Wednesday, 2 March 2016

Should we prioritise our health or that of the environment?

Wouldn’t it be great if we could get everyone eating more healthily, so that we all enjoy longer, better quality lives and require fewer medical interventions? And wouldn’t it be great if we could get everyone eating more sustainably, so that we could meet the nutritional needs of everyone on the planet without overburdening the natural environment? These goals have long been run together by the health food industry, endorsing natural foodstuffs as being better, both for us as individuals and for our world. ‘Natural’ implies fewer chemicals to clog up our bloodstreams and our waterways, after all.  But what if all of this is free-range baloney… What if there is natural conflict such that what is nutritionally optimal for human beings tends also to be the most environmentally burdensome, and vice versa. Faced with a choice between producing those foods that promote the health of human populations and those that promote the health of the rest of the living world, which should we choose? 
As a vegetarian since the age of nine, I have many times trotted out the comfortable adage that if everyone were vegetarian the planet would comfortably support its growing population, while being aware deep down that in some habitats vegetarianism doesn't make sense. In rocky steep places you can't grow crops and you're better off farming goats. And I presume the Inuits would never make a living eating salads. In some places meat and/or fish are the only food sources that make sense.
Organic farming has long been the subject of heated debate about whether its benefits to local waterways outweigh the negative fact that as a much less efficient farming methodology, we would never be able to feed the current global population organically (never mind the doubts about whether there are any health benefits for consumers anyway). Lord Krebs has argued that its environmental benefits are oversold - in so far as it ends up using more water and more energy for every calorie produced, we might view it as worse for the environment.

And we've all heard about pristine rainforest being cut down to make room for soya beans. This was rather relished by meat lovers, but I believe the trees were being sacrificed for agrofuels rather than to feed hordes of selfish vegans.

Now an interesting recent study adds new fuel to my concern that my life as a herbivore may not be as saintly as all that. The authors of the study conducted at Carnegie MellonUniversity argued in December that we really are in just the dilemma of my title. The study set out to predict the consequences, in terms of energy use, blue water consumption and greenhouse gas emissions, that would result if US citizens took up the USDA’s 2010 dietary guidelines. The guidelines, aimed at helping individuals achieve a healthy weight, advocate eating more fruit, vegetables, dairy and fish. Their headline findings were that while sticking to the current pattern of foodstuffs but reducing the overall quantities of calories eaten would be good for the environment, maintaining current calorie intake but switching to healthier foods would actually increase energy use, increase blue water consumption and increase greenhouse gas emissions. 

Burgers good, lettuce bad, people!

Of course there are all sorts of complications in carrying out a simple meat vs veg comparison of eco-friendliness. Everything depends on which veg, which meat, where it is produced and how, how much of it is consumed and how/ where it is transported. Even pinning all these things down, we would end up with some values that trade off and are simply incommensurable. Better to support a local farmer or a third-world manufacturer...depends on your value system! Better to save water or save fossil fuels...depends on which one we run out of first! Better to reduce land fill or help the aged.....etc etc.
There would be no sense in assessing what would happen if you try to replace all the calories found in, say bacon, with lettuce. That's a whole lot of lettuce, and few people would recommend doing such a thing. I'm not even sure it would be healthier. A better analysis would compare a diet that gets  say 60% of calories from bacon and 40% from cereal grains, with one that gets 80% of calories from cereal grains and fills the remaining 20% with a variety of different vegetables. Only enough lettuce to add small trace elements to the diet.

This all serves to illustrate the power that we vest in our measurements. One way to quantify how bad a food item is is to measure how many units of an environmental harm (greenhouse gas emission, energy use, water consumption) are created in producing one calorie's worth of the food stuff. But underlying this is the simple assumption, universal within neoliberal economics, that efficiency is always a good thing. If you can produce more calories for less, that's good. But efficiency is the problem with the typical first world diet - people find it too easy to consume too many calories! We need to get them to eat less efficiently. Many diet foods are chosen as such specifically because they are inefficient food sources. Lettuce is mostly water and cellulose - more effort is involved chewing and digesting it than is produced when it is digested. Manufactured diet products often contain ingredients deliberately aimed at making digestion less efficient, so that more of the product is excreted without being used.  Lard, on the other hand, is a rather dense source of calories. Wasn't it always going to be the case that if your study sets out to evaluate foods in terms of their calorific efficiency then calorie-dense foods would do well? The truth is, calories are not the only thing we get from our food, and many of the most efficient foods, calorie-wise, are also the least nourishing: see lard.  Health practitioners don't advocate eating vegetables only because they are less calorific than burgers, but because they also contain many more substances that support health and nutrition. So its not fair to measure the environmental impacts of food items according to their calorie content.  All calories are not created equal.

Accordingly, the model in which unhealthy foods were replaced with healthy foods but the calorie content kept constant makes no sense. The USDA were hoping, presumably, that people would eat vegetables until they were full, not until they had matched the calorie content of their previous diet. And given that healthy foods tend to be much higher in water and fibre than are milkshakes and fries, we can expect that people would feel full after consuming far fewer calories. So they would lose weight and get more nutrients - hooray!

The planet would *probably* be better off if we in the west ceased being such gluttons, stopped wasting so much food, and stopped processing it so highly. The planet would be healthier if we each grew veg in our gardens. It would probably be happier, furthermore, if we each ate only locally produced food, and stuck to fairly simple locally adapted starch crops.

Unfortunately, economics make these changes unlikely to happen any time soon. I was long curious about why the cheapness and healthiness of food often seem in inverse proportion to one another - biscuits: cheap. Frozen sausages: cheap. Instant noodles: cheap. Rocket: eye wateringly expensive, especially given that it has grown like a weed in any garden where I've planted it. Is there a conspiracy by the ruling elite to wield Iceland (I mean the frozen goods retailer, not the country!) as a weapon of suppression of the poor, ensuring that the masses are unable to shift off the sofa? Then a friend pointed out what should have been obvious - the price of a food item is intimately connected to the cost of transporting it. If producers can figure out a way to preserve it, protect it, extend its shelf life and reduce losses during transportation then they can improve their profits. This means adding preservatives, putting it in a can, freezing it. Fresh raspberries, spinach, rocket.....not so much. Plus of course there is a bigger buck to be made from processed food - mixing your labour with the product, to put it in romantic Lockean terms - than from just growing something. 

Until governments do something to tweak these incentives - increasing the price of unhealthy foods using something like a 'sugar tax', or penalising those who add problematic preservatives, perhaps - its likely that the working class will continue to fill their shopping baskets with the calorie-dense, nutrient poor foods that leave some money in their pocket, even as they decimate both our nation's health and that of our planet.

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