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Ughh...Is it hot in here
or is it just me?
00:00:08,800 --> 00:00:10,620 Hey everyone! Thanks for watching DNews
I'm Julia. And I'm Trace
Humans are warm blooded, so you would think that
we would be warm all the time,
but that's actually not what warm blooded means.
There are those of us who are, well, cold all
the time. But that doesn't mean we're cold blooded.
Cold blooded animal's body temperatures
are subject to the temperature of the room they're
in, whether that's the forest,
sitting in the sun, or hanging out in the cozy
kitchen. On the other hand, warm blooded
animals have the ability to internally
regulate their body temperatures, independent
of their environment. It's called being
homeothermic, and it's common in
mammals. Humans average around 98.6 degrees Fahrenheit,
cats and dogs have around 101
or 102. Dolphins are around 95.
Lions are over 102,
but note that I said "average".
Body temperatures can range, and in humans
women are usually colder than men
and older people are colder than younger.
Temperature regulation starts in the
brain and is controlled by hormones.
The brain takes into account the body's core
temperature and the temperature of the
outer skin. Fatter people tend
to feel warmer because their core
organs are all toasty. Though
their extremities are colder. While
people with lower BMI's tend to feel
colder because blood pumped through the extremities
needs to be really warmed up
when it gets back. Warming the blood is the
major way we can regulate our internal
temperatures. When thermoregulator cells
in our skin detect a cold environment
they constrict our capillaries and blood vessels
in a process called vasoconstriction.
This can cause the flow to slow as little
as 0.02 liters per minute
in the far-flung parts of the body,
the highest can be 2-3 meters per
minute. The lack of warm blood is what
makes my hand and feet cold,
and yours too.
Yes, which of course has to do with the amount
of body fat, but also has to do that
women's bodies work harder to keep their core
body temperatures up, in comparison
to men. This leaves fewer energy
resources to warm the extremities.
Human biology dictates that men tend to
have more muscle mass and women tend to have
more fat. The working of muscle
generates heat, while fat cells store it.
Researchers at the University of Utah
measured the temperatures of men and women's
hands and found men's hands
were 90 degrees on average, while
women's were 87.2
And a study in The Lancet found the
hormone estrogen is part of this
temperature regulation system too,
which is a whole other bag of
cats. During the menstrual cycle,
a woman's body can change as much as 1.8 degrees Fahrenheit,
which is a huge difference when you're talking about the
core temperature of a human.
Age, diet, exercise and sleep will
also effect body temperatures
and the amount of warm blood getting to our extremities.
People who are more active tend to have
warmer hands and feet overall than those
who don't. People who smoke have more vasoconstriction
cooling the extremities. When you fall asleep
women's body temperatures lower more
rapidly than men's. Of course
some of this is person to person
dependent. My feet are frozen
at night, but during the day
I'm always hot. And it's
not even just about being physically hot,
it's also our perception of temperature
which affects our feelings of
whether we're hot. Right! If you're surrounded
by people you are comfortable with you'll feel
warmer. Also, a Canadian study
found people who are lonely or feel
isolated are more aware of a
cold body temperature, while socially
connected people tend to feel
warmer. That's true. What about you guys,
are you always hot? Are you always cold?
Let us know down in the comments. Make sure you subscribe
as well to DNews, so you can get more of this
everyday! Also, check out this video
over here about whether shivering
could help you lose weight.
Thanks for watching DNews, see you later, guys!
See you next time!