If the average body temp. is 98.6 degrees, then why does it seem so hot when it's only around 75 or so?

Question

When I say 75 I'm not real sure about it. All I know is that where I live it seems hot when I know it's definetly not 98 degrees so forgive what I said before and please don't call me insane because people tend to have different point of views on different subjects. When you answer please acknowledge that I'm not quite sure about it being right at 75 degrees. Thank you!

P.S. I think it's also quite humid where I live.

Answer 1

The human body produces heat, but it's like a machine--it can't overheat, or it will lose function. Therefore, the body must constantly lose heat for it to stay at an equilibrium--this is why at temperatures less than 98.6, it still feels quite hot. Additionally, humidity and the sun is involved--your clothes trap in some heat, and humidity makes you sweat. While you are indoors, your sweat doesn't evaporate--so you're wet and hot.

Answer 2

When it is 75 degrees, the only consideration is the temperature of the air in the shade. Stand in the sun near the equator and you will be much hotter because the sun is a major source of heat. So are you thinking about times when you are in the shade or in the sun?

Now your body core also produces heat and this can be trapped with natural insulation and with clothing. Measure the temperature of your hand with the thermometer and if the temperature of the air matches, then your core will have a bit of difficulty expelling the extra heat generated from normal body processes. So how much heat is your body generating and how is it being radiated out? How much are you sweating and what is the humidity (counteracts the cooling effect of sweat)? Have you been physically active, and do you have a high metabolism or high degree of insulation around you? Active swimming can make 65 degree water in a swimming pool (where heat is radiated out most easily) seem normal (warm).

BTW, if you bring your skin temperature to 98.6, your core must be much higher than that because internal heat generation yields a natural heat gradient which forces the core to be hotter than the skin. A core temperature of over 101 (just 2 degrees hotter) is not good for normal body processes, and normal indicates the beginning of a fever. Just take the armpit temperature and add 1 degree for the core temperature, and if that temperature exceeds 102 degrees, you should immediately take steps to cool the body down following established medical procedures and to seek medical attention.

As a quick note, your own judgment of what seems hot or cold is highly partial to the condition of your body in the recent past, and should be checked against the judgments of others in normal, healthy people, or against a correctly-utilized thermometer. Feeling hot does not actually mean that you are hot, just hotter than your most recent history.

Answer 3

Hopefully I am not too technical using my knowledge of thermodynamics and heat transport, but here goes...

Your body operates at its best within a narrow range of internal temperatures, and it tries to regulate itself such that it maintains said temps. There is no internal cooling system in the body, only heat, so if the body is too hot, it has to rely on the outside air to keep cool.

At this point, you could do what's called an "energy balance" on your body and the air. The body is always generating heat (since the food you eat is metabolized into energy), and it is also losing heat to the surroundings. The rate at which it loses heat will depend on temperature, wind, humidity, and any insulation you have (i.e. clothing). There is a very well-known function for this:

0=Q - h*A*(delta T)

With Q being your body heat, A being your body's surface area, delta T being the difference in temperature between you and the air, and h (known as the "convective heat-transfer coefficient") being a constant that varies with the conditions of the air, and the clothes you are wearing. The only two of these you can really change is the temperature (i.e. heating and air), and the h constant (for example, using a fan results in a higher h value, which is why fans work, and why wind chill happens). Two things you can't change are metabolism (Q), and your body's surface area, though when you are overheated, you *can* remove clothing to expose more of your body's surface to the air, and you can stop moving and/or drink cold fluids to counteract body heat.

Typically, a clothed person is in equilibrium with still air (i.e. things feel just right) at around 72F, as you've likely noticed, though for some people, a higher or lower metabolism will adjust that temperature. If it get significantly higher, the temperature difference between you and the air isn't high enough to pull enough heat away, and because of that, you feel hot. If the temperature is too low, the heat loss you experience is more than your body can compensate for, and you feel cold.

Hope that answers your question.

Answer 4

Don't forget that everyone is different - 98.6 degrees is an average, some people run warm, some people run hot. The heat is a side effect from all your internal organs doing their job. Just like you get warm when you work hard, or too much friction causes warmth, your body produces heat when your guts are working. Plus the amount of body fat can determine weather or not you are warm in 75 degrees or cold. A person with more body fat is going to be way more warm that someone with none. Fat is an insulator.

Answer 5

It all depends on what you are used too......

In places where it gets to be 90 or so in the summer and you spend a lot of time outdoors or don't have air conditioning, 75 would seem really cool. But you are used to a higher temp.

If it was below freezing around 10 degrees for a week or so in the winter and the temp went up to 75 for a day you would sweat buckets.

Answer 6

It all has to do with heat transfer.

As the body works, it generates heat which must be discharged to the atmosphere. The rate at which heat is discharged is directly related to the difference between the two temperatures. In other words, the colder it is outside the faster the body can discharge the heat it generates.

In order for the body to cool itself when then outside temperature approaches or exceeds the body temperature it must rely on the heat being lost due to evaporation. Therefore, we sweat, the sweat evaporates and this act takes some of the bodies heat with it.

This is why humidity also affects the transfer of heat (makes it feel hotter). If the air is already moist (humid) it is much more difficult for the evaporative effects of your sweat to work.

Answer 7

It is because the skin is designed as a buffer to keep the body's temperature at 98.6 degrees. It is also because the skin is designed and adapted at certain degrees.

For example, if you are used to living in the USA and you decided to move to the tropics then therefore you would feel hot/warm once you migrate to the tropics. This happens because once the temperature rises, the body temperature also rises. Once this happens, the skin will start to produce sweat and try to cool the body.

The reverse happens when you have a fever. Your body temperature is higher than 98.6 but the temperature in the environment is still the same. This make you chill and feel cold because, in effect the temperature in the environment is "colder" than usual.

Answer 8

It has to do with how the body rejects heat.

There is a range (which is different for all people) of comfort. The middle of that range is roughly 75 degrees, 50% relative humidity.

The body rejects heat through the skin. As the ambient (meaning the temperature around you) temperature rises, and gets closer to body temperature, the rate of heat rejection decreases due to the smaller difference in temperature. Heat transfer is directly related to the temperature difference (called "delta T"). Now when your body starts to feel warm, it starts to sweat which is an additional method of cooling called evaporative cooling. Your body cools off more due to the energy needed to evaporate the sweat off your skin. It is generally when people start to perspire that they say that it "feels hot". If the person is doing something physically exerting, the body will need to reject even more heat, and increase the rate of perspiration. Note that when it is too humid out, it even becomes difficult for the air to absorb the moisture off your body. And in extreme heat and humidity conditions, there is a risk for heat stroke (hyperthermia), when your body is unable to reject enough heat.

The reverse is also true. At a temperature less than about 65 degrees, the environment absorbs more energy from our body than is generally comfortable. People adjust by adding more insulation in the form of clothing. In cases of extreme cold, the environment is taking too much heat from the person, and that person is at risk for hypothermia.

Answer 9

Humidity has a lot to do with it! Evaporation is a cooling process and our body uses evaporation (and exhalation to some degree) to cool body temp. Higher humidity slows the evaporation process. This is why you can also feel "cold" at 75 if the humidity is very low. Along with the humidity you also deal with body metabolism which can make you "feel" warmer as when you eat those hot peppers!

Answer 10

Some people have already answered this correctly but I'm going to try to simplify. If your body is at 98.6 whether its 50 degrees or 70, or 100 outside, it doesn't matter, your body is still at 98.6 right? Then all that matters is what works best for your body on the outside, which is 72 degrees. Thats the temp. that keeps our inner body at 98.6 degrees most easily. Our bodies need to work the least at that outer temperature to keep the inner temp. at 98.6. get it?

Answer 11

My guess would be that the 98.6 degrees in your internal temp. because your skin usually heats or chills to the outside temp and that is why 75 degrees feels hot to the skin but you will probably notice that after a bit (unless in direct sunlight with no wind) that the heat will not be as noticable as your bodies interal thermometer kicks in to cool your body down.

However, that is just my guess I am not a doctor.