Thursday, 24 March 2016

Vegetarian propaganda dressed up as science - welcome to joyless food academia

There is an especially joyless tendency in the world of food academia. This is a world where food is made into a problem - causing cancer and other disease, 'promoting' obesity or destroying the planet. And the main reason for this destruction of any pleasure in food rests with a particular sort of vegetarian - often vegan - activist academic:

"We do not expect everybody to become vegan," said lead author Marco Springmann of the Oxford Martin Program on the Future of Food.

But if they did, they'd live longer and help reduce the changes that are skewing the climate.

"What we eat greatly influences our personal health and the global environment," Springmann said.

Got that folks? You don't have to be vegan but if you want to live longer and save the planet into the bargain then you jolly well ought to be. And the reasons are set out in Dr Springmann's well-funded research:

If everyone ate less meat and other animal products and followed guidelines already recommended for healthy eating—more fruit, vegetables, and whole grains and less meat, salt, and sugar—it would reduce global mortality by up to 10 percent and reduce food-related greenhouse gas (GHG) emissions between 29 and 70 percent, based on predictions for the year 2050, write Marco Springmann and colleagues in their paper published today in the Proceedings of the National Academy of Sciences.

Not, leaving aside that I'm always dubious about research that has very broad ranges ('between 29 and 70 percent') and memorable round numbers ('up to 10 percent'), we need to get into the truth of what Dr Springmann is saying about the economics of food production to understand why he is pulling a whole load of vegan-approved artificial wool over our eyes. The first of this is what we count as part of the contribution from livestock farming - the veggie activists claim anything up to 30% of anthropogenic greenhouse gases from livestock farming making it a bigger contributor than the world's entire transport system.

A more measured figure is:

Recent estimates by the United States Environmental Protection Agency [EPA, Hockstad, Weitz (2009). Inventory of U.S. greenhouse gases and sinks: 1990–2007. Environmental Protection Agency] and the California Energy Commission [CEC—California Energy Commission (2005). Inventory of California Greenhouse Gas Emissions and Sinks: 1990 to 2002 Update] on the impacts of livestock on climate change in the United States and California have arrived at much different GHG estimates associated with direct livestock emissions (enteric fermentation and manure), totaling at less than 3% of total anthropogenic GHG and much smaller indirect emissions compared to the global assessment.

The problem is that things such as deforestation are being included in the calculation as is the use of nitrogen fertiliser to produce cattle feed when we know that the alternative crop would also use said fertiliser - unless we plant trees (an approach that is possible given farming intensification but not with the extensive organic methods preferred by our veggie academic activists). Indeed levels of fertiliser use in arable farming are significantly higher - up to four times greater - than for livestock farming which suggests that levels of Nitrous Oxide would rise under a shift to a diet based on vegetable proteins.

We're told that, of the greenhouse gases produced by agriculture (Nitrous Oxide, Methane and Carbon Dioxide), Nitrous Oxide is by far the most significant in terms of impact:

So the slightly glib assumption that reducing livestock numbers would reduce emissions is, at the very least, open to question as is the oft-repeated statement about the degree to which livestock is contributing to greenhouse gas emissions.

Which, I guess, brings us to health and our veggie academic activists who are terribly imprecise with their 'up to 10%':

For their study, the Oxford scientists “used specific food groups” Springmann told Civil Eats. “Each additional serving of fruit and vegetables reduces chances of heart disease and diabetes,” he explained. “Add more meat and you go in the other direction. It’s almost linear,” he said. Such data, Springmann explained, is found in so many studies that it’s now “basically an agreed fact” that high fat, meat-heavy diets are associated with poor health outcomes.

Now there's a bit of a problem here because we're all living a whole lot longer despite this 'high fat, high meat' diet of ours with some of the highest level of longevity being in the very Western nations that are singled out for vegetarian opprobrium. Indeed the problem is that every one of the world's most long-lived societies has above average consumption of meat. We shouldn't be surprised about this because the thing all these countries share is being relatively rich.

It's true that there's a well-established correlation linking eating red meat and processed meats with bowel cancer. But the increased risk is so small that it simply wouldn't show up in overall mortality statistics:

We know that, out of every 1000 people in the UK, about 61 will develop bowel cancer at some point in their lives. Those who eat the lowest amount of processed meat are likely to have a lower lifetime risk than the rest of the population (about 56 cases per 1000 low meat-eaters).

If this is correct, the WCRF’s analysis suggests that, among 1000 people who eat the most processed meat, you’d expect 66 to develop bowel cancer at some point in their lives – 10 more than the group who eat the least processed meat.

The 'scientists' go on to link meat with diabetes, stroke, heart disease as well as the bowel cancer. The problem, as with every claim of this sort is that, while there's plenty of evidence showing high meat diets correlate with diabetes, this evidence show the increased risk is tiny alongside other risk factors such as being obese. And, as we know, the main factor in the increased incidence of diabetes is mostly down to how we define having the condition and longevity plus incentivising medical professionals to diagnose the condition in the first place.

In the case of stroke and heart disease, the problem is that these problems have been declining pretty consistently for several decades despite an increased consumption of meat. The rate of decline may indeed be faster for vegetarians but there simply isn't a case for saying that a million more early deaths would be avoided if everyone became a vegan. Which isn't really a surprise at all since there's plenty of evidence telling us vegans are less healthy:

Vegetarians have twice as many allergies as big meat-eaters do (30.6% to 16.7%) and they showed 166% higher cancer rates (4.8% to 1.8%). Moreover the scientists found that vegans had a 150% higher rate of heart attacks (1.5% to 0.6%). In total the scientists looked at 18 different chronic illnesses. Compared to the big meat-eaters, vegetarians were hit harder in 14 of the 18 illnesses (78%) which included asthma, diabetes, migraines and osteoporosis
The truth in all this is that we are able - through the careful selection and manipulation of statistics - to show how almost any individual element of diet is either good for us or bad for us. And this results in the sort of crank science presented in this argument (in the case of Springmann et al supplemented by some equally dodgy climate change science and batty economics).

Our food system is not destroying the planet nor is it making us ill. Agriculture and the food industry it supports is, in fact, responsible for the amazing achievement of feeding over 7 billion people using a declining proportion of the world's land and with ever greater efficiency. And as for diet, the right advice is to eat a properly balanced diet - with or without meat. More to the point - and there's plenty of evidence that this too leads to a longer life - enjoy the gathering, preparation and consumption of all the foods nature and human ingenuity provides.


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