Category Archives: Expert

Do Avatar characters eat cheese? James Cameron’s films may suspend disbelief, but his dairy claims are fiction, not fact.

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In our brave new world, where questioning authority and searching for truth are championed as positive attributes, it is ironic that we tend to follow predictable behaviour patterns when faced with new information. Decisions which we consider to be impartial, or opinions that we hold about controversial issues based on evidence, balance and facts, may prove to be anything but when scrutinised further.

Take, for example, the preponderance of media articles suggesting that meat and dairy consumption are unhealthy – for us, the animals and the planet. One of the most recent, a plea from film-maker and deep-sea explorer James Cameron, plays upon three phenomena relating to decision-making – cultural cognition, bad news bias and confirmation bias.

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We assume that we make impartial, balanced decisions, but we’re far more subject to bias than we may think. Graphic from Capper (2017) Cattle Practice.

Celebrities have been used to sell products, messages and ideologies for centuries, from the Royal Family endorsing Wedgewood pottery in the 1760s, to Bette Davis advertising shampoo in the 1950s and Joanna Lumley now gaining publicity for activist causes. However, fame doesn’t imply any degree of expertise, knowledge or understanding of the issue, just a belief that the solution lies with X, whatever X might be.

Most of us aim to be like our heroes, whether they are famous based on appearance, acting ability, athletic skill or career prominence; thus we are prone to cultural cognition. If I believe that celebrity A believes that something is right/wrong and I aspire to being like this celebrity, I am more likely to adopt their message without question. The fact that a famous Hollywood film maker (and deep-sea explorer – seriously, who doesn’t aspire to be a deep-sea explorer?) has sufficient belief to write an op-ed in The Guardian claiming that we should all reduce meat and dairy consumption, therefore resonates with us far more highly than the same message from a non-famous individual.

The inevitable “this is killing us and the planet” rhetoric adds an extra layer of credibility via bad news bias, in that we are preconditioned to believe negative news over positive news. “Bad news sells” is clichéd, yet true (and explains the popularity of “X Causes Cancer” stories in the Daily Mail) and we need five pieces of positive information to negate each piece of negative information.

Confirmation bias is the final layer in this anti-meat and dairy club sandwich. It’s difficult, if not impossible, to have missed media coverage of potential impacts of meat and dairy consumption on health. If we consciously (or subconsciously) absorb the message that these foods are bad, then Cameron’s claims that “eating too much meat and dairy is making us sick, greatly increasing our risk of heart disease, type 2 diabetes, several major cancers (including breast, liver and prostate) and obesity” agree with our existing bias and we are likely to believe them. However, these claims do not accord with (nor are linked to) current scientific literature on dairy consumption.

This would include, for example, a meta-analysis in Breast Cancer Research and Treatment, which demonstrated a negative association between dairy consumption and breast cancer, i.e. increasing dairy product consumption may be associated with a reduced risk of breast cancer. In addition, a dose-response meta-analysis in the European Journal of Epidemiology reported neutral associations (i.e. no clear positive or negative association) between dairy product consumption and cardiovascular and all-cause mortality. Perhaps even the recent article in Nutrition Research Reviews, which concluded that recommending reduced dairy consumption in order to lower saturated fatty acid intakes (and thus the risk of type II diabetes and cardiovascular disease) would have limited, or possibly negative effects.

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Ice-cream (and other dairy products) may reduce the risk of breast cancer.  

When the subject under discussion is the fictional lives of blue-skinned human hybrids (as per the film Avatar, directed by Cameron), it’s perhaps easier to use imagination than rely on scientific veracity. However, having an evidence basis for claims made in media articles is increasingly important, especially when the claims are made by those who are only prominent for their excellence in other (non-scientific) areas.

In the meantime, eat, drink and be merry over the next two weeks – content in the knowledge that clotted cream with your mince pie will not have adverse health effects, and may even prevent against cancer. Merry Christmas and a Happy New Year!

 

Scare Tactics – Why Do So Many “Public Health Experts” Promote Fear vs. Food?

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pork chop 1How many of us are motivated by fear every single day? We’d like to think that we’re lucky enough to live in a society where we don’t feel afraid. In contrast to inhabitants of many war-torn regions we are unlikely to be shot as we drive to work; when we’re sick we have the luxury of modern medical attention (Obamacare not withstanding); and we can buy almost any food we fancy, at any time of year and feel safe in our food choices… or can we?

Food safety is an underlying assumption of dietary choice within the USA. We buy food based on three major factors: taste, price and nutrition. Safety isn’t a defining factor in choosing between the cheese quesadilla, the chef’s salad or the T-bone steak because most of us have rarely experienced significant negative health effects as a consequence of food choice (aside from the annual Thanksgiving food coma).

Yet so many food commentators, self-proclaimed experts (I read Michael Pollan therefore I am…) or bloggers appear to exist for the sole purpose of instilling consumer fear. Take this recent article in Salon – 9 reasons why we should fear eating steak – apparently it’s riddled with antibiotics, full of heavy metals and likely to give us all mad cow disease. I’m not going to turn this blog post into a thesis, so today will simply address one of the issues raised in the article, and examine the others in future posts.

I’m a scientist by training. In my career to date, I’ve learned that the more controversial the topic, the more important it is to base claims on sound data that is peer-reviewed and published in order to gain trust. If I present data that challenges perceptions, the first questions are always “Is this published in a peer-reviewed journal? Who funded it? How do I know it’s correct?” That is not to say that science is the only way to communicate – it’s not. Yet when making claims, it’s important to have science, or at least logical and biologically-feasible arguments, to back them up.

Yet, if we’re asking a question, even if it’s a loaded question that may instill fear or doubt into the reader, apparently scientific foundation is redundant. Could combining coffee and bagels in the same meal cause impotence? Is breast cancer caused by the rise in popularity of household pets sleeping on their owners’ beds? Is your tiredness really the result of too little sleep, or could it be all the chemicals that “big food” uses every single day? Hey, I’m just asking! Not making a claim, not saying that X + Y = Z, just throwing the thoughts out there. But having read them, how many of us now are thinking about our sexual performance, the potential ill-effects of Fluffy the cat, or how we really do seem to be more tired nowadays? (note that these really are examples that I have invented, I know of no scientific foundation for any of them).

Possibly the most damaging line in the Salon article contained no data. No scientific foundation. Just a question:

Could Ractopamine, added to the food supply in 1997 with little public awareness1, be contributing to skyrocketing rates of obesity and hyperactivity in children?

The FDA approved the use of Ractopamine in swine in 1999. It’s added to the diet of finishing pigs, improving feed efficiency and partitioning more feed nutrients into lean meat rather than fat (as demanded by today’s consumer). Effectively it allows us to produce more pork using fewer resources, but it has been linked to behavioral changes in pigs.

Most of us are aware that childhood obesity is a huge issue (pardon the pun). Many of us know children that have been diagnosed as having attention deficit hyperactivity disorder (ADHD). So does Ractopamine cause these? It’s as likely as suggesting that eating alfalfa hay is going to make us lactate like dairy cows.

Maximum residue limits (MRLs) exist to make sure that there are no human physiological effects of veterinary drugs in meat, milk or eggs from treated animals. Regulatory bodies including CODEX assess potential human effects of a drug residue in animal products by multiplying the average residue level in food by the average intake. For example, if the residue level is 2 micrograms per 100 grams and the average person eats 300 grams of that food each day, the intake would be 6 micrograms. This intake is then compared to the acceptable daily intake (ADI) – the quantity that could be eaten every day for a lifetime without human health risk. This is usually the intake that would have a physiological effect, divided by a safety factor of one hundred. The MRL for Ractopamine in meat is 0.25 parts per million (0.00000025 grams per gram) with an ADI of 1.25 micrograms per kg of bodyweight per day.

If we examine the average pork intake for a 10 year old child in the USA (detailed calculation below) we see that they’d have to eat 13.3x more pork than the daily average to even equal the ADI – remember that’s the intake at which we would expect no physiological effect. For Ractopamine to have a physiological effect, the ADI would have to be increased one-hundred-fold. So the average 10-year old child would have to eat 1,330x more than the average child’s intake of pork, equivalent to 35 lbs of pork per day, every single day (the average adult only eats 48 lbs of pork in a year), for Ractopamine to have a health effect. My little nieces adore pork sausages, but they are pushed to eat two (approx 2 oz) in a day, let alone 35 lbs worth!

Still think that we can link Ractopamine use to obesity and ADHD? We can’t prove a negative, but it’s as tenuous a link as suggesting that we could drown in a single drop of water. So why are public health “experts” like Martha Rosenberg using fear tactics to scare us rather than extolling the positive contributions that high-quality animal proteins make to the human diet? Surely there’s no agenda there….is there?

1Note that all the data relating to this is freely-available on the internet – the “little public awareness” line is simply more fear-mongering.

Details of Ractopamine calculation

Let’s examine an average child’s intake. The average 10-year-old boy in the USA weighs 32 kg (71 lbs) and needs 34 grams of protein each day. In the USA, meat contributes about 40% of protein intake and about 21% of that comes from pork. That means, on average, a 10-year-old boy would eat about 12 g of pork per day (2.9 g protein).

If Taylor eats 12 g of pork each day at the maximum residue limit of Ractopamine (note that this would be unusually high), he’s consuming 12 g x 0.25/1,000,000 = 0.000003 g Ractopamine. His ADI = 1.25 micrograms x 32 kg bodyweight = 40 micrograms, or 0.00004 grams. That’s 13.3x higher than his intake. So a child could eat 13.3x more pork than average, every single day, and not be expected to have any physiological effects. For ingested Ractopamine to have a physiological effect he would have to eat 100 times that amount – 16 kg, or 35 lbs of pork per day. To put that into context, the average adult eats 48 lbs of pork in a year.

Environmental Working Group Proves that “You Can’t Fix Stupid” Proverb is Entirely True.

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Would you replace your hamburger with a soy burger?

Ah, the power of a report from an earnest non-governmental organization, out to save the consumer from themselves. Destined to be selectively quoted for the next 20 years and to prove once and for all that, as the comedian Ron White would say: “You can’t fix stupid”.

Released this week, the Environmental Working Group’s report, claimed not only that everybody should eat less meat, but that “Meat, eggs and dairy products that are certified organic, humane and/or grass-fed are generally the least environmentally damaging…Overall, these products are the least harmful, most ethical choices.” This is a surprisingly intuitive conclusion in that it utterly contradicts the body of scientific knowledge to date, and as the report doesn’t contain any data on anything other than conventional production systems, let alone ethics.

The requisite environmental activist components are there: stylized pastoral scene on the cover and such a liberal sprinkling of emotive words such as “confined” and “polluting” it seems like an ice-cream sundae assembled by a small child with a sugar addiction. It’s even been peer-reviewed by “experts” (as you may have gathered, when reading this post, words in quote marks should be accompanied by an ironic raised eyebrow).

So who are the experts? An RN who teaches “culinary skills and management”, an Assistant Scientist interested in “access to sustainably produced and healthy food”, another whose program aims to “address the environmental and public health impacts of industrial agriculture and promote more sustainable alternatives”. Methodology reviewers were the aforementioned Assistant Scientist, an expert in tropical forests and the daughter of the founder of the Small Planet Institute. What’s the link here? An interest in “sustainability” – which in this case means community-supported agriculture, local food, and nutrition. Where are the experts in livestock production? Who checked with animal and meat scientists, industry professionals, extension agents, nutritionists or processors who can verify that the assumptions made within the report are correct?

It’s a bona-fide report with colorful graphs, acknowledgements, a whole separate report on the methodology (which guarantees nobody will read it) and data! As we all know, data is powerful. According to their “calculations”, lamb has the greatest impact, generating 39.3 kg (86.4 lbs) of carbon dioxide equivalents (CO2e) for each kilo eaten, and beef has the second-highest emissions, generating 27.1 kilos (59.6 lbs) of CO2e per kilo consumed. Cheese generates the third-highest emissions, 13.5 kilos (29.7 lbs) of CO2e per kilo eaten. Everybody knows that data doesn’t lie. Cold hard numbers are based on science. Yet just as I can replace ground beef with tofu and make something that looks like a burger, yet tastes like… soy, so has the EWG have used poor-quality data and erroneous assumptions to create a vegetarian ideology that is a poor substitute for real science.

They claim that if everyone in the U.S. chose a vegetarian diet, it would reduce US carbon emissions by 4.5%.  This is an impressive achievement since the Environmental Protection Agency cites livestock production (including dairy, eggs and horses) in the US as accounting for 3.12% of total emissions. Who knows where that extra 1.4 percent comes from?

The animal component of the report shows a lamentable lack of basic livestock production knowledge. In the beef example, the cow-calf and stocker operations are based on a lot feeding system in Nebraska rather than rangeland production and by-product/forage feeding. All the animals raised are steers (what on earth happens to the heifers?) and there appear to be no bulls in the system, not to mention the lack of dairy calves entering the feedlot and cull beef or dairy cows entering the production chain. Crucially there is no data on herd dynamics, bodyweights, growth rates, and total time required for animals to reach slaughter weight – the most important factors that affect the carbon footprint of a unit of beef.

The lamb system does contain rams as well as ewes, but there is no data relating to the flock, and most crucially, to the lambing rate. US farm flocks average 1.5 to 2.5 lambs per ewe per year whereas range flocks average 1.0-1.5 lambs per ewe. If we compare this to the US average for beef according to the most recent USDA/NAHMS report of 87% of cows producing a live calf, that means we need roughly twice as many beef cows to produce offspring as we do ewes, even considering the fact that lamb produce slightly less meat per carcass on a percentage basis (for a more realistic estimate of meat yields than those quoted in the EWG report, the University of KY have a nice extension publication on the subject).

So here it is, the issue that every single life cycle assessment involving animals and executed by LCA engineers to date misses – the fact that for every day an animal is alive, it needs a certain amount of energy and protein (and therefore feed, land, fertilizers, fossil fuels etc) simply to stay alive. This is called the maintenance requirement and it’s exactly the same principle that leads to that nifty “The average woman requires 2,000 calories, the average man requires 2,500 calories” credo that’s on almost every nutritional label. It doesn’t take a giant deductive leap to realize that if a certain amount of feed is needed to maintain an animal, there’s going to be a certain amount of waste too – which means manure and greenhouse gases. Breeding animals in meat production are the biggest contributors to the total carbon footprint precisely because they consume resources and emit greenhouse gases each day, yet only end up in the human food chain after a number of years, if at all.

If I’m making a bun for my tofu burger, it’s more efficient to cook it in an oven that can produce two or three buns rather than one. Exactly the same analogy applies to breeding herds – a larger breeding herd with reduced reproductive efficiency (i.e. fewer offspring per female), means more resources and a greater carbon footprint per unit of milk or meat. Lamb’s carbon footprint would be expected to be approximately half to two-thirds that of beef given the greater reproductive efficiency, yet the EWG’s estimation has lamb at 44% higher – a clear reflection of the invalidity of their results.

Comparing the carbon footprint of different meat products is an elegantly futile competition in which nobody wins. According to their “data” beef is a better choice than lamb, chicken is better than pork. Yet who fancies chicken Wellington for dinner? Or egg pot pie? Or a pea McMuffin? The idea that we should be happy, saving the world on a diet of tofu and lentils is somewhat ironic given their propensity to produce increased methane from the human gastro-intestinal tract.

Are all 311 million people in the US going to rush to the grocery store and fulfill the EWG’s somewhat desperate cry for Meatless Mondays? Until all human activity can be put into context and the effect of driving to work vs. buying French wine vs. eating an 18-oz T-bone vs. having a third child can be compared objectively, this report is simply another one-week-wonder, destined to be quoted in every vegetarian manifesto and vegan twitter post (presumably vegans don’t tweet, as that would be exploiting birds?) but forgotten as soon as Katherine Middleton wears a new dress on a royal visit or yet another politician demonstrates their indirect support for the pork industry by increasing Google searches for “wiener”.

For a little light relief, here’s Ron White’s take on “Stupid” (please do not watch if easily offended)