A recent thread reminded me about the great work Dr. Lowe had done and I got to Googling.

I was reading on the site for which he was editor-in-chief (ThyroidScience.com) and stumbled upon the letters to the editor section.

Lo and behold, Dr. Lowe provides scientific explanation about the benefits of T3 in regards to weight loss.

He also explains how cholesterol levels can increase in hypothyroid people.....and how thyroid hormone is really the only treatment a person with high cholesterol levels really needs.

Here it is with medical references at the bottom":


Subject: Thanks to you!
From: Jacqueline Herrera
Date: Mon, December 8, 2008 9:32 pm
To: editor@thyroidscience.com

Dear Dr. Lowe: I'm so thankful I was told about ThyroidScience.com. I read the article on "Weight Gain and the TSH" and sent it to my three sisters who also suffer from hypothyroidism. I started the Armour Thyroid medication almost two weeks ago and feel so much better than the last 7 years of being on levothyroxine. I know this is a positive start in the right direction for me personally. I have 30 pounds to get rid of that I've gained in the last 7 years after two consecutive pregnancies in 2002 and 2003. Thank you for making this information available to the people (not just doctors) who are pro active about their health.

Jacqueline Herrera
Phoenix, Arizona

Editors Reply (December 25, 2008)

Dear Jacqueline: Thanks so much for writing about feeling better on Armour Thyroid after gaining thirty pounds of weight while on levothyroxine. If you use a high enough dosage of Armour, I expect that youll lose the 30 lbs you gained over the seven years that you used levothyroxine. This is especially likely if you have a wholesome diet and regularly exercise to tolerance.

Armour Thyroid, like Nature-Throid and Westhroid, is more effective than levothyroxine at reducing body fat. The reason is that these products contain T3. Some researchers say that T3 has a lipolyticthat is, a fat-decomposingaction in fat cells.[3] One way T3 reduces fat in the cells is by inhibiting an enzyme (cyclic-AMP phosphodiesterase) that slows down metabolism shortly after adrenaline and noradrenaline speeds it up.[1][3][8] By blocking this enzyme, T3 sustains the fat-decomposing effect of adrenaline and noradrenaline in fat cells.[1][2][8] Another way T3 reduces fat is by altering gene transcription for several compounds. When T3, acting through the relevant genes, increases fat cells production of these compounds, the compounds augment adrenalines and noradrenalines fat-lowering effect in the cells.[10]

In addition to weight loss, you may get another benefit from the T3 in Armour: that is, a reduction of fat that probably accumulated in your arteries[3] while you were on T4 replacement. As Duntas wrote,[11] As Duntas noted in 2002, the composition and transport of blood fats are seriously disturbed in thyroid diseases. Among patients with an high TSH and low thyroid hormone levels, cholesterol and LDL are typically high. Even when thyroid hormone levels are within the reference range but the TSH is high, patients on average have a slightly high total cholesterol, high LDL, and low HDL. These patients also have abnormalities of the linings of arteries, inflammation and fat accumulation in the aorta, and they are subject to have myocardial infarctions. They also have increased resistance to blood flow, weaker contractions of the heart muscle, and increase diastolic blood pressure. As Duntas pointed out, thyroid hormone therapyespecially with TSH-suppressive dosagesusually leads to a considerable improvement in the lipid profile.

T3 reduces fat in artery linings in part by increasing the activity of an enzyme called lipoprotein lipase.[4] Low activity of this enzyme leads to high blood fats, which is a risk factor for coronary heart disease.[7] Thyroid hormone increases the activity of the enzyme, and by doing so, it reduces blood fats.[4] Thyroid hormone also lowers LDL cholesterol by increasing the number of LDL receptors on liver cells.[11]

In my clinical experience, thyroid hormone therapy (with products that contain T3) is by far more effective than statin drugs in normalizing blood fats. I believe that if patients in general were allowed to use effective thyroid hormone therapy rather than T4 replacement, we could virtually eliminate the market for statin drugs. Then patients would be free from the potential adverse effects of statin drugs, such as chronic muscle pain and other pain syndromes, elevated liver enzymes, peripheral neuropathy, and muscle damage.[9]

Please let us know how you progress. I wish you the best for losing the weight you gained while on levothyroxine.

References

1. Bgin-Heick, N. and Heick, H.M.: Increased response of adipose tissue of the ob/ob mouse to the action of adrenaline after treatment with thyroxin. Can. J. Physiol. Pharmacol., 55(6):1320-1329, 1977.

2. Elks, M.L. and Manganiello, V.C.: Effects of thyroid hormone on regulation of lipolysis and adenosine 3',5'-monophosphate metabolism in 3T3-L1 adipocytes. Endocrinology, 117(3):947-953, 1985.

3. Mandel, L.R. and Kuehl, F.A., Jr.: Lipolytic action of 3,3'5-triiodo-L-thyronine, a cyclic AMP phosphodiesterase inhibitor. Biochem. Biophys. Res. Commun., 28(1):13-18, 1967.

4. Pyklist, O., Goldberg, A.P., and Brunzell, J.D.: Reversal of decreased human adipose tissue lipoprotein lipase and hypertriglyceridemia after treatment of hypothyroidism. J. Clin. Endocrinol. Metab., 43(3):591-600, 1976.

5. Beisiegel, U.: Lipoprotein metabolism. Eur. Heart J., 19 Suppl A:A20-A23, 1998.

6. Otto, W., Taylor, T.G., and York, D.A.: Glycerol release in vitro from adipose tissue of obese (ob/ob) mice treated with thyroid hormones. J. Endocrinol., 71(1):143-155, 1976.

7. Salter, A.M. and Brindley, D.N.: The biochemistry of lipoproteins. J. Inherit. Metab. Dis., 11 Suppl 1:4-17, 1988.

8. Wahrenberg, H., Wennlund, A., and Arner P.: Adrenergic regulation of lipolysis in fat cells from hyperthyroid and hypothyroid patients. J. Clin. Endocrinol. Metab., 78(4):898-903, 1994.

9. Brown, W.V.: Safety of statins. Curr. Opin. Lipidol., 19(6):558-562. 2008.

10. Viguerie, N., Millet, L., Avizou, S., et al.: Regulation of human adipocyte gene expression by thyroid hormone. J. Clin. Endocrinol. Metab., 2002 Feb;87(2):630-634, 2002.

11. Duntas, L.H.: Thyroid disease and lipids. Thyroid, 12(4):287-293, 2002.