Epigenetics is the another biological phenomenon that helps explain the cellular consequences of the mind-body interactions. It can be defined as the study of changes in organisms brought about by modification of gene expression, rather than by alteration of the genetic code in the form of DNA. A simple example involves the boy with the genetic capacity to be tall, but suffers malnourishment and chronic illness during his childhood, so ends up much shorter than expected. The best known mechanism of an epigenetic change is DNA methylation, where a methyl group binds to a base on a portion of DNA, which subsequently renders that region less active. Another common example is histone modification. Histones act as spools around which the DNA winds. If a histone is chemically modified, the DNA expression can change. Early life stress has been associated with epigenetic changes, which can impact the person’s daily functioning. Similarly, anxiety and depression have been linked with similar epigenetic alterations. The example given is the Great Canadian Ice Storm of 1998. This storm killed 35 people, stranded thousands of people and deprived millions of people of electricity for up to 6 weeks. Afterwards, some researchers approached women who happened to be pregnant during the time of this calamitous stressor. They measured biological markers of stress on the women, then followed their babies up until age 13. They found that the ice storm babies whose mothers suffered high levels of stress had more health, behavioral and language problems compared to their age-matched peers. This and other studies suggest that the effects of emotional trauma can be passed down through future generations. (This is important for all of us to realize while we battle through the societal lockdowns caused by our current COVID paranoia syndrome.) At the same time, Dr. Harding was learning more about how some patients did better than anticipated. She cites Dr. George Engel, who proposed that the biomedical model of insufficient to explain human illness. He proposed a biopsychosocial model, with layers of complexity. The model starts with the molecules that comprise the cells, then moves to tissues, then organ systems, then the whole person. Enveloping the person is the family, then the community, then the culture. Continuing outside, we find the nation/state, and then the biosphere. With this wider perspective, we can see that many other processes can affect our overall health. Traumatizing life events can act to poison our health over time. In the 1980’s, Dr. Vincent Felitti was working with obese patients. He was frustrated by the failure of many patients to keep weight off. Somewhat by accident, he discovered that most of the patients
had a history of significant childhood trauma. For these patients, the previous emotional damage was unrecognized as a factor in their current health struggles. This led to the development of the ACE (Adverse Childhood Experiences) Study. The ACE study identified a clear dose-related response, meaning that the greater the severity of childhood trauma, the greater the likelihood of chronic diseases in adulthood. Chronic stress can bring on chronic inflammation, which complicates and shortens our life.
Regular exercise is important. Minimizing the distress that life can bring is also very important for the mind- body connection. Find happiness. It is not always tied to more money. Finding a sense of purpose is the key. Armed with this knowledge, and inspired by the rabbits, Dr. Harding looked for ways to pre-empt these challenges. Part of the approach was seeing all patients as equally deserving of love, regardless of their circumstances. She decries the innate bias that might affect how doctors would diagnose and treat those with a different cultural background. She stresses that there may be hidden factors in the interaction of patients’ physical and mental health. Her approach re-examines the definition of health. The World Health Organization defines health as “the state of complete physical, mental and social well-being and not merely the absence of disease or infirmity.” Another, more functional, definition (as proposed by the National Institutes for Health) is that health is a state that allows the individual to adequately cope with all demands of daily life (implying the absence of disease and impairment). So, how do we get there? Good nutrition is important. Remember the rabbits. Eat more of the foods that they do. And consider eating less. Regular exercise is important. Minimizing the distress that life can bring is also very important for the mind- body connection. Find happiness. It is not always tied to more money. Finding a sense of purpose is the key. Develop and strengthen social ties. Connect with other people. Studies show that social support helps patients heal faster. And that workers who are supported in their workplace are significantly healthier. Get to green spaces more. Studies show that regular exposure to trees, grass, and bodies of water reduces levels of cortisol, lowers blood pressure, and boosts immune function. (It’s like my mother used to say : Go outside and play.) It turns out that nature nurtures us.
AHN Pediatrics-Pediatric Alliance • Winter 2020/2021 • www.ahnpediatrics.org
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