How Lettuce-eating Cyclists Kill our Planet

Did the title grab your attention? Cannot believe it is true? It IS true. The dots are there, people just refuse to join them up because of fashion. I need to do more work on researching the numbers of how much damage is being done, and how many are to blame, but let me sketch out the idea here.

Let us start with some simple basics. First, old Einstein pointed out that matter is energy. That means even things made of matter are, essentially, just another manifestation of energy. Everything in our physical universe is energy, in one form or other. Remember this, it is the cornerstone of the argument.

Second, fashions come and go. When in the midst of a fashion, what seems perfectly sensible will, once the fashion is dead, seem very daft. That is why we no longer see people wearing powdered wigs or daubing white lead on their faces. Fashion does not apply to clothes only, it also applies to ideas. White lead was popular because a pale skin indicated someone who did not work in the open air, and was hence more refined. Coco Chanel went on a cruise from Paris to Cannes, and got a suntan. That instigated the idea that a suntan represented wealth and luxury. Instead of wanting to turn white, women started wanting to turn brown. More recently, thanks to medical research, the circle has started turning the other way, as there is nothing sexy about skin cancer. Two of the predominant fashions of this era are healthiness of the individual and concern for the planet’s environment. I say these are fashions not because they are wrong or devoid of meaning, but because human perceptions of them have changed and will likely change again. As such, our perception of how to achieve both goals may be at odds with each other, especially in areas where fashionable thought obscures the real issues.

Getting back to the real issues, and real issue number one is where we get the energy to live our lives without killing the planet. Remember, everything is energy. Some energy sources never get depleted, like the Sun (of course, even the Sun will eventually run out, but we have time to worry about that later), or get used less quickly or as quickly as they are replenished, like hydropower or burning rubbish. Some energy sources get used up far more quickly than they get replenished, like coal and oil. I say “sources” because, ultimately, all of these sources stem from the same source – the Sun. I distinguish the sources based on our day-to-day experience of them (oil is black stuff in the ground, the Sun is a big light ball up in the sky etc).

To be healthy, we humans also need a source of energy. Otherwise we die. We predominantly obtain energy from what we eat and drink. Our food and drink may also provide other raw materials for our well-being, but most of it is consumed for the purpose of providing an energy source. This is why crops may not be a wise alternative to oil. Biofuel may be used to run our cars, but still needs to compete for resources (land, and hence ultimately exposure to the Sun) that may be better used producing food.

The amount of food we need is related to the amount of energy we expend. That is a FACT. It is, to borrow from Al Gore, an inconvenient fact that many people try to gloss over. It is inconvenient to lots of people pushing diet pills, exercise programs, and low-cal substitute foodstuffs. Eating gives most of us pleasure, but in wealthier countries there is the risk of consuming more food than is needed to meet our energy needs. That makes us fat. Similarly, if we ate less than our energy needs, we would get thinner. We may also get unhealthy in various ways, but we would, eventually and inevitably, get thinner. Forget all that advice about eating something for breakfast or selecting the right kinds of food in order to lose weight. In the end, lots of people all over the world still die because they do not have enough food. Do not kid yourself that it all comes down to how you eat, and not how much you eat. The less you eat, the thinner you will get, because you are not consuming enough energy to meet your energy needs. I am not advocating eating less, because your nutritional needs, and hence your health, are much than just a simple what goes in versus what goes out equation, but I am pointing out the equation is fundamental and relevant.

One aspect of healthiness is exercise. If we are active, our bodies work better and, as we age, degenerate at a slower pace. This means, to be healthy, we need to expend energy on exercise. I say “exercise” in the broadest sense of physical action. There is also a narrow sense, of exercise for exercise’s sake. My concern is that exercise, for exercise’s sake, may be good for your health, but otherwise is a waste of energy. It consumes the energy delivered in food, but has no productive outcome other than improving the health of the individual. This may be contrasted with purposeful exercise. In other words, it is the difference between riding an exercise bike in the gym and riding a bicycle to work. In the former, the only goal is to exercise. In the latter, a necessary transportation goal is also realized.

Our diet is another aspect of our healthiness. We need energy, which may be measured in calories, we need water, and we need nutrients. Certain foods, like lettuce, are low in calories, high in water content, and rich in nutrients. This makes lettuce quite a fashionable food, in the sense of being a good choice for healthy living. But it is a terrible food for the environment. Why? Because the total energy used to produce and distribute a lettuce, like any foodstuff, is not the same as its calorific content. Lettuce contains energy, which we can access by eating it, but some energy used in the production of the lettuce, and most obviously in getting the lettuce to the person who eats the lettuce, does not add to the calorific content of the lettuce itself. Think of the energy spent planting the lettuce, or tilling the land, or involved in making or spreading fertilizer or pesticides, or collecting the lettuce, or building storage capacity for lettuces, or transporting the lettuce, or chilling the lettuce whilst being stored or transported, or packaging the lettuce, or even in the energy you consume to eat the lettuce. All of this energy is used in order for you to eat the lettuce, but none of it goes into, or comes out of, the lettuce itself.

Can you see where I am going yet? That lettuce, which may be so fashionable, may arrive on the plate of a wealthy person only because of a lot of energy-expensive activities beforehand. Lettuce is particularly energy-expensive, because it is big, bulky and is mostly water. If you split the lettuce into nutrients and water, and only transported the nutrients, you would use a fraction of the energy needed to transport the whole lettuce. We already have more efficient ways to transport water than in the form of lettuces, so human needs could be satisfied at far less cost to the planet if people drank water from the tap and ate the nutrients than if they ate a lettuce. It would be less fashionable. It would not “feel” as healthy. But it would be a lot better for the environment, by reducing energy consumption, particularly that spent on transporting the lettuce. When you factor in that your lettuce, because of largely inefficient distribution chains designed to give you nice-looking lettuces when and where you want it, has quite probably had to travel from a foreign country to get to you, you end up with lettuces that consumed over a hundred times more energy to get to you, than you get when you consume them.

Lettuces are not the only culprits in the criminal roll-call of energy-wasting foods. They say that eating celery consumes more energy than is contained with the celery. That may be great if you want to lose weight, but represents a wasteful process from the perspective of conserving energy.

Energy wastage in food production and distribution is one problem we need to tackle if we are to help the planet, even if it means not having food that looks and feels so healthy. Energy wastage due to consuming food for pleasure is another side of the equation, even if the pleasure is related to “healthy” foods. It is easy to be critical of fat people who eat poorly. Being fat may lead people to consume more of other energy sources – they weigh more so consume more fuel to transport, they need bigger clothes, and they may eventually consume energy in terms of drugs and medical treatments. But some of the “bad” foods, like sugar, are bad because they are highly concentrated forms of energy. Somebody (probably me… hopefully somebody else) needs to do an energy audit comparing how much energy is expended producing and transporting “bad” foods versus “good” foods. It may be that the bad foods are better for the planet, if they consume a lot less energy relative to the calorific content provided to the person eating them.

Even if you cycle to work, as opposed to cycling to lose weight, you may be harming the environment more than helping it. It takes energy to fuel you. You expend that fuel when riding your bike. If you did not ride the bike, you could have ate less. If the energy you use riding the bike comes from lettuces, and those lettuces come from another country, then an awful lot of energy was expended prior to you getting the little bit you use to turn the pedals. Most of that energy will have come from non-renewable sources. Factor all those numbers into any equation for how good the bike ride is for the environment. Then compare those numbers to the numbers involved in drilling for oil, transporting the oil to your car, and then used in powering the car. Cars are heavier than bikes, but oil is a very concentrated source of energy. It may be that the total energy cost, in terms of the non-renewable energy expended, is lower if you drive to work. I am not saying it is, I am just saying I have not seen anyone do the maths, and it is a long way from obvious as to which equations would represent the most efficient use of our non-renewable sources. It does not matter that the fuel in the car (petrol, gas, diesel, LPG, whatever) is 100% non-renewable and that the fuel in you (lettuce, strawberries, white sugar, celery, hamburger, Pepsi, whatever) is 100% renewable. What matters is the total non-renewable energy cost in getting the necessary amount of fuel to you, including the energy expended on production and distribution. In short, powering your bicycle with lettuces may have a higher total carbon cost than driving your car.

Of course, the carbon cost of the lettuce, and of your diet in general, rather depends on where your food comes from. If it comes from your back garden, then the costs will be lowest (though we still need to factor in the energy cost of tools you may use, fencing to keep out animals etc). If it comes from a local farm, it will be low. If it comes from the other side of the world, it will be high, although we should avoid over-simplification. It has also been reported that the production of New Zealand lamb is so much more energy efficient than the production of lamb in the UK, that New Zealand lamb represents a lower total energy cost to UK consumers than UK lamb does.

If we want to eat healthy and save the planet, it would be a good idea to print the total non-renewable energy costs involved in production and distribution on those expensive and obsessive labels so loved by nanny governments. Until that time, the safest bet is to eat in moderation, grow your own food, and pay attention to where food comes from. Digging up the garden is a more productive use of energy than pretend rowing at the gym, so perhaps you should swap one form of exercise for the other. There must be a fair few people who feel very self-congratulatory when they ride their bicycle into work, and then eat a big salad for lunch. For all we know they are killing the planet far more quickly than a 4WD driver who ate a small burger from Burger King. As I said before, I need to do a lot more research before reaching conclusions, and there are many variables, but if I sowed a seed of doubt, that is enough for now.

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