Ultimately, every paradigm is founded on faith. Faith in the process for some. Faith in the evidence, for others. Some systems survive, sustained by their evident logic and internal consistency. Adherents adopt a near-religious protective shield to deny data inconsistent with the paradigm. Ultimately, mounting evidence becomes too strong to deny and the old world view can disappear quickly.

We often describe adherents to the “salt hypothesis” that reducing dietary salt will improve health in such terms. There may be an even better example (nah, probably not better)

Like certain questions of public health, some environmental propositions are so logical and internally-consistent that they resist new evidence. This is especially the case when the proposition is bolstered by strong special interests. In the salt arena, we saw this phenomenon several years ago when the Natural Resources Defense Council, spurred by strong fundraising appeal, argued that a proposed Pacific coast saltworks would remove so much salt from the ocean bay that wintering newborn whale calves would have insufficient buoyancy and drown. The fact that the whales thrived near the saltworks was ignored.

The same logic held that since salt was related to blood pressure and low blood pressure populations had fewer heart attacks, we should expect improved cardiovascular health by putting the entire population on a “low salt” diet. That easy assumption has been disproved by now double-digit numbers of studies measuring the health outcomes of low-salt versus normal-salt individuals. But those facts are for another story.

This time the issue is energy and the environment and the evidence in question pertains to ethanol. Ethanol is touted to replace gasoline in our cars and trucks. Its heavily-subsidized production has vastly expanded the demand for American corn. In fact, the enormous volume of grain shipments that once made the Mississippi a southbound “superhighway” (and subsidized less expensive up-river shipments of salt), has almost disappeared; corn is trucked to nearby ethanol plants in our national push to reduce carbon-based “greenhouse gases.” Since the “road to the White House” runs smack through subsidy-loving Iowa, the federal government is ethanol’s biggest booster. It’s bipartisan.

In recent years, skeptics have pointed out that it takes more BTUs to raise the corn and process it into ethanol than the ethanol yields. No matter.

Now skeptics have another argument. A recent article in Environmental Science & Technology (Web published last month; in hard copy next Wednesday) points out flaws in previous calculations of the amount of water required to grow the corn to feed the ethanol plants. While the new math may discomfort the corn growers of Iowa and Illinois, the researchers from the University of Minnesota documented huge differences in water requirements based on irrigation practices. While it may make some sense to use rainfall-nourished Iowa corn, it borders on the criminal to allow ethanol production in water-starved states like California. As policy-makers drive ethanol production higher, water used to make ethanol has increased 246% from 1.9 trillion liters to 6.1 trillion liters in just the past three years (whereas ethanol production has “only” increased half that much, 133%).

Six years ago, other researchers estimated that it took 263 liters of water to produce one liter of ethanol. Last year, the National Academy of Sciences tripled that estimate to 784 liters. This new study by Yi-Wen Chiu, Brian Walseth and Sangwon Suh says the true water cost varies from 5 liters of water for a liter of ethanol all the way up to 2,138 liters of water for each liter of ethanol; the general trend follows rainfall with the East being more water-sufficient and –efficient and the drought stricken West terribly water-inefficient. By state, Ohio can produce a liter of ethanol for 5 liters of water; Iowa, 6; Kentucky, 7; Tennessee, 10; and Illinois, 11. In contrast, Wyoming requires 1,354 liters; New Mexico, 1,427 and California a whopping 2,138.

Over the next half century, we believe that our current preoccupation with energy supplies will yield to burgeoning alarm about our dwindling water supplies. And the poster child for water conservation is California. So tell us again: why are we subsidizing ethanol production in California when it requires better than 500 times more water than in the Mississippi basin and forces draconian lifestyle controls in many California communities?

The ethanol house-of-cards is glued together with federal subsidies, so it may last even longer than federal public health nutrition policy now suffering body blows as new “health outcomes” studies fail to identify a health benefit for all the over-hyped recommendations and new evidence is emerging that consumers possess a “hard-wired” appetite for salt – just like livestock and poultry which science we’ve understood for the better part of a century.

The next question is whether “Change!” and “transparency” will allow a full discussion of these new facts of energy and nutrition recommendations and changes to those policies.