While we in the United States like to think we're blessed with the world's best and cheapest food, we've actually let market prices lie to us.

They don't register all the hidden costs of our "factory farming" model, costs that undermine the very sustainability of nature's gifts. Food prices don't count the fact that soil is eroding on prime farmland many times faster than nature rebuilds it, or the marine life we're losing because of nitrogen runoff from overusing fertilizers. The latter has created a dead zone in the Gulf of Mexico as big as Massachusetts and still growing.

The prices don't include the loss of plant diversity that occurs when our seed is supplied by just a few companies aggressively marketing a limited selection or the wells in Midwest states poisoned by farm chemicals.

They don't consider the over-exploited oceans, where extinction threatens one-third of fish species, or the farm families and entire rural communities wiped out by rising farm costs and lower returns.

These are merely the uncounted costs of producing our increasingly unhealthy diet. Eating it adds a host of additional costs, including more than 5,000 deaths each year from food-borne illnesses, even as agribusiness--especially the meat industry--has fought against adding the cost of stricter food safety procedures to the bottom line.

We've boasted that ours is the world's most efficient food system, but no business could stay afloat for long while ignoring its real costs.

Efficiency and sustainability--the maintenance of Earth's gifts to us and our health over time--can no longer be seen as contradictory aims.

Looked at this way, solving our food-related environmental and health crisis doesn't require a change in values. No one wants to destroy our Earth or get sick from what he or she eats. It requires a change in perception.

We have to see differently. We have to see, then measure and count, the real costs of producing food and of our sudden (in historical terms) shift to a meat-based, processed, high-fat and sugar diet.

Just as important, we have to see that we can have the healthy food we need within a more honest framework of cost-counting.

During the last 30 years, agriculturists around the world have been learning to align with nature's genius to create sustainable efficiency--getting the most from nature without destroying it.

With true sustainability we do not have to blanket the planet with pesticides or turn to untried technologies such as genetically engineered seeds that threaten ecological disruption.

Last year, in the first worldwide study of sustainable farming practices, covering 70 million acres in more than 50 countries, researchers noted that applying ecology-protecting methods increased yields substantially. They recorded increases of 150% in root crops. True, in some cases sustainable practices can mean lower yields but, because production costs drop even more, farmers reap better livelihoods. Besides, overproduction, not underproduction, has been the bane of U.S. agriculture.

Once we dispel the myth of efficiency hiding costs, we discover that sustainable is synonymous with real efficiency--getting the most of our resources over time.

To eat well, we don't have to acquiesce to a degrading environment, a tragic loss of species, a heart-rending erosion of family farming. We can redirect tax subsidies to further nonchemical practices and support independent, ecologically committed farmers, without fearing that we'll risk inefficiency-induced scarcity.

We must let go of the false trade-off between protecting the planet and feeding ourselves.

Frances Moore Lappe and Anna Lappe are co-authors of "Hope's Edge: The Next Diet for a Small Planet" (J.P. Tarcher/Putnam 2002).

Copyright 2002 Los Angeles Times

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