A hunter-gatherer’s physiology in a modern world

Perspiration moistened my forehead. In the dust of the trail, I saw the impression of a hoof. Overhead, ravens called. In many cultures, this would be considered a good sign, an indication the herd was near. As I came around a bend, I saw the bison on the rocky hillside below. Their shaggy coats made them look like creatures out of the last Ice Age.

I fully embrace technology. On my wrist I wear a GPS watch which tells my exact location, pace and heart rate. My clothing is the latest in high-tech moisture-absorbing fabric. From the standpoint of my physiology, however, it does not matter whether I am a Paleolithic hunter stalking my next meal or an endocrinologist running a 50-mile ultramarathon. Fortunately for the bison, today I will be shooting only photos (some of the photos are included below).

Many of the diseases we see in our practices are a result of humans having the physiology of a hunter-gatherer while living in a modern world. We eat too much of the wrong things and do not exercise. According the 2007 U.S. Physical Activity Statistics, 51.2% of adults were either inactive or participated in insufficient physical activity; 24.1% reported no leisure-time physical activity at all during the previous month. It is no surprise that obesity, type 2 diabetes, cardiovascular disease, hypertension, dyslipidemia and other diseases are rampant.

I counsel my patients to improve their diet and engage in routine physical activity. They struggle to follow these recommendations with varying degrees of success. Part of the problem is that our bodies evolved to be efficient at storing energy. In the past, famine was never far away. It did not make sense to expend calories unless it was in the pursuit of dinner or to avoid becoming dinner yourself.

Many begin an exercise program sincerely desiring to follow through but drop out later. The first few weeks are the most challenging. Muscles unused for years or decades complain about the increased demands. Some people new to exercise do too much too soon, ending up injured and discouraged.

My advice to my patients is to start out slow, and don’t give up. It may take weeks for the benefits of exercise to be seen and months for a new lifestyle change to become a habit. If the gym or pool is not for you, try something else. It does not matter if you are walking the dog or tending a garden, getting up and moving is what counts. Some believe they are too old and unwell to begin exercising. However, almost everyone can benefit from some form of physical activity, individualized to that person’s level of fitness and health.

While running another ultramarathon, I came across an elderly gentleman shuffling along. I slowed and asked, “How old are you?”

“I’m 84!” he smiled with pride.

“That’s amazing! How long have you been running?”

“Me?” He thought for a moment. “Oh, I started when I was young!” Then with a twinkle in his eye, he added, “I started when I was 65!”

It is never too late for anyone to begin exercising. Some of us might be surprised by the results.

Looking west on Antelope Island in Utah.

Bison on Antelope Island.

Courtesy of Thomas B. Repas,
DO, FACP, FACE, CDE