I am in Bogotá airport, in a fast-food restaurant that could be a fast-food restaurant anywhere in the world. On the table in front of me is a sheet of thin green paper, a place mat that doubles as an advert for a range of calorie-laden delights, including Jakobos and Monchers, which would appear to be deep-fried chicken nuggets impregnated with a bolus of bright yellow cheese. What I thought might be the least energy-dense option came with a jagged mound of fries. These are now calling to me from my otherwise cleaned plate, which I have shoved to the other side of the table so as to be as far away from me as possible. Although I still have nine hours of seating and eating ahead of me on my flight, I am already sure that my personal energy balance is in unhealthy credit.
Looking out over Bogotá airport, an enormous playground of dun-grey concrete squares etched with yellow and white lines in curves and tangents, dotted with stubby trucks with tractor wheels dragging huge shark-nosed planes behind them, it strikes me that airports must be the most energy-dense environments on earth. Bright red tankers pump fossil fuels through thigh-thick hoses into the wings of waiting aircraft, while shiny steel catering containers are loaded like military coffins into their bellies. Their calorific contents will be mechanically exhumed shortly after take-off to feed the rows and rows of neatly polarized, functionally paralysed, seated passengers.
I am on my way back to London after a month in Colombia visiting the trauma hospitals taking part in an international clinical trial (the CRASH 2 trial) that we hope will provide doctors with an effective treatment for life-threatening bleeding, most of which is caused by car crashes and violence. Most of the thinking for this book was done in Colombia, early in the morning, on bus journeys between cities, or late at night, while winding my way home from the emergency department of Hospital Universitario San Vicente de Paúl in Medellín. I have spent most of my medical career treating or researching energy-related health problems, but in recent years I have come to see they are nothing more than different manifestations of the same basic planetary malaise.
Worldwide, over a billion adults are overweight and 300 million are obese. One-third of the US population is obese. Government scientists predict that by 2050 more than half of the UK population will be obese, making the UK ‘a predominantly obese society’. Australians, Argentines, Belgians, Bolivians, Canadians and Chinese – everyone is getting fatter. This will affect our health and our well-being, increasing the risk of diabetes, heart disease, stroke and cancer and taking some of the joy out of living. At the same time, global warming is the greatest environmental threat the planet has ever faced. Climate scientists predict an average global temperature increase of between 1.5°c and 6°c by 2100, depending on the extent of future emissions, possibly reaching a temperature not experienced in the past 100,000 years. This will have dire consequences for plant and animal life and for our health. Even cautious scientists are talking in apocalyptic terms about famine, disease and environmental refugees. That climate change is real and man-made is not in doubt. All that is uncertain is how bad it will turn out to be.
If you think that obesity and climate change are unrelated, you are wrong. The human race is getting fatter and the planet is getting hotter, and fossil fuels are the cause of both. This book is the story of energy. The main characters are sunlight, petroleum, movement, food and fat, with money and greed as minor characters albeit of major importance. The story begins with sunlight and decay and will almost certainly end with sunlight and decay unless we act now.
About 150 million years ago, microscopic plankton suspended in the ancient seas sipped carbon dioxide from the surface waters and with the energy from sunlight produced simple sugars and oxygen in a chemical reaction called photosynthesis. In doing so they had converted light energy into chemical energy. The carbon they had absorbed was incorporated into their biological structures, in the same way that the food we eat becomes part of our bodies. When these tiny organisms died, they sank to the bottom of those prehistoric oceans, where they were covered by mud and sand. Here they rotted and, with heat from below and pressure from above, their carbon-containing remains were cooked into a thick black sludge called petroleum. In energy terms petroleum is sunlight jam. For millions of years this jam was safely locked away in its underground larder, but due to the slip and slide of the earth’s crust some of it seeped out onto the earth’s surface, oozing out of the rocks and up into salt wells.
Apart from the evolution of man and the ascendancy of his rapacious economic system, not much more happened until about 1850 when a savvy New York lawyer called George Bissell, whilst visiting his sick mother in New Hampshire, dropped in on his old university professor at Dartmouth College. During his visit, Bissell spotted a small sample of ‘rock oil’, also known as petroleum, which had been left there by another of his professor’s former students, who was working in Pennsylvania. Bissell knew that petroleum was flammable and wondered if he could make money marketing it as a fuel for lamps. He could, and he did, and for many profitable years petroleum lit up the world.
Then, in 1880, Thomas Edison invented the light bulb, and the electricity generation industry grew to power it. Electricity threatened to turn out the lights on Bissell’s petroleum business, and it might have done were it not for the fact that petroleum-powered motor vehicles had begun their ascendancy. Thanks to Henry Ford and the mass production of automobiles, walking and cycling, the usual modes of human transportation, went into a tailspin, slowly but inexorably reducing the amount of bodily energy people expended getting about. This motorization of movement was more than enough to send weight and waistlines on their upward trajectory, but a few decades later petroleum found a niche in our food system and our fat fate was sealed. In the 1940s, petroleum ignited an agricultural revolution that resulted in massively increased food yields. The energy intake of the population became higher than its energy output, and, although the imbalance was slight, the population of planet earth started getting fatter.
The increase in the combustion of petroleum released in huge quantities the carbon dioxide that those ancient microorganisms had absorbed from the Jurassic oceans millions of years previously. And as it built up in the atmosphere, the blanket of carbon dioxide trapped the heat of the sun, steadily warming the earth.
The law of the conservation of energy states that energy can neither be created nor destroyed, only changed from one form to another. In this story we see light energy from the sun captured as carbohydrate by plankton, then cooked and concentrated by the heat of the earth into petroleum, which is concentrated chemical energy. When burned in the engine of a car, this chemical energy is transformed into movement (kinetic energy). Of course, our food energy also comes from the sun and we are biologically programmed to fill up our tanks on a regular basis in order to keep the human body moving. But motorization has meant that petroleum has replaced food as the main energy source for human movement. The unused food energy is stored as body fat and the burning of the petroleum is warming the earth. Global fatness and global warming are different aspects of the same energy problem. A pulse of fossil-fuel energy released from the ground only as recently as the last century has propelled the average human weight distribution upwards, like an earthquake under the sea sends a tsunami towards the shore. At the same time, the carbon dioxide pollution that the burning of petroleum entails is warming the atmosphere, endangering our ecosystems. Our increase in body fat is a threat to our health. Global warming is a threat to our survival.
Neither losing weight nor saving humanity will be easy. To achieve both, each of us will need to become an energy activist and remain so for the rest of our lives. Obesity and climate change are political issues and we need to take political action in response to them. I should say now that political in this context means more than the trivial daily drama played out in the media between republicans and democrats, right wings and left wings. Fat politics is about how and why certain groups of people have made decisions that determine how much we move our bodies, what and how much we eat, and how we spend our time and money. The science and politics of obesity and climate change are accessible to everyone. The reason they are so often misunderstood is that the people who make the decisions prefer it that way. But if we succeed, we will have reasserted our dignity as human beings. Treading more lightly on our planet will make us healthier and happier and richer in every sense of the word.