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Did you know your eyes, nails, and skin
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could be revealing important clues about
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your thyroid? Even feeling anxiety can
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be an important clue. An overactive
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thyroid is more common than people
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think, and I can often spot the signs as
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soon as I walk into a patient's room.
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So, today, I'm going to show you the top
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19 visible signs of hypothyroidism, so
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you know exactly what to watch out for.
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Your thyroid is a small butterfly-shaped
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gland at the base of your neck. But
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don't let it size fool you. It has
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powerful effects on nearly every cell in
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your body. Here's how it works. Your
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brain produces a hormone called thyroid
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stimulating hormone, which we usually
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call TSH for short, and that tells your
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thyroid to make the hormone T4. Your
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brain is constantly monitoring the
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amount of T4 in the blood and then
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adjusts the amount of TSH accordingly.
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So, if your T4 levels are too high, your
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brain will release less TSH as part of
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this sophisticated feedback loop in the
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same way that you would turn down the
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volume of your headphones if they were
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too loud. But the story doesn't end
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there. T4 then gets converted to the
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active hormone T3. You can think of T3
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like the gas pedal for your body's
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metabolism, telling your cells how fast
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to work and how much energy to burn. If
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you have too much thyroid hormone in
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your body, we call this hyperthyroidism.
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And the most common cause stems from a
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problem with the immune system. Your
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immune system creates antibodies called
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thyroid stimulating imunoglobulins that
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mimic the shape of TSH. They attach to
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the thyroid gland forcing it to produce
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more hormones and your brain loses all
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control over the process. It's like
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they've hijacked your thyroid and this
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is called Graves disease. So let's take
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a look at our first patient. This is a
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43-year-old woman with Graves disease.
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You don't need a medical degree to see
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that her eyes are noticeably bulging
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forward. And when you look at her
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profile, it makes it even more obvious.
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This is called proptosis. And it's not
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always this obvious because it happens
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slowly over the course of months to
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years. This is classic for Graves
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hypothyroidism. It turns out the
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antibodies that stimulate the thyroid
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also stimulate a special type of cell
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called fibrolasts, which create
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hyaluronic acid. Yep. the same stuff
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that's used in lip fillers and high-end
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creams to draw in water and puff up the
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skin. When this accumulates behind the
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eyes, it causes swelling of the muscles
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that control your eyes. And this slowly
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pushes your eyes forward, which you can
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see here on the CT scan. And this isn't
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just a cosmetic issue. A third of people
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with proptosis will develop double
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vision. That's because coordinating the
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movement of both eyes so that they're
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perfectly in sync is a delicate balance
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which is managed by six small muscles
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behind each eye. It's actually amazing
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when you stop to think about it because
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even just a little bit of misalignment
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will cause double vision. And if you
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leave it too long, all that swelling and
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pressure behind the eyes can become so
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intense that it can compress the optic
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nerve which can lead to blindness. Now
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swelling doesn't just happen behind the
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eyes. It can also happen around the eyes
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like we see in this patient or it can
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cause swelling of the eyelids themselves
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which can be really severe in some cases
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but it often takes months or years for
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your eyes to get to that point. But
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luckily there are some early subtle
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signs that we can test for together.
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Look in the mirror and when your face is
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relaxed check if you can see the white
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of your eye above your iris which is the
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colored part of your eye. This can
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sometimes be the earliest sign of too
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much thyroid hormone. The reason this
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happens is because the T3 hormone makes
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your body more sensitive to fight
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orflight hormones like adrenaline. So
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even if you have normal amounts of
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adrenaline in your system, your body
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responds like it's being attacked by a
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bear. And in that case, you want your
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eyes wide open. Another sign you can
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test for at home is called lid lag. But
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you'll need a partner or a video camera
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for this one. This time we're looking
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for the movement of the upper eyelid. I
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usually ask a patient to look up at my
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finger and follow it as I slowly move it
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down. Watch how Mark's eyelids moved
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smoothly and symmetrically with his
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eyes. Now compare that with this patient
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who has hyperyroidism. You can see that
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her eyelids are lagging behind, which is
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why we can see the white part of her eye
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above the iris. All right. Now, let's go
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back and look a little more closely at
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that same woman's neck. I don't think
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you need me to tell you that if you see
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dramatic pulsations like this, you need
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to see your doctor. That's her corateed
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artery. And that large pulsation of the
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corateed artery is a classic sign of an
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overactive thyroid. When thyroid
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hormones are high, the heart pumps more
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forcefully and blood vessels dilate.
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That combination leads to a hyperdamic
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circulation. And one of the most visible
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signs is that bounding pulse on the
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neck. Now, while looking at her neck,
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you may have also noticed a fullness at
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the base of her neck. This is really
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common in Graves disease where those
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antibodies target the thyroid telling it
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to grow bigger and stronger so that it
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can make more thyroid hormone. But it's
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not always this obvious. So when I'm
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looking for a goer on one of my
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patients, I'll get them to swallow some
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water and then I watch their neck to see
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if their thyroid gland is moving up and
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down. It's pretty easy to check for
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yourself. So if you're interested, I go
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over this in my other video on signs of
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an underactive thyroid, which I'll link
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up here and in the description. In that
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video, you'll also learn why a large
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goer can also be a sign that you're not
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producing enough thyroid hormone. Now,
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sometimes your thyroid can become so
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large that it can extend down your neck
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and into your chest. And the main issue
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is that it can compress the large veins
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that drain blood from your head. There's
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a very simple test we can do to check
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for this called Peton sign. Just raise
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your arms up above your head like you're
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about to dive into a pool and wait. This
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is what we're watching for. Notice how
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this man's face and neck are turning red
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as the veins are being compressed. Then,
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as he puts his arms down, the redness
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goes away as the blood is able to drain
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out of his head. Here's another example
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of a 36-year-old man doing this test.
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You can really see how the neck veins
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are bulging. This patient went on to
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have an MRI first with his arms by his
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side, and here you can see the massive
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goer extending down into his chest. Then
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he had a second MRI with his arms raised
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above his head. You can clearly see that
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his external jugular veins are
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completely blocked. It's actually a
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remarkable image. Just remember,
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anything that causes obstruction in this
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area can lead to this sign, including
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cancer. So, it's something you never
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want to ignore. All right. Now, let's
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switch gears and look at your
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fingernails. They're constantly growing
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through a complicated, energyintensive
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process. And as a result, changes in
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your health can often show up in your
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nails. And hyperthyroidism is no
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exception. See how the nail seems to be
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peeling back and separating from the
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skin underneath? The general term is
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anolyis, but in hyperthyroidism, we'll
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often call it plumber's nail. It's
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painless. And if it's your ring finger
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that's affected first, it could be a
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clue that it's related to hyperyroidism.
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Exactly why the nail starts to separate
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is unknown, but it's likely something to
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do with accelerated nail growth. All
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right, next I've got another test for
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you to try on yourself. Put your nails
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together like this. Can you see a
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diamond shaped gap between the base of
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your nails? If you can, that's normal.
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But if you can't and your nails look
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like this, it's called clubbing. When I
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see clubbing of the nails, I'm usually
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hunting for issues with the heart,
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lungs, or liver. But it's important to
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know that hyperyroidism is another
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cause. And along with clubbing, you'll
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also see other distinct features in the
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hands. This is a 56-year-old man with
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Graves disease. And the first thing that
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stands out to me is the unusual shape of
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his fingers. They look thick, and the
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X-ray explains why. Look closely at
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where the yellow lines are pointing.
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Notice how the edge of the bone looks
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kind of fuzzy. That's abnormal bone
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growth. Once again, those antibodies in
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Graves disease have stimulated
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fibroblast cells. This time around the
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bone leading to inflammation, swelling
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and new bone formation. This is called
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thyroid acropache which comes from the
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Greek word for thickening of the limbs.
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And as you can see, this can lead to
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really profound deformities of the
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hands. Of course, we want to catch it
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before your hands start swelling. And it
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turns out your hands are a great place
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to look for a subtle but early sign of
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hyperyroidism, namely a postural tremor.
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And here's how you check for it. Just
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extend your hand and your fingers out
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like this and look for any shaking of
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the fingers. One trick is to put a sheet
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of paper on top of your hands, which
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makes it a lot easier to spot a fine
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tremor. This type of tremor is
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noticeable when you're doing something
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like writing, and then it tends to go
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away when you're at rest. It's the same
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type of jittery tremor that you can get
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if you drank a whole bunch of coffee. It
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just never goes away. And this happens
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because the thyroid hormone is basically
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revving up your nervous system. So,
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you're always in that fight orflight
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state. Okay. Next, I've got a great case
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to share with you. This is a 35-year-old
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man who grew these firm, painless lumps
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on his shins over the course of 7
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months. If you look closely, you'll
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notice tiny dimples where the hair
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follicles open. Those pits look a lot
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more prominent because of the thick waxy
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swelling underneath the skin. And we
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described this as podorange because it
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kind of looks like the texture of an
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orange peel. His doctors took a skin
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biopsy and confirmed the diagnosis. This
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is pre-tibial mixadema, a classic skin
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finding in Graves disease. And this is
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caused by the same process we talked
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about before. Antibodies stimulate
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fibroblasts which cause swelling. But
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pretubial mixadema doesn't always show
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up as lumps. More often than not, it
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shows up as red violet plaques of firm
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swelling on the shins. Now, this might
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look severe to you, but it can actually
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evolve into something far more dramatic.
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Take a look at this. It's called
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elephantasis. Now, elephantiasis is
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usually caused by parasites blocking
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lymphatic drainage. And it's something
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you typically see in tropical countries,
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but rarely we see this in Graves disease
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when hyaluronic acid builds up and
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blocks the flow of lymphatic drainage.
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And this extreme thickening and
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distortion of the skin starts to make it
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look like the foot of an elephant, which
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is how it got the name. Okay, now let's
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talk about what excess thyroid hormone
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does to your internal organs. When your
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body is flooded with thyroid hormone,
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it's like hitting the gas pedal on your
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body's metabolism, and every organ is
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affected in its own unique way.
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Unintentional weight loss is a common
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symptom. Despite eating more than usual,
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the energy demands of the body are just
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too high to maintain your weight. And
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unfortunately, a major component of that
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weight loss is from muscle loss. Thyroid
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hormones increase protein breakdown and
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they also suppress muscle regeneration.
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And classically, it's the proximal
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muscles in the shoulders and hips that
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are most affected. So, I usually hear
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patients telling me that they have
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difficulty climbing stairs or even
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washing their hair. That high metabolism
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will also make you feel like you're
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overheating. To deal with this, the tiny
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blood vessels at the surface of your
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skin will dilate to radiate heat out of
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your body, and you'll also start
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sweating more. So, someone with
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hyperyroidism typically will have warm,
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moist skin. You know, sometimes I see
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people walking around in the winter with
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shorts and a t-shirt on, and it always
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makes me wonder, are they just more
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Canadian than I am, or do they actually
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have hyperyroidism? Your heart is also
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affected. Your smartwatch may tell you
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that your heart rate is faster, or you
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might start feeling pounding in your
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chest, and that's because your body is
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primed in that fight orflight state.
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Palpitations on their own once in a
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while are often harmless. But an
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overactive thyroid significantly
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increases your risk of developing an
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arhythmia called atrial fibrillation.
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And a lot of people don't realize that
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this irregular heartbeat dramatically
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increases your risk of having a stroke.
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And fortunately, we have good treatments
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to prevent that from happening. You'll
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also notice that your hair grows more
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quickly and your scalp becomes more
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oily, but it actually grows so fast that
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the hair quality is poor, making it more
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thin and fragile and more prone to
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falling out. Your bones lose their
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density, becoming more brittle and
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leading to osteoporosis. For some older
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patients, we only figure out that they
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have hypothyroidism after they fall and
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break a bone. Hypothyroidism can also
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mimic an anxiety disorder with symptoms
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of irritability, feeling on edge,
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difficulty sleeping, and panic attacks.
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That's why if someone all of a sudden
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has new onset anxiety out of nowhere,
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I'm always thinking about checking the
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thyroid. The impact on the brain might
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surprise you. Sometimes a little
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adrenaline can sharpen your senses and
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make you perform at your best. But when
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you're ramped up all the time from
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hyperyroidism, the opposite is true.
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Young people with hyperyroidism will
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often have difficulty focusing and
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studies have shown that they score lower
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on cognitive testing compared to healthy
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controls, but the cognitive impact on
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older adults is far worse and they often
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present with symptoms like confusion
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that can be confused with dementia.
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Clearly, there are a lot of signs and
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symptoms that can point to an overactive
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thyroid. But how do we actually make the
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diagnosis? Well, diagnosing
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hypothyroidism is based on blood work.
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In general, your thyroid hormones called
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free T3 and free T4 will be elevated
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while your TSH will be low, which makes
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sense because when your body has too
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much thyroid hormone on board, your
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brain is trying to reduce any further
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production. One really important tip, if
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you're taking a biotin supplement, which
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is vitamin B7, it can interfere with
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certain lab tests, leading to false
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results. Biotin can make it look like
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your TSH is low and your free T3 and T4
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are high. In other words, your test
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results will look like you have
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hyperthyroidism even when your thyroid
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is completely normal. So, always tell
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your doctor what supplements you're
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taking and stop taking biotin at least 2
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days before your thyroid blood tests.
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Now, if your blood tests are consistent
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with hypothyroidism and you weren't
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taking biotin, the next step is
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searching for the underlying cause.
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Sometimes the physical exam findings are
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so classic for Graves disease that it
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can be easily confirmed by testing for
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those antibodies in the blood. But when
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the cause is less clear, it can be
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helpful to order an ultrasound or a
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special test called a radioactive iodine
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uptake scan. Now, this is a really cool
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test because it sort of gives us a heat
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map of how active your thyroid is. And
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it all comes down to the fact that it
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takes a lot of iodine for your body to
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create thyroid hormones. Here's how it
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works. Your doctor will get you to
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swallow a pill that contains a tiny
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amount of radioactive iodine. Not enough
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to hurt you, but just enough for a
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special scanner to detect the radiation
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it's giving off. 24 hours later, the
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scanner checks how much of that iodine
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your thyroid has absorbed. If it's
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taking up a lot, that tells us the gland
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is working overtime. And we can take
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images to see what parts of the thyroid
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are actively using the iodine. Most
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commonly, it's Graves disease where the
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whole thyroid is overactive. Although it
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could also be a toxic adenoma where one
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spot is hyperactive or a toxic
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multi-nodular goer where there are
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multiple hyperactive spots or
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thyroiditis which just means there's
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inflammation of the thyroid from any
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number of causes from medications to an
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infection. But regardless of the cause,
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getting your body out of that fight
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orflight state can help with symptoms
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immediately. We almost always give beta
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blockers like aol or mettopriol which
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are medications that block the
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adrenaline receptors and that can
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rapidly bring your blood pressure and
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heart rate back to normal and improve
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symptoms like anxiety, insomnia and
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tremor almost immediately. That helps
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with symptoms but it doesn't actually
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bring down thyroid hormone levels. For
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that the treatment depends on the
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underlying cause. Medications can help
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to block thyroid hormone production, but
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sometimes at least part of the thyroid
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needs to be removed surgically or
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destroyed using radiation. If you
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enjoyed watching this video, I'd suggest
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watching this one next on
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hypothyroidism. Then you can see what
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the effect of having too little thyroid
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hormone is on your body. Stay curious,
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stay healthy, and I'll see you in the
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next video. So, bye for now.
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[Music]
