• You may look in the mirror and think you know what you see but there’s actually a
whole lot about your body that is hidden from you.
Do you have powers you never realised?
And what weird stuff is going on inside?
Here’s fifteen facts about your body that will blow your mind
15 – Fingernails grow faster on good hand • Your fingernails grow at about 3 millimetres
a month but this is an average, because there’s actually quite a lot of variety.
For example, if you are right handed then the nails on your right hand will grow slightly
faster than those on your left.
This is thanks to the increased blood flow in your so-called “good hand”; you use
it for more activities like writing and eating.
14 – Hear boiling water • Your hearing is actually far more accurate
than you think and you have some abilities that you probably weren’t aware of.
Definitely the coolest is that you can hear the difference between hot and cold water.
Try it out; fill two similar cups, one with boiling water and one with cold water.
Now, get your mate to pour them into another cup, while you cover your eyes, and you have
to work out which was first, the hot or the cold.
• It’s a sound you’ve heard so many times that your brain recognises the difference,
even if you never noticed.
13 – Eye colour paternity • There are around 6 genes which control
eye colour and most humans have one of around 8 shades.
But did you know that eye colour can be used to check paternity.
• The most definite example is that a brown-eyed child must have at least one brown-eyed parent.
If both parents are blue-eyed, there’s also only a 1 in a hundred chance of having a green-eyed
child.
So, that’s probably going to be an awkward conversation for one of our viewers.
12 – Finger length and testosterone • Take a look at your hands.
If your ring finger is longer than your index finger then you were exposed to a higher rate
of testosterone while you were in the womb.
This is true for men and women, just the levels will obviously be different.
• There are a huge amount of studies about what else this indicates.
For example, in men, a longer index than ring means you have a much lower risk of prostate
cancer and a higher probability of being gay.
11 – Calorie restriction lifespan • We don’t know the exact cause of again
but it’s thought that one major factor is DNA becoming damaged.
• The best way to limit damage is to avoid having any unnecessary energy in the cells,
so, you only give them the precise amount they need.
• And what does this mean for you?
Well, you have to eat a calorie restricted diet for your entire life.
That doesn’t mean starving yourself but you should only have the exact amount you
need, to avoid unnecessary wear and tear on a genetic level.
Sounds fun, right?
10 – Female sperm heavier than male sperm • Now, for good reason, you probably don’t
think about your dad’s balls that often.
But, did you know that there are two types of sperm in there; male and female?
The female egg carries the X chromosome so if it mixes with an X sperm, you get a girl,
and if it mixes with a Y, you get a boy.
• The X chromosome carries about 2000 genes, while the Y has only 78.
This means that X sperm is actually about 3% heavier than the Y so the pull of gravity,
after sex, could have a very small influence on whether you’re born a boy or a girl.
Sorry for making you think about your parent’s sex positions.
9 – Tiredness is two chemicals • Sleepiness is controlled by two different
chemicals that your body releases; adenosine and melatonin.
Adenosine is known as sleep pressure; you build it up while you’re awake and then
break it down while you sleep.
Caffeine attaches to adenosine receptors and speeds you up, where adenosine would slow
you down.
• Melatonin is related to light.
You release it when it’s dark to help make you drowsy.
This is why it’s bad to stare at your phone in bed; it tricks your body into still thinking
it’s day time.
8 – babies don’t have tears • If you asked 100 people “what do new-born
babies do”, about 99 percent would say “sleep, poop and cry”.
But the funny thing is, despite being famous for crying, babies don’t have tears.
• It’s only after 1 to 3 months that they begin to develop tear ducts
7 – a quarter of your bones are in your feet
• When you’re born you have about 300 bones but some of these fuse over time and
you end up with 206 as an adult.
And a quarter of those are actually in your foot.
• Feet are much more complicated than you think, since they’ve had to adapt to carrying
around a large amount of weight.
Each foot has 26 bones, 33 joints and over 100 muscles, ligaments and tendons
6 – one hair can support 100g • Your hair is actually extremely strong
and just one strand can hold 100g.
When you combine all 150,000 on your head, they could take the combined weight of 12
tonnes, which is about as much as two fully grown elephants.
• Pound for pound, this puts human hair on a level with aluminium.
It’s also about the same as Kevlar so you could stop a bullet with it if you had enough
to fill a vest. 5 – left and right lung are different
• We think of our lungs as a pair, just like our kidneys or our eyes, but there are
actually quite a few differences between your left and right lung.
• The right lung splits into three lobes, which are like the main branches of a tree.
But the left only has two and also has a dent in it so that it fits around your heart.
4 – Your arms width is your height • Here’s a cool think you can show people.
Get a volunteer to lay on the floor so their head just touches the wall, then you should
stand so your toes touch the bottom of their feet.
Now, make them get up, turn 90 degrees and spread their arms out; they’ll realise that
the width of their arms at full spread is exactly the same as their height.
• It’s just like it’s shown in that famous Da Vinci sketch
3 – Heart can beat to music • You know that if you dance a lot your
heartrate will increase, thanks to all the exercise.
But, you don’t actually need to move at all for the music to have an impact on your
heartrate.
• So, part of the reason that calm music relaxes you is that your heart slows down
and matches the lower tempo.
The opposite is true for up-tempo genres like hip hop or techno.
2 – lips are 100 times more sensitive than finger tips
• If people were asked what the most sensitive part of the body was, a lot would go for fingertips,
maybe nipples or some other sexy part.
But it’s actually your lips that have the highest density of touch receptors.
• You need these especially for speech, as well as dealing with all the various foods
we cram in our mouths.
1 - hyoid bone gave us speech • The main reason human beings have been
able to work so successfully together, from hunting mammoths to building flat-pack furniture,
is thanks to our ability to speak.
• And the bit of evolution that gave us speech wasn’t the lips or tongue; it was
a bit of the neck called the Hyoid bone.
• This horseshoe shaped part is the only bone in the body that’s not attached to
another bone.
It’s supported by neck muscles and without it we’d only be able to hoot and howl like
monkeys, rather than create the complex sounds of our various languages.