Ian Spohn, ND, is a staff naturopathic doctor for Energique who enjoys challenging the dogmas of both conventional and alternative medicine. He is a passionate supporter of the paleo diet and classical homeopathy.
With advances in science and medicine allowing more people to live longer, maintaining health and function into old age will become more important than ever. Faced with an aging population, treatment approaches are needed to support a healthful aging process, and this will require a better understanding of how the aging process unfolds. Questions as to what extent aging is inevitable and speculation as to the true upper limits of the human life span continue to inspire research in the field of antiaging medicine. While the telomere and free radical theories of aging have been thoroughly explored, it may be that the thymus gland actually holds the keys to life and death.
It is believed that the thymus gland is named for the Greek word thumos, meaning spirit. More specifically, the word thumos refers to a certain emotion which might be called righteous anger, the sensation of one’s spirit rising up to defend one’s wounded honor. When such an emotion is extrapolated into mundane physiological terms, it makes sense that the thymus is considered the master gland of the immune system. Essentially a specialized lymph node, it is also a part of the endocrine system because it secretes a hormone called thymalin, the effects of which are just beginning to be understood. The main function of the thymus gland is to regulate the adaptive immune system and, especially, to maintain self-tolerance. The body’s adaptive immune system is designed in such a way that it can make specialized immune cells to fight literally any possible antigen. It does this by randomly recombining a critical section of each naïve T-cell’s genes each time they’re reproduced, like shuffling a deck of cards. The possible combinations are nearly endless, which provides the body the incredible ability to produce immune cells specifically designed to destroy virtually any pathogen.
The randomness of this process ensures that no matter what type of pathogen the body encounters, eventually it will produce (and subsequently clone) the perfect lymphocyte to defend itself. This comes with a serious potential downside, however. Since the process is random and literally any combination is possible, it is inevitable that sometimes this random generation will produce immune cells equipped to recognize and destroy the body through its own antigens. The thymus gland is the solution to this. Every new T-cell must pass through the thymus before becoming activated. The thymus keeps a sort of record of all the self antigens which are to be found throughout the body and tests each new T-cell to see if it reacts to any of them. If there is any threat of an autoimmune reaction, that T-cell with its unique antigen receptor is destroyed. A healthy thymus is therefore essential to preventing autoimmunity.
If the thymus were to become less functional with time, it would have two consequences. First, the rate of overall T-cell activation would decline, greatly weakening the versatility of the adaptive immune system. Two, self-tolerance would start to break down, leading to an increased risk of progressive, immune-mediated tissue damage if not outright autoimmune disease. Thus, many of the most common chronic diseases and eventual causes of death, with a few exceptions (such as accidents, the effects of a poor diet, toxic exposures, etc.), could theoretically be explained by a reduction in thymus activity. Even cancer, when not due to an obvious carcinogenic exposure, could be explained as failed immune surveillance and tumor suppression by the adaptive immune system. With the exception of fatal accidents and lifestyle diseases, almost every cause of death – be it cancer, infection, autoimmune disease, or progressive loss of function due to accumulated tissue damage – could theoretically be blamed on an underactive thymus, and, in fact, this process of immunosenescence has already been implicated in our failure to increase the maximum life expectancy, despite numerous advances that have allowed more people to reach it (Aw et al., 2007).
In support of this possibility, and what has really aroused the interest of anti-aging researchers, is the remarkable fact that the thymus gland progressively involutes with age. Not only that, but when this rate of involution is projected to its theoretical endpoint, it correlates very closely with the observed upper limit of the human life span, somewhere in the neighborhood of 120 years (Csaba, 2016). The thymus is at its largest during childhood, when the immune system is entirely naïve and the ability to quickly acquire adaptive immunity is most important. After puberty, for reasons that are still unclear, the thymus begins to shrink. It is believed that this is mediated by sex hormones, but it continues relentlessly through adulthood even in castrated individuals (Rezanni et al., 2014). After puberty, the thymus continues to shrink at a rate of about three percent per year until around age 50, at which point it continues to shrink about one percent per year. By age 70, on average less than 10 percent of the original thymus gland remains active (Lynch et al., 2009). This means that even if you are lucky enough to avoid death by tragic circumstances and even if you have a perfectly healthy lifestyle, whether you like it or not, it is only a matter of time before your thymus and, with it, your adaptive immune system disappears, leaving you utterly defenseless against any freshly mutated strain of epidemic disease you come across. And vaccination won’t save you, as the body cannot respond to vaccines in the first place without an adaptive immune system.
The correlates between a shrinking thymus and eventual death are quite numerous. It is noteworthy that the thymus shrinks slightly faster in the presence of testosterone than it does in the presence of estrogen (Rezzani et al., 2014), which might explain why women seem to live slightly longer than men on average. Also it seems to shrink faster in response to high blood sugar (Ibid.), which might explain why laboratory animals live longer when kept on calorie-restricted diets (Barger et al., 2003). The most startling evidence comes from studies comparing the rate of thymic involution across different dog breeds, which reveals a direct correlation between the average life span of the breed and its rate of thymic involution. Basically, long-lived breeds have a slower rate of thymic involution than do short-lived breeds (Holder et al., 2016), implying a direct link between the thymus gland and aging. All this has led researchers to speculate that the thymus gland is essentially a pacemaker for the life span (Csaba, 2016); in essence, a sand-filled hourglass which, once depleted, results in catastrophic immune system failure and inevitable death through the agency of pathogens which constantly surround us.
But what about telomeres? Weren’t they supposed to be the key to preventing aging? While the field of anti-aging medicine was initially very excited about telomeres, there are actually several problems with the telomere theory of aging. It’s indisputable that telomeres do play some role in the aging process. Knocking out the telomerase enzyme in rats causes them to die sooner, proving that accelerated telomere loss can hasten one’s demise. However, meta-analyses disappointingly have shown that the association between telomere length and life span decreases markedly with advancing age (Boonekamp et al., 2013). In other words, the older you are, the less your remaining telomere length has anything to do with your remaining life span. This suggests that while losing telomeres too early can kill you, preserving or restoring them alone will not be enough to save you, implying there must be another factor behind the aging process. There is also the problem of the wide variation in telomere length across different species, which, unlike the rate of thymus involution in dogs, has no correlation whatsoever with each species’ life span (Gomes et al., 2011). Lab rats, for instance, have telomeres ten times longer than those of humans (Ibid.)! Across species, smaller body size, not longer life span, seems to correlate with longer telomeres, and being a warm-blooded species is associated with shorter telomeres. Because telomeres limit a cell’s number of viable reproductions, short telomeres may actually be a tumor-suppressive adaptation. Each time a cell divides it accumulates more DNA errors, so putting a limit on a cell’s reproductive life span might actually help prevent long-lived creatures from getting cancer. The rate of DNA replication errors is much higher in warm-blooded animals (Ibid.), which might explain why they have shorter telomeres. Whatever the case, the loss of telomeres alone does not explain normal death and aging.
If, as seems likely, much of aging can be explained through thymic involution, it opens new possibilities on the frontiers of anti-aging medicine. It is not known why the thymus relentlessly degenerates, though obesity seems to shrink it faster (Yang et al., 2009), as does free radical oxidation in general (Chaudhry 2016). Zinc deficiency can also cripple the thymus gland, as zinc is required for its main hormone thymalin. Zinc supplementation has actually been shown to reverse thymic atrophy in previously malnourished children (Golden et al., 1977). Maintaining a healthy weight and blood sugar level and ensuring adequate intake of zinc and a variety of antioxidants would seem to be simple and sensible steps to help protect the thymus gland and prolong one’s life at least to its natural limit. Many herbs have also been shown to protect the thymus gland, especially adaptogen herbs such as Eleutherococcus. When rats were forced to repeatedly swim to exhaustion as a model of chronic stress, Eleutherococcus reduced stress-induced atrophy of the thymus gland (Brekhman & Dardymov, 1969).
Yet another intriguing strategy is to take animal-derived thymus concentrates or extracts to support the thymus gland. Formerly known as sweetbreads (along with the pancreas), the thymus glands of calves were once highly prized as food. Today, a more common approach is glandular therapy using whole-thymus extracts, a form of nutritional supplementation intended to provide through its consumption all of the raw materials needed to heal and maintain a healthy thymus gland. Thymus extracts are recommended to support all aspects of the immune system, and preliminary research suggests they may hold promise for treating allergies, chronic viral infections, autoimmune disease, and even death itself. In a groundbreaking research study conducted in Russia, supplementing the hormones thymalin and epithalamin (secreted respectively by the thymus gland and the pineal gland, to help regulate the thymus) to elderly people not only reduced their rate of respiratory infections over a period of several years, but even prolonged their life span when compared to a control group (Khavinson & Morozov, 2003). In many mystical traditions, the pineal gland was considered the seat of the soul, and it has been shown that the pineal and thymus glands are linked. Removing the pineal gland from neonatal rats results in rapid involution of the thymus and early death (Csaba, 2016).
The thymus gland is one of the most popular raw tissue concentrates. Glandular concentrates are considered to be superior to glandular extracts, the difference being that concentrates contain the entire gland whereas the process of producing extracts from the gland results in the loss of many vital nutrients. Energique’s raw tissue concentrates are produced through a process called lyophilization, which essentially freeze-dries the tissue to concentrate and preserve it in a form that can be taken as a supplement. Energique’s Intact Multigland is an excellent nutritional supplement to support the thymus, and our Immunique™ capsules are enriched with thymus concentrate in addition to immune-supporting vitamins and minerals.
References
Aw et al., 2007 - Aw D, Silva AB, Palmer DB. Immunosenescence: emerging challenges for an ageing population. Immunology. 2007;120(4):435-46.
Csaba, 2016 - Csaba, Gyorgy. The Immunoendocrine Thymus as a Pacemaker of the Lifespan. Acta Microbiologica et Immunologica Hungarica. 2016;63(2):139-58.
Rezzani et al., 2014 - Rezzani R, Nardo L, Favero G, Peroni M, Rodella LF. Thymus and aging: morphological, radiological, and functional overview. Age (Dordr). 2014;36(1):313-51.
Lynch et al., 2009 - Lynch HE, Goldberg GL, Chidgey A, Van den Brink MR, Boyd R, Sempowski GD. Thymic involution and immune reconstitution. Trends Immunol. 2009;30(7):366-73.
Barger et al., 2003 - Barger JL, Walford RL, Weindruch R. The Retardation of Aging by Caloric Restriction: Its Significance in the Transgenic Era. Exp Gerontol. 2003 Nov-Dec;38(11-12):1343-51.
Holder et al., 2016 - Holder A, Mella S, Palmer DB, Aspinall R, Catchpole B (2016) An Age-Associated Decline in Thymic Output Differs in Dog Breeds According to Their Longevity. PLoS ONE 11(11): e0165968. https://doi.org/10.1371/journal.pone.0165968
Boonekamp et al., 2013 - Boonekamp JJ, Simons M, Hemerik L, Verhulst S. Telomere Length Behaves as Biomarker of Somatic Redundancy rather than Biological Age. Aging Cell. 2013;12(2):330-332.
Gomes et al., 2011 - Gomes NM, Ryder OA, Houck ML, et al. Comparative biology of mammalian telomeres: hypotheses on ancestral states and the roles of telomeres in longevity determination. Aging Cell. 2011;10(5):761-8.
Yang et al., 2009 - Yang H, Youm YH, Vandanmagsar B, et al. Obesity accelerates thymic aging. Blood. 2009;114(18):3803-12.
Chaudhry et al., 2016 - Chaudhry MS, Velardi E, Dudakov JA, van den Brink MR. Thymus: the next (re)generation. Immunol Rev. 2016;271(1):56-71.
Golden et al., 1977 - Golden MH, Jackson AA, Golden BE. Effect of Zinc on Thymus of Recently Malnourished Children. Lancet. 1977 Nov 19;2(8047):1057-9.
Brekhman & Dardymov, 1969 - Brekhman II, Dardymov IV. Ann Rev Pharmacol 1969;9:419-430.
Khavinson & Mozorov, 2003 – Khavinson VKh, Morozov VG. Peptides of Pineal Gland and Thymus Prolong Human Life. Neuro Endocrinol Lett. 2003 Jun-Aug;24(3-4):233-40.
Any homeopathic claims are based on traditional homeopathic practice, not accepted medical evidence. Not FDA evaluated.
These statements have not been evaluated by the Food and Drug Administration. These products are not intended to diagnose, treat, cure, or prevent any disease.