If you’re suffering from hypothyroidism, or think you
might be, it’s important to know that a thyroid conversion problem may be a hidden
cause… and that conversion issues can’t always be solved with a prescription medication.
Low thyroid symptoms,
such as fatigue, weight gain and sensitivity to cold, can appear when your body
has difficulty converting the thyroid hormone T4 (thyroxine) into our most active
thyroid hormone T3 (triiodothyronine), which does the vast majority of thyroid work.
That conversion runs smoothly when everything’s in good shape, but unfortunately,
there can be problems with that process.
Most doctors don’t know how to manage T4 to T3 conversion problems
When your thyroid is low enough that your doctor gives you a prescription for your
condition, it’s almost always in the form of Synthroid, Levoxyl, or the generic
version of those drugs — levothyroxine.
However, all of those drugs are just T4, and your doctor is prescribing them based
on the assumption that T4 is going to convert to T3 in your body.
Most doctors believe this. It’s in medical textbooks and guidelines. And it’s true
that in a healthy system, levothyroxine will help your body produce T3.
But there are numerous problems that can interfere with that conversion of T4 to
active T3. If you’re making or taking T4 and it can’t get to T3, you simply can’t
benefit from it. It’s like being all dressed up with nowhere to go!
Most conversion issues are reversible
Here’s some good news: all of the factors that can interfere with the production
of active thyroid hormones are reversible, except for one. The vast majority of
women will be able to turn these around and eventually not need, or be able to get
off, thyroid hormone.
The number one factor that interferes with a T4 to T3 conversion is poor health.
Any chronic illness, whether it’s an autoimmune disease, chronic infection, diabetes,
insulin resistance, chronic fatigue syndrome, fibromyalgia or just about any another
chronic condition, has the potential to interfere with T3 activation.
If this is the case for you, I really encourage you to work with your doctor or
healthcare practitioner on that chronic condition to turn it around.
7 natural ways to reverse thyroid hormone conversion issues
1. Avoid crash dieting, which harms your metabolism
You’ve probably already heard about how crash dieting slows your metabolism way
down. That’s because the body starts to think you’re starving. It doesn’t know that
you have food in the fridge, so it senses real danger and slows down your metabolism.
Your body does that by reducing your production of T3 from T4 to the point where,
once you go off a crash diet, your metabolism is often so slowed down that you’ll
actually require 500 or 600 calories less to maintain your weight once you go back
to a regular diet. It can take the body a long time to reestablish your old norm
— essentially, to trust again.
There are a lot of reasons to avoid crash dieting, but this is a big one.
2. Reduce inflammation
Inflammation is another big interfering factor in that conversion of T4 to T3.You
may be aware that you have inflammation because you have the classic symptoms of
pain, redness and swelling. Or, you may have low-grade inflammation with symptoms
that are less obvious.
Inflammation can stem from chronic infections in the body, or from eating a standard
Western diet that is high in flour products and sugar. Things like soft drinks,
too many animal proteins, trans fats, or processed, fried, and fast foods all increase
low-grade inflammation in the body.
You can also have inflammation from excess abdominal fat, because the fat that concentrates
in the abdomen more easily churns out inflammatory cytokines, which are the mediators,
or messengers, of inflammation. These cytokines directly inhibit the conversion
of T4 to T3. If you have infections, which are often hidden, it’s important to get
help resolving them. For instance, you could have an infection in the stomach from
Helicobacter pylori or other “gut bugs” in the intestine, or Lyme disease, or a
periodontal infection, which can be asymptomatic.
3. Eat an anti-inflammatory diet to prevent thyroid issues
Eating an anti-inflammatory diet will help move out those foods that cause inflammation.
- Emphasize lots of colorful fruits and vegetables. They’re packed
with compounds such as antioxidants that fight inflammation, and they’re also alkalizing.
Eating sugar, white flour products, and a meat-rich diet makes our bodies acidic,
which is directly correlated with inflammation. When we alkalize, it does the opposite
— all that inflammation just calms right down.
- Include clean proteins and healthy fats, which are not the trans
fats from fried foods but rather fats like olive oil, coconut oil and cold-water
fish, which are packed with healthy monounsaturated or omega-3 fatty acids.
- Consider an
omega-3 fatty acid supplement.
- Eliminate reactive foods. Anything that causes an immediate allergic
reaction (anaphylaxis in the extreme case) should obviously be avoided, but there
are also many food sensitivities that can give us problems. Those immunogenic foods
may trigger delayed reactions or symptoms, making it hard to pinpoint what’s causing
- Try an elimination diet. If you’re not sure what foods, if any,
are giving you trouble, then you should meet with your health care practitioner
to get some help. An elimination diet and gradual reintroduction of foods can help
you identify foods that are causing inflammation in your body every time you have
an immune reaction to them.
4. Get serious about stress management for healthy cortisol
The T4 to T3 conversion requires some degree of cortisol, the adrenal stress hormone,
which is produced in response to stress and low blood sugar. That means that cortisol
insufficiency, or not having enough cortisol (which can happen with chronic stress)
can then cause you to have low thyroid function.
The hypothalamic-pituitary-adrenal axis, or HPA axis, is the feedback system between
the brain (which contains the hypothalamus and pituitary gland) and the adrenal
glands, which lie on top of the kidneys. With chronic stress, the signals between
the brain and the adrenal glands can be disrupted to the point where the body no
longer produces enough cortisol. That can lead to low thyroid function on top of
You’ve heard it ad nauseum: “Manage your stress,” to the point where you may be
immune to the words. Still, it’s important to remember that even if your mind gets
used to a frantic pace, and you’re convinced you have to keep operating at that
pace — even if you can fool your brain, your body never learns how to adapt to that
pace. When our bodies can’t keep up, we ultimately pay the price. That’s why I strongly
encourage you to manage the stress in your life, even if everybody else is running
at top speed and it feels abnormal to go slower. It’s more important that you get
adequate sleep and start taking extra good care of yourself.
Too much cortisol can also interfere with the conversion from T4 to T3. That can
stem from acute emotional stress, or it can be related to physical, or physiological,
stress. Infections, inflammation, allergies, hypoglycemia, or pain syndromes — even
simply pain, alone — can all be factors that cause cortisol to surge.
5. Rethink low-carb diets
The T4 to T3 conversion also requires a certain amount of insulin, which is released
by the body when we consume carbohydrates. Many people think of “carbohydrates”
as a bad word these days, but there are good carbs and bad carbs, and we’re all
different in terms of how well we tolerate certain foods. For example, some people
can’t handle an extremely low-carb diet, and their insulin level may drop so low,
as a result, that thyroid function is affected.
Just because a high-protein, low-carb diet is all the rage these days, that doesn’t
necessarily mean it will work for you. If you feel bad on that diet, take your experience
to heart and take care of yourself. You might want to get some help looking into
the kind of diet that will work best for you. It could be that taking in some complex
carbohydrates like beans, legumes, and some whole grains, which are very different
from the simple carbohydrates in sugar and white flour products, can help keep your
blood sugar stable and assist with insulin release.
Conversely, too much sugar in your diet can interfere with T4 to T3 conversion.
If we eat a bunch of sugar and it pours into the bloodstream, we get a big spike
in blood sugar (glucose). This can then cause the pancreas to overshoot when it
produces insulin in response. That in turn causes your blood sugar to crash. One
of cortisol’s functions is to help raise blood sugar when it’s too low. So, if you’re
experiencing wild rollercoaster spikes in glucose and insulin, cortisol can overshoot,
and you’ll be back to cortisol excess and interference with the production of active
6. Check your minerals
a cofactor for the enzyme that converts T4 to active T3. If you’ve had a poor diet
for a while, especially if you’ve had gastrointestinal problems like digestive or
absorption issues, you might be low in selenium and a number of other minerals.
I recommend to people that they take a high quality multivitamin/mineral, along
with a healthy diet.
If testing confirms that you have elevated thyroid antibodies suggesting Hashimoto’s
disease (chronic lymphocytic thyroiditis, which often leads to hypothyroidism),
then I also recommend a selenium supplement daily. Be careful not to take too much
selenium, though — 200 micrograms is a safe dose. There’s some evidence that selenium
can help reduce those antibodies, and it helps the enzymatic conversion of T4 to
Another consideration is iron deficiency anemia. Fatigue and hair loss are two possible
symptoms of iron deficiency, but those are also common symptoms of low thyroid function.
If you’ve had chronic digestive problems like low stomach acid or small intestinal
bacterial overgrowth (SIBO), or especially if you’ve had a loss of blood over time,
whether it’s from menstrual periods or some condition that’s caused bleeding, consider
the possibility of iron deficiency. It’s very easy to check your iron status.
7. Avoid toxic chemicals
Certain medications can also interfere with the production of T3. For example, beta-blockers,
especially propranolol, which is often given for hypertension, can interfere. Perflourinated
compounds, which compose part of the nonstick surfaces on products like Teflon pans
or the linings of microwave popcorn bags, can also interfere. Other examples include
toxic compounds in cigarette smoke and smog, bisphenol A (BPA), and phthalates,
which can be found in plastic containers, perfumes and personal care products. Some
non-organic fatty foods are disruptive, as are toxic metals such as mercury, lead
It’s impossible to avoid every chemical these days, of course, but there is a lot
we can control. For example, buy organic produce. It can be easy to ignore the organic
section in the store, especially if organics are more expensive, but the non-organic
foods are the ones containing the pesticides. Healthier choices also include chemical-free
meats and wild-caught fish. It might sound like the quality of farmed fish would
be better controlled, but farmed fish is surprisingly toxic.
You should also store your food in glass containers instead of plastic, especially
fatty foods, because the fat in the food can easily draw in chemicals from the container
or wrapping. Use non-Teflon pans for cooking, and store your drinking water in glass
water bottles instead of plastic. There’s a lot we can do to live as cleanly as
possible in this increasingly polluted environment we live in!
There’s no one-size-fits-all answer
Lastly, there can be genetic variation in the enzyme that converts T4 to T3, just
like there’s genetic variation in every other function in the body. We’re all unique,
which is why one protocol doesn’t work universally in everyone.
One British study looked at 552 subjects with hypothyroidism, specifically at one
particular mutation in a deiodinase enzyme that converts T4 to T3. Researchers found
that a whopping 16% of those individuals had a mutation that slowed down that conversion.
All of them had been on T4 medication. When they were given T4 plus T3, their symptoms
As far as I know, the test for that mutation is not commercially available. But
I bring it up because it drives home the reminder that we’re all different. Your
doctor may be treating you according to a standard of care and expect you to be
able to respond like the textbooks promise you will. But if you’re taking T4 and
it’s still not working for you, even at a higher dose, then talk to your doctor
about the idea of switching to a product with combined T4 and T3, such as Westhroid,
Nature-throid, or Armour.
Or, if some of the other factors we’ve discussed here are relevant for you and you
have a more significant conversion problem, it might be useful to take a compounded
T3 product, which contains more T3 than you’d get in those other products. There’s
even a time-release T3 that may be a safer way to go — there are many different
options. Again, the whole point of these alternative hormone prescriptions is to
bypass that potentially troublesome conversion step, to make sure you’re getting
the T3 that you need.
As you can see, there are many different factors that can interfere with this function
that our bodies were designed to carry out. The good news is that, with the exception
of genetic variation, getting hung up at T4 and not making enough T3 is reversible.
If any of these factors I’ve discussed are relevant for you, and you address them,
you’ll likely experience a boost in your thyroid function.
If you’re already taking Synthroid or levothyroxine (T4), but not benefitting from
it, talk to your doctor about possibly adding in some T3 and seeing what that does
for you. Feeling better from such a change can be diagnostic in itself, indicating
that a conversion problem is real for you.
Finally, if you are taking prescription thyroid medication but also starting to
address some of these factors that are relevant for you, keep in mind that your
thyroid function will be gradually improving along the way. What this means is that
over time you might not need as much thyroid medication, and, at some point, need
no prescription at all. It’s therefore important to monitor your thyroid markers
along the way through your health care practitioner. You don’t need to do it more
often than every few weeks, because it takes time for the body to adjust. If you
do monitor them, you might just find that you can get off thyroid hormone completely.
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