The ecological cost of what we eat

A case for wise choices that would help the climate as well as your waistline.

Is there a link between our eating habits and the ecological future of our planet – and if so, what is our responsibility? The question may seem academic and somewhat irrelevant, but in the face of today’s pressing needs, it is not. Wherever you may live, look around, and the issue becomes clear. In some parts of the world, people live as though the resources to satisfy their needs are limitless and they have a right to meet those needs, while in other parts of the world, people struggle to meet the real needs of basic survival. The first case involves an excess and so produces waste; in the second, there is simply not enough. Jeffrey Sachs, professor of health policy and management, Columbia University, and special counselor to Ban Ki-Moon, the U.N. Secretary General, argues that if no changes are made to how we manage the planet, “the world is likely to experience growing conflict between the haves and the have-nots, intensifying environmental catastrophes and downturns in living standards caused by interlocking crises of energy, water, food and conflict.”1

Today’s world is a highly interconnected network driven by the exchange of ideas, information, and people. No one can be ignorant or should be indifferent to events occurring around the world; for better or worse, we are increasingly inter-dependent.2 This article deals with only one aspect of that inter-dependency: food. We shall look at modifications to diet during the past 50 years and their impact upon human life, both as short-term consequences and as longer, more profound effects upon nature and people. We will turn our study mostly on the cost of an animal protein-based diet, which can be measured by its impact on agriculture, ecology, water consumption, and health.

The agricultural cost

Consider products of animal origin, particularly from intensively reared cattle, fed in part on food made from soya. On average, each European consumes 87 kg of meat (124 kg in the U.S.A.), and 250 eggs per year. To produce this food requires the equivalent of 400 m2 of soya cultivation. The land required for this for each European consumer corresponds to a surface the size of a basketball court! Countries such as China and the U.S.A., having limited areas of cultivation, target their expansion in South American countries such as Brazil, Argentina, Bolivia, and Paraguay. In Europe, the majority of the soya used comes from the U.S.A. or Brazil. In 2005, Brazil exported 49 percent of its soya production to the European Union.3 The Brazilian government allowed the appropriation of necessary land, while international creditors guaranteed the lowest possible costs to the producers of soya. This, of course, was good news for the Brazilians involved in agricultural production.

But the enormous production of soya to support the meat demands of the Western world has its effect upon ecology and the environment. Nature has its own laws, often cyclic, and cannot escape limitless and constant exploitation. In order to maintain a maximum of soy production, techniques must be introduced that in the short term overcome seasonal constraints, but at the cost of the consumption of energy, water, space, and other valuable natural resources. A continued high rate of use of these commodities could cause unpredictable consequences for the future.

In 2005, Brazil exported 34 percent of its beef production to Europe. The cattle were doubtless fed in part on soya, and the supply of soya was ensured by utilizing a part of the Amazon rainforest for soya cultivation. The effect on the forests was observed by satellite observations.4 Even the meat that is proudly declared in French supermarkets as being “Of French Origin” is likely from cattle fed partly on soya cultivated in other countries.

Such meat production goes on utilizing a vast amount of soya, while in many parts of the world, people are suffering famine and hardship. Meanwhile, an irreplaceable ecosystem such as the primary rainforest of the Amazon Basin is being destroyed. Equally affected is the Amazon Basin that produces the majority of its own rainwater through a complex cycle exclusive to the regions of tropical forests.

Many financial interests are driving the daily reduction in the surface area of the rainforest, such as the increase in industrial culture, the extension of ranches, and the increase in forestry activities. Recently, a climate, energy and environment specialist remarked, “For the world’s markets, the forests are of more value dead than alive.”5 During the past 40 years, close to 20 percent of the Amazonian rainforest has disappeared. This is more than was destroyed since the arrival of the first Europeans 450 years ago. Half of this wood is destined principally for export to the U.S.A. and 28 percent goes to Europe.6

The long-term ecological cost

Amazonian rainforest destruction may seem to be “an affair for the ecologists,” but it should deeply concern us all. This ecosystem, like others, renders service to all of humankind by furnishing products like medicinal plants and wood for local home construction. The ecosystem also supports other economic mechanisms that are often underestimated: the filtration of water, climatic regulation, the control of flooding, the creation of soils, and the well-being of local populations.7 The destruction of the rainforests is undertaken irresponsibly for the planting of large surfaces of soya monoculture in Brazil or palm trees in Malaysia and Indonesia.8 After cultivating a plot of land for several years, cultivation moves to a new area in search of fertile fields. Once the forest has been cut down and burned, the impoverished soil is completely exhausted in as little as two or three years. Then it is oxidized by the sun and its remaining nutrients are washed out by the tropical rainfall. The result is rapid erosion of the soil, sediment deposits in both the rivers and zones normally flooded by the rains, and pollution of the land surface by pesticides and fertilizers with disastrous consequences for the biosphere, flora, and fauna.9

In 1970, hundreds of thousands of people were moved from the states of Parana and Rio Grande do Sul because of soya production. A large proportion of these populations relocated to the Amazon basin, where they were encouraged to cultivate land reclaimed from the forest and subsequently burned. This activity strongly accelerated the degradation of the primary forest, with the long-term consequences for the entire planet that for the present can only be described and not accurately measured. The same problem is also noticed in tropical Africa and in Southeast Asia.10

The energy cost

An animal-based diet also makes its demand to grow agricultural products outside of the natural cycle. Such a demand has created its own energy cost—a huge problem for world agriculture.11 The Western diet, with its high protein content (meats, milk products, etc.) is energy expensive.12 For example, 13 kg of cereals (or 30 kg of forage) are required to obtain one kg of beef. Clearly, a high-protein diet is not profitable from an economic point of view. From an energy point of view, a high-protein diet requires a land surface greater than that for a lacto-vegetarian diet and much more energy.13 The cultivation of most green products, such as grains, fruits or vegetables, requires two calories of fossil-fuel energy per one calorie of food energy, while the ratio for beef can be as high as 80 to 1.14 Knowing that the world’s population will grow beyond nine billion by 207515 and that the land available for agriculture is limited, this poses a grave problem.

What is the answer? Some would recommend,16 particularly in countries with dense populations, an increase in the agricultural output by using chemical fertilizers. Unfortunately, rising oil prices have had a strong effect upon the cost of fertilizers, effectively minimizing their use.17 Moreover, oil reserves are not inexhaustible.18

The water cost

Animal protein has its cost in terms of water use as well. Consider the case of a hamburger versus an apple. The average hamburger has an energy value of 245 kcal, while that of an apple may be 50 kcal. A hamburger meal consists of a bun, some salad, and meat. The production of these elements will require an investment of 2,400 liters of water, whereas one apple requires only 70 liters! Furthermore, the volume of water needed for products in the hamburger sequence has grown by six times since 1990 because of the increased demand for these products in that time period.19 One kg of animal protein requires 100 times the amount of water used in the production of 1 kg of vegetable equivalent.20 This has created a keen competition for access to water between different users: agriculture, energy, industry, and domestic.21

The health cost

The health cost of consuming meat and saturated fat food is well noted in the increase in illnesses such as cardiovascular diseases, diabetes mellitus, obesity, and some cancers.22 According to the World Health Organization, 1.6 billion adults worldwide are either overweight or obese. The problem is not limited to the West alone. It is also on the increase in developing countries where an increase in animal-based protein diet is observed. Alternately, it has been shown that in many Mediterranean countries, a diet containing a relatively high proportion of cereals, vegetables, and fruits and a meat consumption far lower than in northern Europe, is associated with markedly lower rates of chronic diseases.23 Moreover, practices aimed at more-intensive production of any kind of meat can incur a cost in public health through use of food-borne illness, irradiation, the use of antibiotics and growth hormones, lending a greater and more sinister credibility to “we are what we eat.”

Does a vegetarian diet require energy?

Although the cost of producing green products is much lower than that of producing meat, the cost in energy for the production of fruit and vegetables is surprising. The principal costs include fertilizers, phytosanitary treatments to prevent the spread of plant diseases and pests, irrigation, energy used by agricultural machinery, stocking, packaging, manpower, and the cost of transportation. The book Eating Oil24 shows the relation between various diets and the consumption of fossil fuels.25 We have heard of the “green revolution” which, since the 1950s, has promoted a large increase in agricultural production.26 Yet this prodigious progression has come at a price that only now we are beginning to truly appreciate. Prior to the green revolution, most of our food, whether vegetable products or those of animal origin, with cattle essentially grazing on natural vegetation, resulted from the natural photosynthetic process of capturing solar energy. However, with the advent of the green revolution, everything changed, particularly with respect to energy. Now the food found in supermarkets and its price are decided less by the sun than by petrol.27

In the United States, statistics for 1994 indicate that annual food production and distribution for an individual required 1,500 liters of petrol. The figures are comparable for Europe today. This energy can be viewed as follows: 31 percent for the manufacture of non-organic fertilizers necessary for intensive cultivation, 19 percent for agricultural machinery, 16 percent for transport, 13 percent for irrigation, with the remainder being divided between the production costs for pesticides and the storage of harvest. This cost in energy does not include that of packaging, rapid transport to the distributors, the cooling systems involved, transformation of primary foodstuffs, or additives to the cooking. Supermarkets seem so natural, and yet what an accumulated energy they require!

If fossil fuels were inexhaustible, we could continue consuming them as we are. Unfortunately, fuels do have limitations. According to reputable predictions, the known fossil reserves will be depleted in 40 to 70 years.28

Conclusion: What should we do?

The discussion thus far emphasizes the complex interrelations between many macroeconomic factors in the feeding of populations, while explaining the interdependence found at energy and ecology levels. The manner by which we feed ourselves has consequences, whether ecological or energetic, for the entire planet. As Christians and citizens, we should be concerned and ask ourselves the question: How should we react? Action can be undertaken on two fronts, individual and collective. As individuals, we can take simple measures of personal discipline: Why not leave the car in the garage and walk, or cycle those few kilometers to work, to the shop, school, or elsewhere? Why not replace the consumption of animal products with foods having a smaller carbon footprint, which is not only healthier in serving the waistline but also serving the climate.29

These two simple suggestions present several interesting ideas from an economic and energy resources point of view, including the preservation of natural landscapes and the slowing of global warming. They also propose a way to improve personal well-being and cardiovascular health at a low cost. One could go a little further by trying to consume only those products that are available in season, thus avoiding energy wastage by not buying products from other continents and supporting organic agriculture and that of small, local producers. Even if their products are not perfect, they consume less energy than those produced far away.

Sooner or later, this kind of engagement will have its effect on ecology. We can have a positive influence on our environment and the health of the planet.

Raymond Romand (Ph.D., University of Montpellier, France) is Professor of Neuroscience at the University of Strasbourg (France) and former Professor of Biology and Tropical Ecology at the University of Dakar, Senegal. E-mail:


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