Your thyroid will tell you when something is wrong.
The only problem is that most people miss the signs.
Why?
Because a low thyroid doesn’t show up as one dramatic symptom that pops up out of nowhere. Instead, it’s a small handful of subtle signs that are scattered across different areas of your body.
And every single one can be easily explained away by itself:
Your high cholesterol? That’s your diet. The numbness in your hands? That’s from typing all day. The changes in your voice? That’s you just getting older.
Or so your doctor will say. But I say something different.
Here are 6 sneaky signs your thyroid is trying to tell you it has a problem and an explanation for why they get missed:
#1. Unexplained High Cholesterol
Has your cholesterol been slowly rising without an obvious cause?
This is a classic sign of hypothyroidism, and one that is often missed.
Here’s why:
Your liver clears LDL cholesterol out of your blood using receptors that sit on the surface. Your thyroid controls how many of those receptors your liver makes[1]. When your thyroid drops, there are fewer of the receptors to clear your cholesterol, which causes it to rise.
That part is pretty simple.
What’s not simple is figuring out the cause.
Because high cholesterol is so common and because it’s almost always related to poor lifestyle (diet and exercise), doctors aren’t typically in the habit of linking high cholesterol to thyroid dysfunction.
As a result, when your doctor sees high cholesterol in your labs, you are told to start a statin and to stop eating red meat.
But that was never the underlying cause; it was always your thyroid.
In addition to high cholesterol, you might also see the following changes:
- A rise in apolipoprotein B
- Higher triglycerides
- Numbers that don’t respond the way they should to diet changes
If you are seeing unexplained changes to your cholesterol, think thyroid.
#2. A Body Temperature Below 98.2
Your thyroid is like your body’s thermostat, and it sets how much heat you produce at rest[2].
When your thyroid slows down, it takes your body’s heat along with it.
A healthy body temp should run at least 98.2 degrees, but having a thyroid problem can drop it by a full degree or more.
It’s easy to miss a low body temp if you aren’t checking for it, but you won’t miss the symptoms.
You’ll feel this drop as being cold, even in the summer, or the need to wear socks to bed at night.
The best way to determine your body temperature is to check it.
Here’s how:
- Take your temperature first thing in the morning, before you get out of bed
- Use the same thermometer every time
- Do it for five days in a row
- Average the five readings together
#3. A Resting Heart Rate Under 60
Having a low resting heart rate is good, right?
Yes, but only if you are a conditioned athlete.
If you are overweight or don’t exercise, having a low resting heart rate is a sign that your thyroid may be in trouble.
Your thyroid is responsible for setting your resting heart rate, similar to how it impacts your resting metabolism[3].
If you are healthy and active, your heart rate will be low and your metabolism will be high.
If you have a thyroid problem, both your heart rate and your metabolism will be low.
The key is thyroid function.
You need lab tests to assess thyroid function accurately, but you can get a lot of information by checking your resting heart rate first thing in the morning or overnight.
If you have a wearable device that shows your heart rate is in the 50s or 60s and you know that you aren’t as active as you should be, this is probably a sign you need labs to check your thyroid.
The numbers get even more convincing if you see a low resting body temperature along with a low resting heart rate.
#4. Numb or Tingling Hands at Night
Many people wake up in the middle of the night with tingling hands.
The name for this is carpal tunnel syndrome.
And the most common cause is repetitive-use injury like typing all day.
But another cause is low thyroid function.
When your thyroid is low, fluid can build up in the tissues around your wrist, which puts pressure on the median nerve.
This is exactly why thyroid patients have a higher rate of carpal tunnel syndrome compared to those without it[4].
Most doctors recommend a wrist brace, and while this may help some people, it won’t help you if your thyroid is responsible.
The real solution is to fix your thyroid.
#5. A Changing Voice
The same fluid that builds up in your wrists can build up in your vocal cords, and when it does, it changes how they vibrate.
Practically speaking, this changes how your voice sounds.
Most people will miss this unless they use their voice professionally, but it’s an early sign something is wrong with your thyroid.
Research shows that having a thyroid problem changes the pitch of your voice and adds roughness to it[5].
If your voice is lower than it used to be, especially at the end of the day, think thyroid problem.
This one is hard to spot because it can be subtle, but one of the best ways to confirm vocal changes is with comparison.
You can listen to a recording of your voice from several years ago and compare it to how it sounds now.
#6. Weight That Goes On and Never Comes Off
This is one you won’t miss.
Thyroid patients gain weight over the holidays and on vacation, just like everyone else.
The difference is what happens afterward because that weight never comes off.
As a result, the scale keeps slowly creeping up, year after year, until you’re 20 pounds heavier than you used to be.
The problem is that it’s easy to blame weight gain on just eating too much of the wrong foods, but that’s a sloppy excuse.
The way to tell the difference between thyroid-related weight gain and unhealthy eating is how responsive you are to weight loss.
If you clean up your diet and the scale won’t budge at all (or it’s much slower than expected), think thyroid problem.
One thing worth knowing before you get your hopes up is that fixing your thyroid problem with medication doesn’t automatically reverse the weight.
Studies show that thyroid patients who start levothyroxine experience little to no weight loss, even though they need it[6].
Fixing your thyroid is important for putting your body in a position to lose weight, but it won’t happen without effort on your part.
What To Do Next
None of these signs proves that you have a thyroid problem by itself.
But together, they create a pattern, and a pattern is what your doctor should be looking for.
Unfortunately, doctors tend to miss thyroid problems, which is why it’s important for you to know this.
To make it easy on you, I’ve created a number of free resources that can help.
My recommendation is to start with my free optimal thyroid lab test calculator.
If you have thyroid labs handy, plug them into the calculator, and it will tell you if there is a problem.
If you don’t and you have these symptoms, go and get your labs checked and come back to use it. It will be waiting for you.
Scientific References
1. Duntas, L.H., et al. (2002). Thyroid disease and lipids. Thyroid. doi:10.1089/10507250252949405.
2. Tsibulnikov, S., et al. (2020). Thyroid hormones and the mechanisms of adaptation to cold. Hormones (Athens). doi:10.1007/s42000-020-00200-2.
3. Udovcic, M., et al. (2017). Hypothyroidism and the Heart. Methodist DeBakey Cardiovascular Journal. doi:10.14797/mdcj-13-2-55.
4. Abuzinadah, A.R., et al. (2025). Effect of Hypothyroidism on the Risk of Carpal Tunnel Syndrome and Electrodiagnostic Parameters. Neurology International. doi:10.3390/neurolint17090150.
5. Ersoz Unlu, C., et al. (2022). Acoustic and perceptual voice parameters in subclinical and overt primary hypothyroidism. Auris Nasus Larynx. doi:10.1016/j.anl.2021.09.003.
6. Lee, S.Y., et al. (2014). Changes in body weight after treatment of primary hypothyroidism with levothyroxine. Endocrine Practice. doi:10.4158/EP14072.OR.
