them to drink fluids once in a while.

Additionally, older people sweat less than their younger counterparts. It’s for this reason that they tend to retain more body heat. Also, if their environment is humid, then it further inhibits sweating and there’s an increased risk of heatstroke.

People with hypertension

Excessive heat dilates the arteries and leads to dehydration. Both are quite negative for those afflicted by hypertension. So, consult your doctor regarding how to adjust your medications during hot weather.

What’s most common is for heat to lower tension. Therefore, the effect of your usual medications may lead to you reaching an inadequate level. It’s for this reason that you must have a doctor’s checkup so they can rule out any unpleasant surprises.

Cardiac and obese patients

An obese man affected by the heat.

High temperatures also affect cardiovascular health. Naturally, this effect is more serious in those who’ve had previous problems. This is because heart failure limits your body’s ability to cool down. As you can see, there’s a risk of heat overload. Plus, it’s also common for heart patients to use diuretic medicines so they constantly eliminate water from their body and this reduces their ability to sweat. It’s for this reason that they’re particularly vulnerable to dehydration.

Obese people also have problems cooling down. Usually, they sweat excessively when faced with high temperatures. Thus, they easily lose liquids and mineral salts and often become dehydrated. Likewise, as overweight people have a greater volume of body fat, this alters their temperature regulation. Therefore, they’re more likely to have a heat stroke.

Athletes and people who work outdoors

Finally, those who do physical activities outdoors are a lot more vulnerable to heat. Direct exposure to the sun increases the impact of high temperatures on them. So, both sun exposure and activity double their risk of dehydration.

All of these groups must be adequately protected and, where possible, limit their activities to those times of the day when the sun is not as strong. Also, they must hydrate constantly and drink twice the liquid they usually do.

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