Bioidentical Hormones 101 
The Book, by Jeffrey Dach MD

Chapter 4. Why Natural Thyroid is Better than Synthroid, Part Two

thyroxine,synthroid,natural, thyroid,rlc lab,armour,forrest lab, osteoporosisChapter 4.  Why Natural Thyroid is

Better than Synthroid, Part Two

Will Thyroid Medication Give Me Osteoporosis ?

New concerns were raised by Dr. Marci Turner in the April 2011 British Medical Journal reporting elderly women on Synthroid(tm) have increased fracture risk.(13)  Note: Synthroid is a T4-only medication, also called thyroxine or levothyroxine.  A 2010 report by Murphy looked at thyroid function and fracture risk in normal postmenopausal women, and they found a 35% increase in fracture risk in women with lower TSH values (TSH=thyroid stimulating hormone). (1)  Higher TSH was protective of fracture.

Above left image : Thyroxine Chemical structure, courtesy of Wikimedia commons.

No Real Consensus on The Issue

To add confusion to the issue, a 2003 meta-analysis by Schneider reviewed 63 studies looking at the effect of thyroid medication (T4-only) on bone mineral density, finding no real consensus and concluding that, "currently debate still exists about the effects of thyroid hormone therapy on skeletal integrity, that is the safety of levothyroxine use with respect to bone mineral density." (14)(15)  Let us take a look at this issue and try to come up with some real answers.

The Calcitonin Connection

The thyroid gland not only makes thyroid hormone.  It also makes Calcitonin, a hormone manufactured by the parafollicular calls (C cells) in the thyroid tissue. (24)   Calcitonin is involved in calcium metabolism, bone maintenance and prevents osteoporosis.  

Thyroid Disorders Cause Destruction of Calcitonin Cells

Hashimoto's Thyroiditis is a common cause of hypothyroidism and is associated with destruction of the C-cells with loss of Calcitonin production. (2-4) The resulting Calcitonin deficiency is a potential cause of bone resorption and osteoporosis. (7-12) On the other hand, treatment with Calcitonin nasal spray is an FDA approved treatment for osteoporosis and is shown to increase bone density. (16) 

Hashimoto's, Radio-Iodine and Surgery all Destroy Calcitonin Cells

All three, the autoimmune process of Hashimoto’s Thyroiditis, Radioactive Iodine ablation and Thyroid surgical ablation, serve to reduce or eliminate thyroid function, and the C-cells which make Calcitonin get knocked out as well.  Synthroid, levothyroxine, and T4-only medications do not provide the missing Calcitonin.  One would expect the Calcitonin deficient patient to be at greater risk for osteoporosis and fracture.  Unlike Synthroid and T4-only medications which DO NOT contain Calcitonin, natural desiccated thyroid pills DO CONTAIN Calcitonin, providing the missing hormone, and is the preferred form of thyroid medication.  

Oral Absorption of Porcine Calcitonin

Since Calcitonin is a small peptide, it is subject to degradation and digestion when taken by the oral route.  To avoid the oral route, Porcine Calcitonin is given as intramuscular injection, and salmon Calcitonin which is 25 times more potent is given as intranasal spray.  Newer Calcitonin formulations use some type of carrier to allow for oral dosing.  Studies show that oral absorption of Calcitonin is a small fraction of the ingested dose, about 0.022%, yet even this small amount has a physiologic effect with a drop in serum calcium observed.(41)   How much Calcitonin is in a One Grain natural thyroid pill?  We don’t know the exact amount.  Obviously, further medical research in this area is needed.

None of the Studies Used Natural Desiccated Thyroid

Unfortunately, all of the medical studies of the bone density-thyroid connection used T4-only medication, none used desiccated natural thyroid, so we don't have any studies to evaluate the long term lack of osteoporosis from natural desiccated thyroid.  NIH funded research is needed to evaluate bone density and fracture risk for natural desiccated thyroid compared to T4-only medications.   Will this ever take place? Don't hold your breath.  The NIH is a government agency, and the government is influenced by Big Pharma dollars, so natural is out and synthetic is in.  We may never see NIH funding for research on natural desiccated thyroid.  

The TSH Connection, TSH is Protective and Prevents Bone Resorption

Advances in our understanding of physiology and animal research have revealed TSH hormone (thyroid stimulating hormone) has a direct effect on bone cells, preventing degradation of bone and bone resorption, and therefore protective of bone density.(17-19)  This could explain the many studies that find a correlation between higher TSH and improved bone density.  The problem with using TSH as a treatment for osteoporosis is that higher TSH is associated with increased heart disease (see the HUNT study), as well as a host of low thyroid symptoms of fatigue, malaise, muscle aches and pains etc.(25)  Patients feel better with a lower TSH and higher thyroid function, so cutting back on thyroid medication to let the TSH drift up may be good for bone density, but it is not good for the patient.

Good News About Bioidentical Hormones

The good news is that the TSH effect on bone density is relatively modest and is offset by the addition of estrogen, a bioidentical hormone, which increases bone density. (20)  In addition, we routinely employ a natural bone building program.  One of the interventions is to measure and optimize vitamin D levels which protects and maintains bone density.  In my experience with our TrueMedMD clinic patients using natural thyroid and bioidentical hormones, we have seen only benefits with increasing bone density, and no observed cases of osteoporosis. 

In conclusion, an excellent reason to switch from T4-only thyroid medication to natural desiccated thyroid is because it contains Calcitonin, protective of bone density and preventive of osteoporosis.  T4-only medication does not contain Calcitonin and is associated with loss of bone density and increased fracture risk.  We have found good clinical results with a natural desiccated thyroid product called Naturethroid from RLC labs. Dosage range is from one to four Grains per day depending on underlying thyroid function and body weight.  We pay close attention to clinical symptom resolution during the follow up period.  For lab monitoring, we follow the advice of Jonathan Wright MD who advocates the use of the serum Free T3 test, as more useful than the TSH test.


This is Part Two of a series, for Part One Click Here.


Articles with Related Interest:

Why Natural Thyroid is Better than Synthetic Part One
Why Natural Thyroid is Better than Synthetic Part Two
Why Natural Thyroid is Better than Synthetic Part Three



References  for Chapter 4, Why Natural Thyroid is Better than Synthetic Part Two

(1) http://www.ncbi.nlm.nih.gov/pubmed/20410228
J Clin Endocrinol Metab. 2010 Jul;95(7):3173-81. Epub 2010 Apr 21.
Thyroid function within the upper normal range is associated with reduced bone mineral density and an increased risk of nonvertebral fractures in healthy euthyroid postmenopausal women. Murphy E et al.

(2) http://www.ncbi.nlm.nih.gov/pubmed/9669288
Thyroid. 1998 Jun;8(6):505-9. Quantitative analysis of C cells in Hashimoto's thyroiditis.
Lima MA, Santos BM, Borges MF. Brazil.

(3) http://www.ncbi.nlm.nih.gov/pubmed/9797849
Calcitonin deficiency in early stages of chronic autoimmune thyroiditis
Borges MF, Abelin NM, Menezes FO, Dahia PL, Toledo SP. Department of Medicine, Federal School of Medicine of Triângulo Mineiro, Uberaba, Brazil.

(4) http://www.ncbi.nlm.nih.gov/pubmed/10646660
Thyroid. 1999 Dec;9(12):1211-4. Calcitonin reserve in different stages of atrophic autoimmune thyroiditis. Poppe K, Verbruggen LA, Velkeniers B, Finné E, Body JJ, Vanhaelst L.

(5)
http://www.ncbi.nlm.nih.gov/pubmed/11327616
Thyroid. 2001 Mar;11(3):249-55. One-year prophylactic treatment of euthyroid Hashimoto's thyroiditis patients with levothyroxine: is there a benefit? Padberg S et al.

(6) http://www.ncbi.nlm.nih.gov/pubmed/16006728
Endocr J. 2005 Jun;52(3):337-43.  Effects of prophylactic thyroid hormone replacement in euthyroid Hashimoto's thyroiditis.  Aksoy DY, Kerimoglu U, Okur H, Canpinar H, Karaagaoglu E, Yetgin S, Kansu E, Gedik O.  Source Section of Endocrinology and Metabolism, Department of Internal Medicine, Hacettepe University, Ankara, Turkey.

(7) http://endo.endojournals.org/cgi/content/full/147/9/4007
Endocrinology Vol. 147, No. 9 4007-4009
Calcitonin—Guardian of the Mammalian Skeleton or Is It Just a Fish Story? Scott Miller

(8) http://endo.endojournals.org/cgi/content/abstract/147/9/4010?ijkey=bd61473312d62e7a5ef50cedc6ef1baa19c21cf3&keytype2=tf_ipsecsha
Endocrinology Vol. 147, No. 9 4010-4021 Calcitonin Plays a Critical Role in Regulating Skeletal Mineral Metabolism during Lactation.  Janine P. Woodrow, Christopher J. Sharpe, Neva J. Fudge, Ana O. Hoff, Robert F. Gagel and Christopher S. Kovacs

(9) http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2680171/
J Bone Miner Res. 2008 August; 23(8): 1182–1193. Calcitonin Receptor Plays a Physiological Role to Protect Against Hypercalcemia in Mice.  Rachel A Davey et  al.

(10) http://www.ncbi.nlm.nih.gov/pubmed/10230474
Acta Med Austriaca. 1999;26(1):29-31. Possible effect of calcitonin deficiency on bone mass after subtotal thyroidectomy. Mirzaei S, Krotla G, Knoll P, Koriska K, Köhn H.

(11)
http://www.ncbi.nlm.nih.gov/pubmed/15258552 Minerva Endocrinol. 2004 Mar;29(1):1-10.
[Bone density and mineral metabolism in calcitonin-deficiency patients].  CONCLUSION: The results of this study show that the chronic lack of calcitonin in total thyroidectomized patients may play a role in increased bone degradation and osteopenia with a higher risk of bone fracture.

(12) http://www.ncbi.nlm.nih.gov/pubmed/1929193
Ann Endocrinol (Paris). 1991;52(2):109-12. [Chronic autoimmune thyroiditis and C-cell hyperplasia. Study of calcitonin secretion in 24 patients].[Article in French]Barbot N, Guyetant S, Beldent V, Akrass A, Cerf I, Perdrisot R, Bigorgne JC.

(13) http://www.bmj.com/content/342/bmj.d2238.full
BMJ 2011; 342:d2238 Levothyroxine dose and risk of fractures in older adults: nested case-control study.  Marci R Turner et al.

(14) http://www.ncbi.nlm.nih.gov/pubmed/14714266
Exp Clin Endocrinol Diabetes. 2003 Dec;111(8):455-70. The effect of levothyroxine therapy on bone mineral density: a systematic review of the literature.  Schneider R, Reiners C.

(15) http://thyroid.about.com/cs/osteoporosis/a/osteoporosis_2.htm
Is Thyroid Medication Going to Give You Osteoporosis? Experts Evaluate the Risks
What Does this Mean for Patients? Mary J. Shomon and Dr. William Cline March  2004

(16)
http://www.ncbi.nlm.nih.gov/pubmed/11874243
J Bone Miner Res. 2002 Mar;17(3):521-7. A randomized trial of nasal spray salmon calcitonin in men with idiopathic osteoporosis: effects on bone mineral density and bone markers. Trovas GP, Lyritis GP, Galanos A, Raptou P, Constantelou E.

 (17) http://www.ncbi.nlm.nih.gov/pubmed/20151763
Endocr Regul. 2010 Jan;44(1):9-15. The level of TSH appeared favourable in maintaining bone mineral density in postmenopausal women. Baqi L, Payer J, Killinger Z, Susienkova K, Jackuliak P, Cierny D, Langer P.

(18) http://www.ncbi.nlm.nih.gov/pubmed/15746993 J Bone Miner Res. 2005 Mar;20(3):480-6. Epub 2004 Nov 29. Recombinant human TSH modulates in vivo C-telopeptides of type-1 collagen and bone alkaline phosphatase, but not osteoprotegerin production in postmenopausal women monitored for differentiated thyroid carcinoma.
Mazziotti G, Sorvillo F, Piscopo M, Cioffi M, Pilla P, Biondi B, Iorio S, Giustina A, Amato G,

(19) http://www.ncbi.nlm.nih.gov/pubmed/19548061
J Bone Miner Metab. 2010;28(1):35-41. The effects of recombinant human TSH on bone turnover in patients after thyroidectomy. Karga H, Papaioannou G, Polymeris A, Papamichael K, Karpouza A, Samouilidou E, Papaioannou P.

(20) http://www.ncbi.nlm.nih.gov/pubmed/8563472 Thyroid. 1995 Oct;5(5):359-63.
Effect of estrogen replacement therapy upon bone mineral density in thyroxine-treated postmenopausal women with a past history of thyrotoxicosis.  Franklyn JA, Betteridge J, Holder R, Sheppard MC.

(21) http://www.ncbi.nlm.nih.gov/pubmed/2375563
Accelerated Bone Loss in Hypothyroid Patients Overtreated with L-Thyroxine
Annals of Internal Medicine August 15, 1990 vol. 113 no. 4 265-269  Glenn M. Stall, MD; Susan Harris, MS; Lori J. Sokoll, MCC; and Bess Dawson-Hughes, MD

(22)
http://www.ncbi.nlm.nih.gov/pubmed/14727010
Osteoporos Int. 2004 Mar;15(3):209-16. Epub 2004 Jan 16. Restoration of euthyroidism accelerates bone turnover in patients with subclinical hypothyroidism: a randomized controlled trial.

(23)
http://www.ncbi.nlm.nih.gov/pubmed/9156039
Clin Endocrinol (Oxf). 1997 Mar;46(3):301-7. Longitudinal changes of bone mineral density and bone turnover in postmenopausal women on thyroxine. Guo CY, Weetman AP, Eastell R.

(24) http://vet.sagepub.com/content/27/6/445.long
Veterinary Pathology November 1990 vol. 27 no. 6 445-452 Immunocytochemistry of Thyroid C-Cell Complexes in Dogs B. LEBLANCG, . PAULUSM, . ANDREUA, ND M. C. BONNET

(25) http://jeffreydach.com/2008/10/12/hunt-study-shows-thyroid-prevents-heart-attacks-by-jeffrey-dach-md.aspx Hunt Study Shows Thyroid Prevents Heart Attacks by Jeffrey Dach MD

(26) http://www.ncbi.nlm.nih.gov/pubmed/20429634
Endocr Regul. 2010 Apr;44(2):57-63. Thyrotropin versus thyroid hormone in regulating bone density and turnover in premenopausal women. Baqi L, Payer J, Killinger Z, Hruzikova P, Cierny D, Susienkova K, Langer P. 

(27) http://www.ncbi.nlm.nih.gov/pubmed/20688622
Hormones (Athens). 2010 Jul-Sep;9(3):245-52.  Combined therapy with L-thyroxine and L-triiodothyronine compared to L-thyroxine alone in the treatment of primary hypothyroidism.  Fadeyev VV, Morgunova TB, Melnichenko GA, Dedov II.

(28) http://www.ncbi.nlm.nih.gov/pubmed/11095447

J Clin Endocrinol Metab. 2000 Nov;85(11):4157-61.
Persistent increase in bone turnover in Graves' patients with subclinical hyperthyroidism.
Kumeda Y, Inaba M, Tahara H, Kurioka Y, Ishikawa T, Morii H, Nishizawa Y.

(29)
http://www.ncbi.nlm.nih.gov/pubmed/15278189
J Formos Med Assoc. 2004 Jun;103(6):442-7.  Bone mineral density in women receiving thyroxine suppressive therapy for differentiated thyroid carcinoma. Chen CH et al.

(30) http://www.ncbi.nlm.nih.gov/pubmed/16834835
Curr Med Res Opin. 2006 Jul;22(7):1369-73. Changes of bone mineral density in pre-menopausal women with differentiated thyroid cancer receiving L-thyroxine suppressive therapy. Mazokopakis EE, Starakis IK, Papadomanolaki MG, Batistakis AG, Papadakis JA.

(31)
http://www.ncbi.nlm.nih.gov/pubmed/12803168
Ann Intern Med. 2001 Apr 3;134(7):561-8. Risk for fracture in women with low serum levels of thyroid-stimulating hormone. Bauer DC, Ettinger B, Nevitt MC, Stone KL

(32) http://www.ncbi.nlm.nih.gov/pubmed/19892039?dopt=Abstract
Bone. 2010 Mar;46(3):747-51. Epub 2009 Nov 3.
Serum TSH values and risk of vertebral fractures in euthyroid post-menopausal women with low bone mineral density. Mazziotti G, Porcelli T, Patelli I, Vescovi PP, Giustina A.
SourceDepartment of Medical and Surgical Sciences, University of Brescia, Italy.

(33) http://www.ncbi.nlm.nih.gov/pubmed/7891045?dopt=Abstract
J Intern Med. 1995 Mar;237(3):241-7. Hip fractures and the thyroid: a case-control study. Wejda B, Hintze G, Katschinski B, Olbricht T, Benker G.

(34)
http://www.ncbi.nlm.nih.gov/pubmed/9579237
Clin Endocrinol (Oxf). 1998 Feb;48(2):229-34. Effect of replacement doses of thyroxine on bone mineral density. Hanna FW, Pettit RJ, Ammari F, Evans WD, Sandeman D, Lazarus JH.

(35) http://www.ncbi.nlm.nih.gov/pubmed/15555712
J Affect Disord. 2004 Dec;83(2-3):183-90. Bone mineral density during maintenance treatment with supraphysiological doses of levothyroxine in affective disorders: a longitudinal study.
Bauer M et al.

(36) http://www.ncbi.nlm.nih.gov/pubmed/11578671
J Affect Disord. 2001 Oct;66(2-3):185-91. Bone mineral density in pre-and post-menopausal women with affective disorder treated with long-term L-thyroxine augmentation. Gyulai L, Bauer M et al.

(37) http://www.ncbi.nlm.nih.gov/pubmed/14748891
J Clin Pharm Ther. 2004 Feb;29(1):1-5.  Effects of levothyroxine suppressive therapy on bone mineral density in premenopausal women. Larijani B, Gharibdoost F, Pajouhi M, Sadjadi A, Aghakhani S, Eshraghian R, Akrami SM, Maalouf G.

(38)
http://www.ncbi.nlm.nih.gov/pubmed/7647577
Thyroid. 1995 Apr;5(2):81-7. Possible limited bone loss with suppressive thyroxine therapy is unlikely to have clinical relevance. Müller CG, Bayley TA, Harrison JE, Tsang R.

(39)
http://www.ncbi.nlm.nih.gov/pubmed/16322336
Endocr Relat Cancer. 2005 Dec;12(4):973-81. Lack of deleterious effect on bone mineral density of long-term thyroxine suppressive therapy for differentiated thyroid carcinoma. Reverter JL, Holgado S, Alonso N, Salinas I, Granada ML,

(40)
http://www.ncbi.nlm.nih.gov/pubmed/11698925
Medscape Womens Health. 2001 Oct;6(5):3. Bone loss in premenopausal women on long-term suppressive therapy with thyroid hormone. Sijanovic S, Karner I.

(41) http://www.ncbi.nlm.nih.gov/pubmed/8587058  Utility of pharmacodynamic measures for assessing the oral bioavailability of peptides. 1. Administration of recombinant salmon calcitonin in rats. Patrick J. Sinko1 et al. J Pharm Sci. 1995 Nov;84(11):1374-8.  The absorption of rsCT after id. (Duodenal)administration was low (0.022%); however, a significant lowering of serum calcium concentrations was observed.

author: Jeffrey Dach MD  Dr Dach


Website Builder