Articles, Blog

Blood Sugar Levels

August 24, 2019

Let’s think a
little bit about how we can tell whether our body
is processing glucose properly, and whether maybe
we have diabetes. And I want you all
to take all of this with a huge grain of salt,
because I am not a doctor. This is not medical advice. My goal here is to kind of just
explore the subject with you, and to try for all
of us to get a better understanding of things. So let’s think about what might
happen after we have a meal. So let me draw a
little chart over here. So let’s call this hours. And then on the
vertical axis, I’m going to talk about our
concentration of sugar in the blood. So blood sugar concentration. You could call it
glucose concentration. Blood sugar concentration. When we’re talking
about blood sugar, we’re talking about glucose. And let me draw a couple
of points on this chart. So maybe this is 50. And our units are going to
be milligrams per deciliter. Actually, let me
just do it this way. Let me just say that everything
is in milligrams per deciliter. And we’ll talk in
future videos about how we can relate these
units to everyday terms. But let’s say that
this right here is 50. This right here is 100. This right here is 150. And let’s mark it
right here at 200. So let’s think about what would
happen for a normal person. Let me mark some
hours over here. So hour 1, 2, 3, 4, 5, 6, 7, 8. That’s probably good enough. So in a normal person, when
they haven’t eaten anything for a long time, let’s
say greater than 8 hours– so their fasting
blood sugar will be right around 80
milligrams per deciliter, give or take a little bit. There’s a range around
that, but I just want to show you what would
happen to a normal person. So at 80 milligrams
per deciliter, their blood sugar
will kind of be– should, hopefully, be
right around there. And sometimes this
fasting blood sugar– and maybe we’re assuming
that this is in the morning. So maybe this hour one
is 7:00 in the morning. So they haven’t
eaten for a while, and that’s why it’s
fasting blood sugar. This is also– you’ll
sometimes hear doctors, I’ve heard my wife say
this word without knowing what it meant– they’ll
sometimes say preprandial, which is a very fancy word
which just means before a meal, prandial is literally
before eating. After the meal, you’re
talking postprandial. So it’s a very fancy word for
a very simple idea, eating. So let’s say at hour two, this
individual eats breakfast. So this is where the individual
is going to eat breakfast. Now in a normal person, when
that person eats breakfast, there’ll be some carbohydrates
in that breakfast, and it will be broken
down into glucose, and that glucose will
enter the bloodstream. And so their blood
glucose will go up. It’ll slowly go up. And I was reading some studies. They say it kind of spikes at
about 45 minutes into a meal. So let’s see. 45 minutes is over there. So maybe it’ll go
up to about there. And in a normal individual,
the blood glucose really shouldn’t go up above 120
milligrams per deciliter. And there’s obviously
exceptions to all of these. We’re just kind of saying,
a normal breakfast, a normal person. They’re not eating
a pint of honey. They’re not doing
something crazy. So let’s say 120 would
be right around there. A normal person, someone
who does not have diabetes, it would be unlikely that
it would go above that. And then actually,
after about two hours, they’re getting pretty
close to normal. They get back under 100
milligrams per deciliter. And then you go
beyond two hours, they just kind of get close,
back to their baseline, to that 80 milligrams
per deciliter. So once again, this is normal. And of course, don’t
freak out if you were to take a blood
test one morning, and you were at like 85
milligrams per deciliter. You’re still not
far off from normal. So obviously, there’s
some variation from person to person. Now, if someone has diabetes,
if either they have type 1, they don’t have enough
insulin to actually process the glucose, or if they
have enough insulin, but their body is
desensitized to it. The insulin isn’t being
processed properly so they can’t
process the glucose, we’ve seen that the glucose
concentrations will go up. And so, in general, if you
were to wake up one morning after not having eaten
for more than eight hours, and you were to prick
your finger with one of those little glucose monitors
you can get at the drug store, and in your finger,
the blood sugar levels, if you were to find
them to be– Let’s say you were to find them to be
at 140, that’s 140 milligrams per deciliter. It’s a good indication. I mean, you shouldn’t freak out. You should do multiple
tests and make sure that it wasn’t a false
reading or any of that. And you should
definitely see a doctor. Once again, don’t view this
as any type of medical advice. That is not the purpose of this. The purpose of this
is just to understand a little bit of what’s going on. Don’t change your lifestyle
based on anything I tell you. All right. But if you do experience
that, it looks like, at least just from
that one data point, that your body isn’t
processing sugar properly. Because you’ve had over eight
hours to process the sugar, for insulin to go into
your bloodstream and allow glucose to be taken up and get
back down to a normal level. But it still hasn’t gone there. So if you were to test
a value like that, you should be concerned. In general, the threshold, and
I’ve seen multiple thresholds here, are between 100
and– I’ve seen high, kind of mid-120s to 130
milligrams per deciliter. So that’s kind of– let
me do it in this range. If your fasting blood
sugar is above this line right here– remember,
the fasting blood sugar. Not after you’ve eaten a meal. Your preprandial,
before a meal– if it is above that
threshold right over there, then you should at least– you
should definitely see a doctor and make sure that they can
see if you have diabetes. But this would be
cause for concern. Another thing is
if after a meal, it spikes well
beyond that, we’re talking if it gets beyond 180. And once again, these
are all just thresholds that doctors have come up with
and researchers have come up with that say, hey, this
is a good indication that somehow you are not
processing glucose properly. So 180 is up here. And I’m drawing it
as a squiggly line because it’s kind of a range. It’s not like if your blood
glucose is 124, you’re safe. And all of a sudden at
125, you have diabetes. No. They’re not that
different than each other. But they have to set
up some threshold just to kind of have a
threshold, I guess. So if your blood sugar,
after eating a meal, were to spike up
to, let’s say 200, once again, that would
be cause for concern. So in general, if
someone has diabetes, because they’re not processing
the glucose properly, their blood glucose might
look something like this. So maybe their
fasting blood glucose is right around 125, 130. It can move around. Then they have a meal. Then it might spike up. Obviously, they can process
some of the glucose. Otherwise, they would die. But it’s not being
processed properly. So the glucose levels don’t
go down to where they should. And maybe some glucose gets
taken up from the blood. Obviously they’re
living, so their cells are metabolizing something. But it never gets down to
the normal 80 milligrams per deciliter. It might settle down, back
to something in the 120 range or something like that, which
would be cause for concern. And in general, if
you’re someplace– I’ve seen the threshold if
you’re above 100 on a fasting basis, that’s cause for concern. You should maybe
adjust your lifestyle. And if you’re above 120,
130 after meal, once again, you should also be
slightly worried that you might maybe
are prediabetic or you have some risk
of developing diabetes. So if someone has
blood sugar like this, they’re probably diabetic. And if someone has
blood sugar like this, they should be worried. But once again, I
am not a doctor. Don’t take any of
this as advice. This is really just our
attempt to understand things a little bit better.

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  • Reply Petter Schjoldager April 4, 2011 at 4:43 pm

    You should start a religion… like khanianity! You'd rule the world

  • Reply Raphael Rollo April 4, 2011 at 4:48 pm

    Cool Man U always Rock!! 🙂

  • Reply Andrei V April 4, 2011 at 4:56 pm

    you're doing biology again! yey!!

  • Reply Izhueful April 4, 2011 at 6:43 pm

    @scottyurfunnylol Oh god, you just made a fool of yourself, try watch the previous movie, and then think again.

  • Reply jjkul1 April 4, 2011 at 7:09 pm

    I would be better to draw your graphs and diagrams (perhaps just the axes) BEFORE you start your presentation and keep them around and switch between them on need. This will shorten 3 minutes of an average lesson.
    Otherwise, we love you Khan.

  • Reply Charlymaumushi April 4, 2011 at 9:17 pm

    Nice. your awsome.

  • Reply Jim Howard April 4, 2011 at 11:33 pm

    Can you explain the relationship of the current blood sugar level with the ratio expressed in A1C tests?

  • Reply klipngirl April 5, 2011 at 4:59 am

    Loved the comment about eating a quart of honey for breakfast, it made me laugh. There may be some bears who actually do… 😛

  • Reply Bustah April 5, 2011 at 5:47 am

    Very helpful, thanks.

  • Reply Hot Pepper Lala April 5, 2011 at 5:48 am

    We need a Salman Khan Hospital

  • Reply Barry Williams April 5, 2011 at 7:24 am

    Excellent video. Thank you.

  • Reply boeing747200lr April 5, 2011 at 3:41 pm

    I think Sal explained it 100 times better than a doctor would have!

  • Reply cutifruit1004 April 5, 2011 at 4:59 pm

    some people don't have money for tutoring..thanks to khan he gives people an opportunity to learn.

  • Reply warrenlaurde April 8, 2011 at 1:06 am

    Normally I don't comment because many of your viewers object to your videos on philosophical grounds when you're trying to educate, not evangelize. But this is life-and-death, and they cannot rely on the most crooked health care system in the world (in a country that uses medieval units of measure) to protect them. BGL meters are available over-the-counter and Americans must be proactive in their own care. Their nation is geared towards consumption and medication, not prevention.

  • Reply Iceabella December 7, 2011 at 4:39 pm

    Can't you write the translation from mg/dl to mmol/l? You don't use mg/dl in Europe when it comes to bloodsugar. 🙁

  • Reply lizmariposa1 December 20, 2011 at 10:44 pm

    @Iceabella mg/dL divided by 18 = mmol/L.

  • Reply falubii February 28, 2012 at 5:09 am

    @warrenlaurde K, but they still need to be available for Type 1 diabetics.

  • Reply CarlosSpicyweiner52 April 12, 2012 at 1:55 am

    Nice video

  • Reply normalbloodsugar October 25, 2012 at 7:17 am

    Glad you explained the preprandial/postprandial. Those are definitely $10 words. 🙂 The explanation of a fasting blood sugar was very clear.

  • Reply Indira Murray December 2, 2012 at 8:21 am

    Khan and Sal is the best on youtube thus far….keep up the good work I received a 93 and 95 percent on my pathophysiology tests! You are gifted! God Bless you for being so kind to help us.

  • Reply Rome_World January 10, 2013 at 8:13 pm

    They're the same people

  • Reply S190K June 3, 2013 at 2:48 am

    Dam Khan Academy is TAKIN' ALL OUR JERBS!

  • Reply Timothy Johnson October 3, 2013 at 2:06 am

    I am a diabetic. It sounds as though you MIGHT be in danger of being one as well. What MIGHT be happening is your blood sugar level is getting gradually higher, but not so fast that your body can't process it. Your body builds an ever-rising tolerance for the sugar in its bloodstream.
    To not eat for a while MIGHT bring your level down to a more normal (as in, avg, human) state but for you, it is too low.
    You may want to consult your doctor and see what your blood sugar levels are to be sure.

  • Reply Timothy Johnson October 3, 2013 at 2:21 am

    This is what happened to me. When I was diagnosed, my blood sugar level was above 1100. That's right, above one thousand, one hundred. My demeanor was normal. I acted normal and–to the astonishment of the people in the ER and ICU–was conscious, not comatose.
    I was unquenchably thirsty. 1 gallon of milk, a half gallon of OJ or grape juice and 1 gallon of water A DAY and was STILL thirsty.
    As for my vision, I couldn't read my license plate from 10 feet away. 10 months earlier, I was 20/20.

  • Reply Vivek K May 28, 2014 at 10:47 am


  • Reply Claudio Dinapoli June 1, 2014 at 1:50 pm

    shouldn't glucose concentration in blood start to grow not since we've eaten  but since a few hours later, because absorbtion only starts in the jejunum of the small intestine, and before food gets there has to be digested for maaany minutes in the stomach?

  • Reply Karl Josol September 16, 2014 at 2:48 pm

    I took my blood sugar level in the morning before eating. It's 100. Am I diabetic?

  • Reply productreview November 29, 2014 at 10:46 am

    Do you know of any natural way you can control your blood sugar levels?

  • Reply Frances Divine Pascua September 8, 2015 at 9:46 am

    Hiyaaaa! Have you thought about the Hamilton Diabetes Reversal Protocol? (search on google) I have heard some extraordinary things about the results in lowering Blood sugars and my brother in law got cool Glucose measurementsafter trying it.

  • Reply pinaki das December 6, 2015 at 5:01 pm

    i am having fasting blood sugar level -115/116 mg/dl and post pradrial blood sugar bellow 120 mg /dl for last 3 years. do i need to start anti diabetic treatment ?

  • Reply nazma ahmed March 31, 2016 at 11:20 pm

    Thank you very helpful.

  • Reply Robin June 23, 2016 at 2:32 am

    too small to read can please make the handwriting bigger and neater and not yellow?

  • Reply Angie Tull July 26, 2016 at 12:32 am

    +anonymous person
    If It's too small………… JUST PUT IT IN FULL SCREEN!!! D:<
    PS. also he's writing it on a mouse, NO 1 CAN WRITE PERFECT!!!!

  • Reply Ransom Locke August 12, 2016 at 11:29 am

    you are wrong!! the glucose goes up for digestion the glucose in the food
     does not appear for at least four hours or until its absorbed.glucose levels are automatic
    and has NOTHING to do with a food.diabetes has NOTHING to do with a particular food.
    thanks for the video even if its wrong

  • Reply Pluto Mars October 11, 2016 at 3:29 am

    Your body doesn't need Glucose at all. In fact I am baffled that this video claimed you "will DIE"! NO! Research ketogenic diet. Ketone bodies are even a better less oxidative food for brain. Unhealthy fats are a myth. There are no essential carbs. Just have essential fats and protein.

  • Reply Josh H February 20, 2017 at 3:52 am

    pretty sure your a doctor

  • Reply Zeke Matthews May 30, 2017 at 5:19 am

    Are there any videos for those who are wanting to study ahead for paramedics course? Or can you make a few videos or a playlist for that?

  • Reply HeadRock September 26, 2017 at 1:21 am

    Its the y axis not the vertical axis

  • Reply Navin Prasath November 9, 2017 at 5:19 am

    Insulin 2hrs 75 GMs glucose
    My results 97.65
    It's noraml range r not

  • Reply Sarmed Al-Chalabi January 7, 2018 at 8:33 am

    thanks for the great video

  • Reply 2000Betelgeuse March 28, 2018 at 2:40 pm

    This same idiot again, explaining about math and glucose, people please ignore this video…consult a real expert

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