The Origins of Health

Where do these things called diseases come from?

Mark Pettus, MD

It should not come as a surprise to anyone that the health of Americans is not very good. In fact, we rank below many other nations (17th in a recent 2013 study) in the world with respect to longevity and illness despite spending far more per capita than any other country on the planet. Those of us who work in health care are painfully aware that our system is poorly designed to create health and wellness. So it is not surprising that despite spending over $2.6 trillion in 2013, we continue to see an explosion of growth in diabetes, cardiovascular disease, cancer, autoimmunity, depression, Alzheimers, etc.

While we confront an unprecedented burden of chronic complex disease in the US, we are living at a time of extraordinary growth of knowledge and insight with respect to how we function as biologic organisms. These insights are challenging long-held views about what drives disease and are transforming our understanding of our capacity as humans to become true masters of our lives. Exploding disciplines like epigenetics, nutrigenomics, the microbiome project, and the mind-body neurosciences are suggesting human biology to be a dynamic and adaptive dance between our genes and the environment our genes are in relationship with.

I have come to appreciate that much of what explains the epidemic of chronic complex disease can be more clearly understood when examined through an evolutionary biologic lens. Our genes or our Book of Life have not changed much since our hunter-gatherer ancestors roamed the African savannah. Our environment, on the other hand, has changed withlightning speed over the last 3-4 generations. From changes in our food supply, to lack of movement, disrupted sleep-circadian rhythms, environmental toxins, and unprecedented stress, our genes and the expectations they have for the an environment they are accustomed to, now confront a very unfamiliar landscape.

Consider this. It is estimated that approximately 200,000 years ago, modern humans hit the scene. That means each of us had approximately 7,000 generations precede usand they did. Each lived long enough to reproduce and have offspring that live long enough to reproduce and have offspring that lived long enough to reproducegeneration after generation, handing down a close proximity to your Book of Life6,997 generations latergrandma and grandpa, mother and fatherand now you. You are the lucky recipient of a Book of Life that has been fine tuned to be perfectly adapted to an environment that looked very different from the one we currently inhabit.

I believe most chronic-complex disease can be best understood as a growing mismatch between gene and environment. And what is very deceptive about this mismatch is that many environmental inputs in our lives that we would accept as normal and safe, may in fact, turn out to be novel, new to nature threats. These modern threats might take the form of:

  • Sugar and fructose (we consume more than ever)
  • Refined carbohydrate dense foods e.g. bagels, chips, bread, pretzels, pastries, soft drinks, etc.
  • Gluten and perhaps for some, many grains (grains came along only 10,000 years ago-a blink of an eye from an evolutionary biologic perspective)
  • Hydrogenated oils and industrial seed oils e.g. corn, safflower, canola, sunflower, etc.
  • Stressors from work, strained relationships, conflict, caregiving, finances, raising teenagers
  • Sleep deprivation and altered circadian rhythm from stress, artificial lighting, sleep apnea from obesity, meds, shift work, etc.
  • Environmental toxins
  • Social isolation and loneliness

To name a few.

These radical environmental changes have outpaced our capacity for adaptation. As a consequence we see altered gene expression patterns, altered cell biology, changes in organ and ultimately human biologic systems. Most chronic diseases have evidence of systems-metabolic dysfunction like:

  • Inflammation- a revving up of immune function
  • Altered mitochondrial function- where we make energy and manage our metabolism
  • Altered hormonal balance e.g. cortisol, thyroid, adrenal and sex hormones
  • Alterations in our bacterial ecosystems on our skin, in our mouths, and perhaps most importantly in our guts
  • Alterations in detoxification and how we neutralize the burden of these new to nature molecules

These metabolic challenges over time, become these things we call diseases e.g. diabetes, heart disease, cancer, autoimmunity, depression, etc.

By more consciously aligning our environmental inputs with what our Book of Life has evolved to be in relationship with, one begins to see a shift toward balanced biology. As our biology begins to normalize, so does our health. Our biology becomes our biography.

In my next blog post well explore thegame-changingscience of epigenetics and how our lifestyle choices influence the expression of our DNA.

National Research Council and Institute of Medicine. U.S. Health in International Perspective: Shorter Lives, Poorer Health. Washington, DC: The National Academies Press, 2013