What a great conference! I had heard such high praise for the inaugural meeting of the Ancestral Health Symposium last August, but I was too late to register in 2011. This year I submitted an abstract that was accepted as a poster presentation. For those who missed it, I’ve attached a copy of my presentation below.
What an edifying and uplifting experience! We just wrapped up three days of excellent talks, panels, poster presentations and plenty of informal networking and socializing. This conference is really the hub of the Paleo movement. The emphasis was on the most recent developments in the scientific, cultural, political, and practical approaches to overcoming the contemporary health epidemics that derive from a mismatch between contemporary lifestyles and the biology of our evolutionary heritage. The talks and panels were diverse, covering nutrition, cholesterol, cancer, immune health, farming, exercise, and many other topics.
My previous post of July 15 contains links to the webpage of the Ancestral Health Symposium, where you can read about its purpose and review the program of speakers and other presenters. The conference certainly did not disappoint.
The program was composed of formal podium presentations, panel discussion and poster presentations. There were formal poster presentation sessions right after lunch on Friday and Saturday, where the poster presenters stood by their posters, provided a short overview, and then engaged in extensive Q&A. I liked this format very much because it maximized interaction and allowed me to meet many long time followers and newly interested people. I was also able to continue discussions next to the poster throughout the day at various times.
Many of you who could not attend may be interested in learning more about my presentation and how it was received.
My talk was a very high level summary of what I’ve written about on this blog over the past two years. It very well received and I was overwhelmed by the level of interest in hormesis. My presentation started with a general overview of hormesis and a number of practical examples of how to apply it. Since it would have been impossible to cover every application, I selected three to focus on:
- Calorie restriction and intermittent fasting
- Allergen immunotherapy
- Vision improvement
While there was interest in all of these topics, one topic in particular generated the greatest interest. Can you guess which one?
This was an audience that was on the whole unusually physically fit, and there was intense interest in looking to the wisdom embodied in human evolution and pre-industrial and pre-agricultural society as a source of ideas for improved health. Yet a significant number of attendees were wearing glasses — not exactly a “paleo” practice. So there was acknowlegement when I pointed out that myopia is not in our genes, but has become prevalent because of environmental factors — primarily intensive schooling, near work and poor visual habits. (Many thanks to Otis Brown for the analysis and reference to the Eskimo study I referenced in support of this point). Yet there was shock — and intense interest — when I pointed out that myopia can be prevented and even reversed by the techniques I discuss in my blog. Several of you discussed this with me and expressed a desired to embark upon a program to reverse myopia, and in some cases hyperopia or presbyopia.
I’m attaching here a link to a pdf copy of the poster. Keep in mind that the actual poster size was 48″ wide by 36″ tall, so it does not fit on a normal computer screen. But you can easily adjust the zoom and use the arrows on your keyboard to scroll around, or print it out in a reduced size format if you have good eyesight:
For those who have trouble reading the poster, or want an easier read, I present below the full text and set of images in the form of a standard blog article. Most of the content will be familiar to those of you who have read this blog over the past few years. But for those of you who are new to the topic of hormesis, I think it provides a good overview. I’ve also hyperlinked to articles on a number of the topics that are discussed, for further reading.
HORMESIS: A NEW LENS FOR UNDERSTANDING HEALTH AND IMPROVING RESILIENCE
Overstressed – or understressed? What explains the recent pandemic rise in “diseases of civilization” like obesity, diabetes, cardiovascular disease, autoimmunity and cancer – conditions much less prevalent in ancestral populations?
One common answer is that contemporary life is too stressful. The prescription is to minimize exposure to certain chemicals, foods, UV, or psychological stress. But stress is a double-edged sword. While chronic or excessive levels of stress can indeed cause illness, so can a “deficiency” of stress. Exposure to stress at the right intensity and frequency activates the body’s natural defense and repair mechanisms, improving health and resilience. The hardier life of our ancestors had benefits.
This poster presents the case for judicious application of progressive, intermittent stress to overcome conditions as diverse as obesity, addiction, depression, allergies and even myopia.
What is hormesis? Hormesis is a biological phenomenon whereby a beneficial effect (improved health, stress tolerance, growth or longevity) results from exposure to low doses of an agent that is toxic or lethal at higher doses.
The LNT (linear no-threshold) model of conventional toxicology assumes that toxic effects are inhibitory even at very low doses. But many examples have been found of “hormetic” chemicals or stimuli with a “biphasic” or “inverted U” dose response curve, illustrated below. At low doses, the “toxic” or inhibitory agent actually becomes stimulatory or beneficial to the organism. 
Hormesis appears to work by activating endogenous defense and repair mechanisms found in all organisms, thereby improving resistance to stress and disease.
Examples of Hormesis
MECHANISMS AND APPLICATIONS OF HORMESIS
Diets with calories reduced by 30-65% versus free feeding have been shown to extend lifetime and reduce degenerative disease in a wide variety of animals. . What explains this? Several proposed mechanisms have been demonstrated:
Autophagy: A cellular “recycling” process. Calorie restriction dramatically lowers the concentrations of insulin, IGF-1 and growth hormone, activating enzymes that degrade damaged intracellular macromolecules and use them for energy.
Mitohormesis: A defense response initiated in the mitochondria. Calorie restriction turns on sirtuin genes that code for endogenous antioxidant enzymes and neurotrophic factors like BDNF, neutralizing reactive oxygen species (ROS), slowing the aging process, and protecting against neurodegenerative diseases like Alzheimer’s.
Receptor upregulation. Brain scans in rats (below) show that after 3 months of restricted eating, D2 dopamine receptors in the brain are upregulated. . This in effect lowers body fat “set point”. Calorie restriction also upregulates GLUT-4 and insulin receptors in muscle and liver.
Fasting and weight loss increase dopamine receptors 
Intermittent Fasting (IF). Fasting for 12-24 hours intervals per dayproduces similar health benefits as general calorie reduction, without activating a starvation response or risk loss of lean muscle. A “cycling” approach may optimize the secretion of (and sensitivity to) hormones such as insulin, leptin, ghrelin, cortisol, and thyroid hormones. For many, eating less frequently is easier than eating less at each meal; with time it naturally suppresses between-meal hunger. 
The allergy epidemic is frequently blamed on the profusion of pollutants and toxic man-made chemicals in modern industrial society. But historical studies indicate allergies have become pandemic as our environment has become cleaner.
The Hygiene Hypothesis holds that inadequate exposure to allergens in childhood may be depriving our adaptive immune system from developing properly, failing to develop normal tiers of IgG, IgA and IgM antibodies. The undertrained immune system tends to rely on the “emergency” IgE system, resulting in allergic response when confronted with normally harmless foreign bodies like pollen, dog hair, or peanuts. 
How to eliminate allergies. The conventional advice given to allergy sufferers is to avoid exposure to allergens and use antihistamines. Allergen immunotherapy takes the diametrically opposite approach: Patients are given tiny amounts allergen in shots or sublingually. Exposure is then slowly increased in a systematic way. The emergency IgE response is thus dampened by stimulating production of an allergen specific IgG that blocks the IgE response and modulates the helper T cell response. Allergen immunotherapy has reversed allergies to peanuts and other foods in children. 
Is myopia a result of nature or nurture? While certain populations may be genetically predisposed, studies show that nearsightedness is tied to environmental factors like increased schooling and close work. A multi-generational study of a Eskimos revealed a statistically significant downshift in mean refractive state, from +1.8 diopters (hyperopic) in the older (unschooled) generation to -2.1 diopters (myopic) in the younger (schooled) generation. 
The Incremental Retinal Defocus Theory (IRDT) provides a plausible explanation for myopia induced by near work.  Effort by the retina to focus on near objects slows the rate of retinal neuromodulator proteoglycan synthesis in scleral tissues, causing axial elongation of the eye. Repeated cycles of “near work” induce axial growth that leads to permanent myopia. This has been further confirmed in studies of chicks and other animals in which axial elongation and myopia could be rapidly induced or reversed by respectively fitting them with plus or minus lenses.
How to reverse myopia. Conventional “correction” of myopia by fitting the eye with concave (minus) lenses provides short term relief, but at the cost of inducing progression of the underlying myopia. It is as futile as trying to “strengthen” a weak leg by prescribing crutches.
Anti-corrective lenses are the hormetic solution. Myopia is reduced by inducing a slight myopic defocus or “underaccommodation”. This can be done using reduced prescription minus lenses for distance viewing, and using plus lenses (or the naked eye) to read text at the “blur point” – the maximum distance beyond which the printed word just begins to blur. 
Myopic defocus induced by a convex (+) lens on a myopic eye. From DeAngelis , p. 38
THE BLOG: HORMETISM
Getting Stronger is a blog about the philosophy of Hormetism, based on the application of progressive, intermittent stress to overcome challenges and grow stronger physically, mentally and emotionally.
Some popular blog posts:
- Cold showers
- Improve eyesight – and throw away your glasses
- Intermittent fasting for health and longevity
- Does insulin make you fat?
- Change your receptors, change your set point
- Obesity starts in the brain
- How to break through a plateau
- The paradox of barefoot running
- The case against antioxidants
- A cure for insomnia?
- Overcoming addiction
- Calabrese, E.J. and Baldwin, L.A. “Hormesis as a biological hypothesis”. Environ. Health Perspect. 106 (Suppl 1): 357-362, 1998.
- McCay, C. M.; Crowell, Mary F.; Crowell. “Prolonging the Life Span”. The Scientific Monthly. 39 (5): 405–414, 1934.
- Thanos, et. al. “Food restriction markedly increases dopamine D2 receptor (D2R) in a rat model of obesity…”. Synapse. 62 (1): 50-61, 2008.
- Herring, Bert W. The Fast-5 Diet. http://www.fast-5.com
- Ruebush, Mary. Why Dirt is Good. New York: Kaplan Publishing, 2009.
- Groopman, Jerome. “The Peanut Puzzle: Could the conventional wisdom on children and allergies be wrong?”. The New Yorker, p. 26ff, Feb. 7, 2011.
- Young, Francis A., Leary, George. A. “Ocular Biometry of Eskimo Families”, Primate Research Center, Washington State University, Pullman, Washington, 1973. (Statistical analysis courtesy of Otis Brown).
- Hung, George K. and Ciuffreda, Kenneth J., “Incremental retinal-defocus theory of myopia development”. Computers in Biology and Medicine. 37 (7): 930-946, 2007.
- DeAngelis, David. The Secret of Perfect Vision. Berkeley: North Atlantic Books, 2008.