This week a new paper entitled Leverage Points for Improving Global Food Security and the Environment was published in the journal Science. (Science Daily summary)
The authors focus on the 17 major crops that account for the vast majority of calories produced and consumed, inputs used and environmental impacts from agriculture. The heavy hitters, no surprises. Corn, wheat, rice and cotton. The big impacts that they focus on are water use; carbon, nitrogen, phosphorus and methane pollution of air and water, and tropical deforestation. The major points of leverage included switching from crops for meat production to crops for human consumption, better irrigation, closing the massive yield gap in countries with low performing agriculture, reducing food waste (especially meat waste) and improving the precision use of inputs like nitrogen and water in countries where overuse is the biggest problem.
Two things might surprise folks who get their sustainable ag news from urban reporters and not from academics. The first is that the percentages of over use of inputs in the US are fairly low, while our impact is large, not because our farmers are out of control, but rather that we produce so much freaking food that a few percentage points of over use is a big impact relative to the production in other countries.
The second is the absence of even a mention of pesticides as a major environmental impact anywhere in the paper. Why is this? Because, while pesticides remain a labor issue for farm workers, especially in developing countries, they have improved so much in their mode of action and use in the last half century that they really don’t rate as a major environmental impact, at least in comparison to the big foot issues raised in this paper.
The salience of pesticides as an environmental impact doesn’t come from the size of their effect on the environment, but rather on their psychological impacts. It’s better understood by run of the mill chemophobia. Just as we are more afraid of shark attacks than slipping in the shower, pesticides as poisons or carcinogens have a much greater grip on the public imagination than unsequestered carbon, gulf deadzones, or methane pollution. Tropical deforestation may be the biggest agricultural impact, but there aren’t many mommy bloggers wondering about how it could affect their kids health. As Steve Savage has explained, neither the ag companies that have improved their products nor the environmental groups that have pushed for improvements have much incentive to publicize the changes, so they go unheralded.
The other reason that it has great salience for the general public is because it is the main political football in the culture war between organic and so-called conventional agriculture. Pesticide use, while not absent from organic farming, is the most visible and highly touted difference that sets organic apart. On issues like carbon, methane, nitrogen and phosphorus pollution, organic doesn’t have much to brag about. When it comes to the yield gap, it’s organic that has some splainin’ to do. Thus, a big to-do is made about synthetic pesticides, despite their relatively minor environmental impacts.
There is more to look at in this paper, but the absence of pesticides as a major environmental impact was the first thing that popped out at me.
Josh Bloom in Science 2.0 sets things straight:
The Iowa group studied 60,000 middle-aged women over a ten-year period. Data were accumulated from questionnaires—a notoriously unreliable method of data gathering. But this isn’t a tiny fraction of the problem.
At the end of the study period the group took a look at the health of women who did, and did not drink diet soda. Lo and behold! Of women who drank two or more diet drinks per day, 8.5 percent had some sort of heart disease. But, for women who either drank fewer or no diet drinks that number was only 7 percent. Uh-oh. Smoking gun?
Not even close. Because buried at the bottom of the article is what is really going on: The women who drank more diet soda were less healthy to begin with. They were more likely to be overweight, to smoke, and to have high blood pressure than the other group.
So, let’s correct the headline a bit: “Sick People are More Likely to Die.” Accurate headline, but it won’t sell many papers.
I pray to the gods that there is a special circle in Hell for health reporters.
Quickly and With Some Degree of Confidence
This essay has moved to a new home at FAFDL.org.
On January 14th I published a critique of an editorial by Thomas Sherman and Adriane Fugh-Berman on the Hasting Center for Bioethics blog. A few days later they were moved to respond.
The issue at hand was the retraction of the notorious Séralini rat study.
Sherman and Fugh-Berman held that the retraction was the result of industry pressure and that the retraction didn’t cite reasons that fell within accepted guidelines for retraction [pdf]. I quote them at length to avoid misrepresenting them.
According to the Committee on Publication Ethics, a group that advises medical editors and publishers on ethical issues, particularly, how to handle cases of research and publication misconduct:
Journal editors should consider retracting a publication if:
- they have clear evidence that the findings are unreliable, either as a result of misconduct (e.g. data fabrication) or honest error (e.g. miscalculation or experimental error)
- the findings have previously been published elsewhere without proper crossreferencing, permission or justification (i.e. cases of redundant publication)
- it constitutes plagiarism
- it reports unethical research
There are hundreds of studies that should be permanently removed from the scientific literature, but the Séralini study is not one of them. The FCT retraction announcement very clearly states: “Unequivocally, the Editor-in-Chief found no evidence of fraud or intentional misrepresentation of the data” – and then goes on to say, incredibly, that the study is being withdrawn because the journal’s own review of the primary data show that the results are inconclusive.
Inconclusive? Until a hypothesis is proven, all results are inconclusive.
It would have been perfectly appropriate for the journal to have written an editorial expressing its concerns. Instead, it seems the editors may have succumbed to industry pressure to do the wrong thing.
. . . The retraction of the Séralini study is a black mark on medical publishing, a blow to science, and a win for corporate bullies.
My response was three fold. I agreed that the retraction had a political element, but that it did not seem to be in response to industry pressure.
Second, Sherman and Fugh-Berman had ignored Séralini’s own ethical lapses. The two that I pointed out were his unusual and manipulative press embargo on the study and his decision to allow the rats to die from massive tumors rather than euthanize them. I did not bring up the conflict of interest that the funding of the study represented. This was a conflict of interest not stated in the paper. Séralini wrote in his book that he funneled industry money through CERES to obscure the funding sources for this study. He failed to disclose any conflicts of interest in the paper. That seems like a major no-no to me.
Third, Sherman and Fugh-Berman had thrown around a lot of innuendo about conflicts of interest. While conflicts of interest raise red flags and call for heightened scrutiny, they do not justify jumping to conclusions. Instead, they should be seen as presenting a hypothesis which should be tested. Sherman and Fugh-Berman say, “The quality of Séralini’s work aside, the process by which his paper was retracted reeks of industry pressure.” But how can you judge whether the retraction can be confidently attributed to industry pressure if you put the quality of Séralini’s work aside?
Marion Nestle had a piece earlier this week on how the American Society for Nutrition (ASN), (the organization that publishes the American Journal of Clinical Nutrition (AJCN) and the Journal of Nutrition) should deal with conflicts of interest, especially in the journals that they publish. Her points are sound and I don’t have much to add except that I’ve never understood how the sugar industry has been able to warp the conventional wisdom via sponsorships of organizations, research and research departments but the meat and dairy industries got rolled on fat and cholesterol.
The dairy industry I can understand, because they actually benefited from the low-fat milk nonsense. The admonishment to eat low fat dairy functions more like punctuation than actual advice in standard nutritionspeak. You’d think this would drive the dairy industry crazy until you look at the price of milk in the grocery store. A gallon of full fat, 2% and skim are all the same price. They got to sell people crappy reduced fat milk for the same price as the good stuff and sell the fat as butter, cream and half & half without skim milk as a by product. (Health conscious humans trying to watch their weight are willing to pay more for skim milk than hog farmers looking to fatten their hogs [pdf].)
But it’s seems weird that if the science was for sale, why didn’t the meat and egg people buy it? It should have come cheap as the evidence was mostly on their side when it came to fat and cholesterol.
Conflicts of interest in nutrition societies: American Society of Nutrition
Marion Nestle | Food Politics | November 20, 2013
Big Sugar’s Sweet Little Lies
Gary Taubes and Cristen Kearns Couzens | Mother Jones | November 2012
A Big Fat Debate
Kristen Wartman | Civil Eats | March 4, 2011
What’s Cholesterol Got to Do With It?
Gary Taubes | The New York Times | January 27, 2008
New Review Paper by Yours Truly: High-Fat Dairy, Obesity, Metabolic Health and Cardiovascular Disease
Stephan Guyenet | Whole Health Source | July 22, 2012
How to Fatten Hogs for Market [pdf]
Oregon State Agricultural College | 1930
David Epstein has quick and interesting look at research into the possible role of endocrine disrupting chemicals might be playing a role in weight gain both in humans and in animals. Cats and dogs, rats and mice, apes and chimps are all gaining weight in captivity (this is also seen in feral rats with access to people food). The research is credible, but it raises to issues for me.
The first is that it seems a little too convenient that ALL the endocrine disruptors in the environment are only causing our metabolisms to partition energy into fat storage rather than vice versa. In fact some of them are chemicals used for weight gain. I’d have liked to have seen that addressed in the article.
More centrally, I tend to approach the obesity crisis keeping Occam’s Razor in mind. As guideline, Occam’s Razor holds “among competing hypotheses, the hypothesis with the fewest assumptions should be selected.” The first step is to try to limit the number of possible variable instead of multiplying them. Instead of asking what is causing THIS OBESITY EPIDEMIC and then trying to account for all the variables that make this period of time different than the period that preceded it, you should ask what causes OBESITY EPIDEMICS IN GENERAL and the look at what they have in common. Gary Taubes outlines examples in “Why Do We Get Fat”
1961-63 Trinidad West Indies
A team of nutritionist from the US reports that malnutrition is a serious problem on the island, but so is obesity. Nearly a third of the women older than twenty five are obese. The average caloric intake among these women is estimated a fewer than 2000 calories a day.
Obesity is described as “the main nutritional problem of Chilean adults.” 22% of military personnel and 32 % of white collar workers are obese. Among factory workers, 35% of males and 39% of females are obese.
1964-65 Johannesburg South Africa
Researchers from the South African Institute for Medical Research study urban Bantu “pensioners” older than 60 – “the most indigent of the elderly Bantu,” which means the poorest members of an exceedingly poor population. The women in this population average 165 pounds. 30% of them are “severely overweight.” The average weight of “poor white'” women is also reported to be 165 pounds.
25% of the women and 7% of the men attending medical outpatient clinics in Accra are obese, including half of all women in their 40s. “It may be reasonably concluded that severe obesity is common in women aged 30 to 60,” writes an associate professor at the University of Ghana Medical School, and it is “fairly common knowledge that many market women in the coastal towns of West Africa are fat.”
1970 Lagos Nigeria
5% of men are obese, as are nearly 30% of the women. Of women between 55 and 65, 40% are “grossly obese.”
Cheap refined flours, sugars and oils are sufficient to explain previous obesity epidemics, and I’m don’t see why they are not sufficient to explain this one.
There are some observations in the Epstein article and a longer one by David Berreby in Aeon that can’t be explained the flour, sugar, oil hypothesis. The research around endocrine disruptors is certainly interesting and bears a closer look. I look forward to the EFSA report on BpA later next year. In the meantime, a diet of lots of fruit and vegetables, pulses and whole grains with minimal, minimally processed foods has enough to recommend it without getting overly chemophobic. Obviously, for anyone with an endocrine disorder, a whole different set of criteria are warranted for assessing risk, but for myself, I will continue to believe that the canned tomatoes in my diet are a net plus nutritionally.