The Advantages of Whole Thyroid
Slowing Age-Related Thyroid Decline
By Gail Valentine, D.O.
hen supplementing an underactive thyroid gland, it is almost always better to use a whole thyroid extract rather than just a single thyroid hormone, e.g., thyroid hormone. This is because most endocrine glands throughout the body have been found to age similarly or at nearly the same rate. Automobiles as a whole are much more dissimilar in the way they age: a tire may have to be replaced every 15 or 20 thousand miles, while a piston may last for the life of the car, 80 to 100,000 miles. Yet we can't replace body parts so easily - at least not yet. So we must think of them with less indifference and with more respect. Just as we would measure the performance level of a tire with a pressure gauge, we usually follow the status of the thyroid by measuring a particular hormone known as thyroid stimulating hormone (TSH). TSH alone is often used as the gauge to determine whether supplementation is needed in clinical practice. The relationship between thyroid levels and TSH levels is inverse, which is to say that as thyroid hormones levels rise in the body, TSH levels normally fall.
In conventional medicine, it is usual practice to monitor levels of TSH to make sure these levels don't fall too low. Should this occur, the practice is to reduce the quantity of thyroid given as a supplement. Considerable attention should also be given to high-normal or low-normal TSH levels, but other factors are often taken into consideration before making final recommendations. The premise is that because thyroid function changes with age, it is helpful to monitor TSH levels periodically to insure that the quantity of thyroid supplement being taken maintains appropriately youthful levels. If an individual is not taking a thyroid supplement, the TSH, along with other clinical indicators, can indicate whether it may be useful.
Like any other laboratory test, TSH has a "normal" range. Many conventionally minded physicians believe that "anywhere within the normal range" is okay. Other physicians believe that laboratory tests along with other clinical indicators can be a better reflection of thyroid function.
Another major controversy in the treatment of age-related thyroid decline or thyroid underactivity concerns the use of natural glandular concentrates or extracts containing thyroid hormones (e.g., Armour Desiccated Thyroid, Nathroid, Westhroid, and other brands derived from the thyroid gland of the pig) versus synthetic (laboratory-made) thyroid hormone (e.g., Levothroid, levothyroxin, and others). Not surprisingly, most conventional physicians prefer the synthetic product, which is widely promoted by pharmaceutical companies. (Synthroid is the third leading drug sold in the U.S.) Whether it is superior is open to serious question, however.
When supplementing an underactive thyroid
gland, it is almost always better to use
a whole thyroid extract rather
than just a single thyroid hormone.
Armour Thyroid and other natural thyroid preparations contain natural thyroid hormones. Although these preparations have been criticized by some for being "impure" or "inconsistent" from dose to dose, it should be noted that Armour Thyroid and most natural thyroid preparations are made to standards approved by the United States Pharmacopeia (USP), which helps to assure that its potency is accurate as stated on the label.
Natural thyroid preparations contain T4, T3, T2, and T1 and most closely resemble natural human thyroid hormones. In fact, the glandular extracts from animal thyroid glands are identical to human hormones. Unlike the differing molecular structure of the horse estrogen "equilin" and natural horse estrogens (used in Premarin for estrogen replacement therapy in women), the molecular structure of animal T4, T3, T2, and T1 is precisely the same as that of human thyroid hormones. At the proper dose, natural thyroid hormones work quite well.
Synthetics, on the other hand, consist solely of T4. They depend on the body to convert the T4 to T3 and other metabolites. This may be fine for some people, but, for those whose thyroid underfunction is caused not by a reduction in T4 production, but by a defect in the conversion of T4 to T3, giving T4 may not help much.
Natural thyroid preparations contain
T4, T3, T2, and T1 and most closely resemble
natural human thyroid hormones. In fact, the
glandular extracts from animal thyroid glands
are identical to human hormones. Synthetics,
on the other hand, consist solely of T4.
The natural versus synthetic hormone debate has raged since the early part of the 20th century, when large drug companies first learned to make synthetic hormones, or molecules very similar to human hormones. It's actually only a part of the larger and almost forgotten debate in endocrinology (also called "organotherapy" in the early 20th century). The larger debate was over the use of "uniglandular" versus "pluriglandular" formulations in endocrine therapy. Not surprisingly, those in favor of the "uniglandular" approach tended to be physicians more dependent and reliant on laboratory evaluation, while proponents of "pluriglandular" therapy tended to be more reliant on clinical observations.
Henry R. Harrower, M.D., a pioneering endocrinologist/organotherapist during the first half of the 20th century, was a leading advocate of the "pluriglandular" approach. According to Harrower, "clinical experience has established this beyond all doubt - literally thousands of cases of dyscrinism [a now rarely used term for any endocrine malfunction] having been treated with single endocrine products without satisfactory results have, on changing to an indicated pluriglandular remedy, shown results so different that they are remarkable."1 In a later publication, Harrower wrote, "Because the family of glands is closely interrelated, it is difficult to hurt one member without injuring others."2 He went on to quote the editor of the medical journal The Prescriber: "Pluriglandular therapy while still practiced with considerable success is undergoing a change. It is as unjustifiable to condemn it wholesale as it is to practice it blindly. More than one eminent endocrinologist has recently admitted that certain glandular preparations often act better when combined with thyroid."3 In his 1922 work, Harrower also wrote: "The facts warrant the combination of synergistic gland extracts no matter whether we can see clear clinical evidence of disorder of these synergistic glands. It must be remembered that symptoms do not necessarily manifest themselves for quite some time after the beginning of actual dysfunction in the cells."4
Even at the level of 1/4 grain of a
natural thyroid component,
according to Wright,
people widely comment that
their energy levels are higher, their
thinking is clearer, and their bowel
function is better.
The pluriglandular option is likely the best of all for those who wish to prevent age-related decline. Jonathan Wright, MD, a well known nutritional physician, feels that one should consider a newly developed glandular formulation as a part of one's anti-aging program. As Dr. Wright says, "It's of course very likely that as we age, all endocrine glands except the ovaries age at about the same rate. So it makes no sense to single out one or another endocrine gland as part of the general anti-aging program. Especially in anti-aging, it's best to return to Harrower's approach and use them all."
The data, both clinical and experimental, strongly support the idea that a small daily serving of whole thyroid extract as a dietary supplement can have a wide range of positive influences. Dr. James Isaacs, a pioneering cardiovascular surgeon from Baltimore, conducted a classic study in 1974 and found that those who took 1/4 grain of thyroid combined with minerals and vitamins over a period of 10 years showed significant improvement in cardiovascular-protective function.5
If you're over 40 years of age and have no overt endocrine disease, and you wish to slow the aging process, then Dr. Wright feels supplementation is an option to consider. He points out that even if one is not experiencing symptoms, all endocrine glands are beginning to slow down at this stage of life. Even at the level of 1/4 grain of a natural thyroid component, according to Wright, people widely comment that their energy levels are higher, their thinking is clearer, and their bowel function is better.
And what if you're taking thyroid supplementation already? Most people can still get added benefit from other hormonal extracts, says Dr. Wright. He concludes, "While there are a few individuals who are very sensitive to thyroid supplementation and must have exactly the right amount, you might consider an additional supplement because, even if it adds only 1/4 grain of the actual thyroid itself, the other hormonal extracts influence the endocrine network as a whole."
- Harrower HR. Practical organotherapy: the internal secretions in general practice. The Harrower Laboratory, Glendale CA; 1922, p34.
- Harrower HR. An endocrine handbook. The Harrower Laboratory, Glendale CA; 1939, p9.
- Harrower HR. 1939 ibid.
- Harrower HR. 1922 ibid.
- Isaacs JP, Lamb JC. Trace metals, vitamins, and hormones in ten-year treatment of coronary atherosclerosis and heart disease. Delivered at the Texas Heart Institute Symposium on Coronary Medicine and Surgery, Houston, Texas, on February 21, 1974. LC Call No: RC6685.C6.I588.