They prescribe Statins at a high rate, significantly more than thyroid prescriptions. Yet, low thyroid function is contributory, if not causal, in driving cholesterol higher.

Thyroid Intro
Thyroid hormone metabolism is complex and vital.

Our DNA has thyroid-binding sites, and when bound directs metabolic performance. Insufficient thyroid leads to decreased metabolism. TSH (thyroid-stimulating hormone) is the entry-level test for thyroid, but it does NOT tell the whole story. T4 is inactive, it gets converted to T3 which is active. But there is also reverse T3, which acts as a thyroid braking system in times of stress so we don’t burn through all our energy.
Thyroid And Cholesterol
Thyroid hormone is critical in cholesterol metabolism. Cholesterol metabolism is also complex, definitely way beyond a lab value for “bad cholesterol”. Have a look at a 100-page paper I put together recently on Statins and Heart Disease.
Put the two together and we have to resort to pictures:
Thyroid Upregulates LDL Receptors
They refer to LDL as “bad cholesterol”. LDL receptors (shown above as LDL-R) present on the cell surface and grab LDL from the bloodstream – resulting in less LDL on your lab test. T3, the active form of thyroid, encourages more LDL-R. T3 also protects us from oxLDL which is an oxidized/damaged form that is of greater concern to precipitate heart disease. [NOTE]HTTPS://WWW.NCBI.NLM.NIH.GOV/PMC/ARTICLES/PMC3109527/[/NOTE].
Statins inhibit cholesterol synthesis. Less cholesterol production leads to more LDL-R expression. Supply/Demand. LDL-R expression is the main mechanism that explains statins impact on LDL lab values.
We have a newer class of cholesterol medications called PCSK9 inhibitors. PCSK9 takes part in breaking down the LDL-R. PCSK9 activity receives influence from supply/demand and genetics. We give these EXPENSIVE (~$1k/month) drugs to slow this breakdown and keep LDL-R’s pulling cholesterol out of the bloodstream.
TSH (the common thyroid test) increases as thyroid function decreases – it is a voice yelling for help when things aren’t going well. A study showed TSH and PCSK9 activity are linked2. The worse your thyroid function, the less LDL-R’s, and the higher your cholesterol.
Thyroid Also Reduces Bad Cholesterol Outside of LDL-R
Another study examined if thyroid was impacting anything outside of the receptors. They took mice bred without LDL-R and showed a significant cholesterol reduction with thyroid replacement therapy3.
This makes sense as cholesterol and thyroid are so involved throughout the body. As your metabolism decreases, your cholesterol increases.
Improve Thyroid Before Rx’s For Cholesterol
Yes, we can give thyroid medication. But, before going down that road, supporting thyroid health is step one. Supplementing thyroid without addressing steps in this section may not result in positive outcomes.
Here are a few items to focus on. This is NOT a complete list, but a great starting point.
Fluoride Elimination
No, your teeth won’t fall out.
Fluoride was an overactive thyroid treatment in the 1950s. Now we pump that same drug into our water and toothpaste supply.
What about your teeth? Weston A. Price showed in the 1930s that the main driver of cavities and decay was sugar and flour – processed foods. He went around communities and compared regions that had access to newer processed foods and nearby ones that did not. Communities that substituted these for natural foods to their respective regions developed awful dental disease – fluoride not a factor. The image below is from his book, I can’t recommend it enough.

Iodine is a halogen in the periodic table of elements. The thyroid has a high affinity for halogens as iodine part of the thyroid hormone. Fluoride is also a halogen. Other halogens are chlorine and bromine. Watch out for swimming pools and hot tubs, your thyroid may suffer consequences of chronic use.
Avoid fluoridated water and toothpaste. Begin saving your thyroid today.
Plastics
Bisphenol-A (BPA) and Phthalates are chemical compounds that appear in solvents, plasticizers and common household products. We also find BPA in the lining of canned foods. They are everywhere.
Researches have found associations between urinary levels and thyroid function4. BPA specifically, besides its estrogenic properties, can antagonize thyroid receptors5.
Avoidance is the best policy, but obviously not entirely possible. Choose non plastic and non BPA lined cans – especially in heat exposure situations.
Sweating appears to be the best way to encourage excretion of BPA – either by sauna, exercise, or both6.
Gluten
We know gluten is a factor in autoimmune conditions. One mechanism is by contributing to leaky gut (see additional articles I have written on this topic). Gliadin, a protein component of gluten, activates zonulin which creates separation between the cells lining your GI tract7. Roundup (glyphosate, see previous articles here) also triggers zonulin – buy organic when possible. Yes, its as gross as it sounds. Right behind your GI tract your immune system is there monitoring. As more stuff gets thru, the more active your immune system is – sometimes thats good, too much, not so.
Restore is a supplement shown to help repair leaky gut, even in the presence of gliadin and glyphosate.
But with thyroid its much worse.
Gliadin looks like transglutaminase, an enzyme specifically abundant
in the thyroid. The body’s antibodies attack both the gliadin and transglutaminase8. Therefore, the immune system targets the thyroid at a high level.
Gut
Building on the leaky gut issue above, the story continues. T4 (inactive thyroid) converts to T3 (Active) by gut bacteria, at least in part. As our gut bacteria (microbiome) get damaged from antibiotic exposure and Roundup/glyphosate (also an antibiotic by patent9), thyroid dysfunction increases1011.
Chronic Inflammation
Inflammation and gut dysfunction often go hand in hand. Chronic inflammation can also impair thyroid. Inflammatory mediators called cytokines alter thyroid function12. Chron’s disease is a condition that combines chronic inflammation with gut disturbances, and it degrades thyroid performance13. Chronic Fatigue Syndrome also manifests with low thyroid14.
If you are a chronic ibuprofen consumer, odds are you have chronic inflammation. But, it can still persist without obvious symptoms.
Chronic Stress
Chronic stress is everywhere. This puts our body in a state of fight or flight – running from the tiger. Resources move from normal functioning to support this heightened stress. Thyroid signaling is an area affected. TSH, and other hormones, become suppressed. Less TSH, less thyroid.
Beyond the production signal from TSH, stress reduces the conversion of T4 to T315.
Nutrient Deficiencies
From the production of thyroid hormone to the conversion from inactive to active (by enzymes called deiodinases), we need sufficient levels of certain nutrients.
- Zinc is important for many aspects of thyroid function including DNA binding and T4-T3 conversion. Meats are an excellent source of zinc. Whole grains and beans/legumes have zinc too, but they also contain anti-nutrients called phytates that bind to zinc and other nutrients rendering them unavailable for absorption. High whole-grain consumption will probably lead to zinc and magnesium insufficiencies. Research suggests that we will absorb approximately 20 percent more zinc and 60 percent magnesium from our food when phytate is absent16.
- Selenium is an antioxidant critical in the metabolism of T4 to T3. It also can reduce thyroid antibodies 40%17. Brazil nuts are a good source, but supplementation is probably the best for those with thyroid deficits.
- Tyrosine is an amino acid, part of the chemical composition of thyroid hormone. Tyrosine is also the precursor to dopamine formation. Dopamine, the reward chemical, is helpful for focus. Meats are a good source but supplementation is an option as well, especially if you have trouble focusing!
- Iron deficiency cause problems in thyroid metabolism as well. Red meats are a great source, but I don’t recommend supplementing unless lab tests confirm you are low. High iron is a factor in chronic disease. Enter goldilocks.
This thyroid complex is a great starting point for thyroid support, it has all these except iron.
Thyroid Replacement
If poor thyroid function is an issue in cholesterol, what about taking thyroid replacement?
Levothyroxine (t4) is the top-selling prescription18. However the stats are a little misleading when totaling up all the different statins, they almost double the levothyroxine (217M to 114M Rx’s). So, thyroid replacement is popular, but not as much as taking statins. How do the two relate?
This leads me to analyze dispense data from Island Drug. If my assertion that proper thyroid function helps our cholesterol labs, then we should see some correlation in prescription data.
Hang on to your jaw, I know mine was sore from hitting the desk…
How many statin patients are on levothyroxine?
I looked at over 1600 patients on statins, 87% were NOT levothyroxine users.
How many levothyroxine patients were on statins?
70% of patients who had levothyroxine prescriptions did NOT have statin prescriptions. Maybe because they had better thyroid support?
How many T3 patients are on statins?
We saw above that T3 leads to more LDL-R expression and less LDL in the blood. Also, opportunities for T4 to T3 conversion challenges abound. Levothyroxine may not help in all cases.
Supplementing with T3 is less common. It has a short half-life and is a little harder to fine-tune – few docs have experience prescribing and managing. Preparations available are mixed T3/T4, T3 by itself, and we can compound sustained-release T3. I have seen many benefits from adding T3 to a thyroid regimen.
95% of patients with a T3 preparation did NOT have a statin in their profile.
Why More Statin Than Thyroid Prescrptions
It’s NOT your doctor’s fault.
Doctors follow the treatment guidelines based on lab values. If you pass a certain threshold on the lab, you proceed to the recommended treatment. So, let’s look at the labs.
Reference ranges are bell curves of what encompasses most people – typically 95% of the population. Problem is, if most of the population is getting sicker, the reference ranges will move that direction.
Cholesterol Labs
The National Cholesterol Education Panel (NCEP) issues guidelines called ATP (Adult Treatment Panel. Let’s look at the changes over the years:

They started with LDL less than 130 mg/dL and now want it as low as possible for some, even beyond 70 mg/dL. With goals that low, the number of people they target for statins increases every iteration of the ATP. Now, there is even a push to “drive LDL as low as possible” with “no lower limit”20. I have many concerns on this approach, which you can read about here.
Thyroid Labs
TSH is the main test used in diagnosis for thyroid. Contrary to the cholesterol approach, tolerance for suboptimal thyroid function is baked into the broad reference range of 0.45-4.5 μIU/mL.
They have found Levothyroxine to exert a beneficial effect on atherogenic lipid profile and impaired vascular function in patients with TSH levels between 2.5 and 4.5 mIU/L21. This is at least one organization advocating a cut off of 2.5 mIU/L. If implemented, 20-26% would qualify for thyroid replacement22. I have seen more between 2.5 and 4.5 than below 2.5. Further, I have seen a benefit to treating this group.
Ask for your TSH, see where you fall.
Fork in the road
Based on everything above, if you get told your cholesterol numbers are bad, you can go one of two ways.
Support thyroid function, improve cholesterol metabolism and feel better.
Or.
Start on statins and risk side effects such as dementia and diabetes among others. Plus, many opportunities to lower cardiovascular risk exist outside of cholesterol-lowering drugs. Have a read of my paper Deprescribing Statins.
Not everyone experiences these side effects from statins, they aren’t on them long enough. Statins have a high discontinuation rate because people rarely felt good on them.
Thyroid replacement is not risk-free. However, most people normally feel better, especially with a T3 component. That T3 component also helps improve LDL-R expression.
As my data analysis shows, a vast majority of the people using thyroid replacement don’t take statins. Also, an overwhelming number of statin users are NOT using thyroid replacement. Connection? I think so.
If you pop “high” on a cholesterol test, ask for a thyroid panel as well. If the TSH comes back high, above 2.5, have a conversation with your doc about thyroid support. But before starting any prescriptions for thyroid, support thyroid health with tools from the improve section above, and see if your lab numbers approve (in collaboration with your doc). Please reach out if I can be of assistance.
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3109527/
- https://www.ncbi.nlm.nih.gov/pubmed/28987238
- https://www.ncbi.nlm.nih.gov/pubmed/22948212
- https://www.sciencedaily.com/releases/2011/07/110711131614.htm
- https://www.ncbi.nlm.nih.gov/pubmed/12414890
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3255175/
- https://www.ncbi.nlm.nih.gov/pubmed/16635908
- https://juniperpublishers.com/jojph/pdf/JOJPH.MS.ID.555563.pdf
- United States Patent 7,771,736
- https://www.sciencedirect.com/science/article/abs/pii/S0303720717300758
- https://www.ncbi.nlm.nih.gov/pubmed/25516464
- https://www.ncbi.nlm.nih.gov/pubmed/7593416
- https://www.ncbi.nlm.nih.gov/pubmed/6783498
- https://www.medscape.com/viewarticle/894601
- https://www.nahypothyroidism.org/deiodinases/
- https://www.westonaprice.org/health-topics/vegetarianism-and-plant-foods/living-with-phytic-acid/
- https://thyroidpharmacist.com/articles/selenium-deficiency-and-hashimotos/
- https://clincalc.com/DrugStats/Top200Drugs.aspx
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3743362/
- https://www.medpagetoday.com/meetingcoverage/esc/81919
- http://www.ncbi.nlm.nih.gov/pubmed/17991805
- https://academic.oup.com/jcem/article/98/9/3584/2833082
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