“There is nothing more miserable, pointless, expensive and anxiety-provoking than going through life worrying that some food you ate will give you cancer,” writes George Henderson, in his review of a new study which considers the food we eat, and what it’s doing to our bodies.
Accept the one whose faith is weak, without quarrelling over disputable matters. One person’s faith allows them to eat anything, but another, whose faith is weak, eats only vegetables. – Romans 14:1-2
The philosopher Montaigne, on learning about cannibalism, wrote an essay on the varieties of humanity. People everywhere eat differently from us; what they eat may be shocking, but it should not be surprising, because people everywhere are different. New Zealand has passed through a period of conformity marked by dietary guidelines that told us to eat no more than 30% of calories as fat and no more than 10% of calories from saturated fat, as if everyone carried round an analytical laboratory in their pocket or maybe in the lining of their stomach. Naturally a panicked or compliant population ended up buying more of their food in informative packets, packets saying “fat free” or “low in saturated fat”; today you can even buy canola oil that proudly states “half the saturated fat of olive oil”, showing that the whole scheme, whatever its intention, was a race to the bottom for the industrial food complex from the get-go. But such conformity is a thing of the past; today Twitter, Instagram, and YouTube have opened a dietary vista for us almost as shocking as the one that 16th century traveller’s tales revealed to Montaigne.
Here is Shawn Baker, a doctor eating nothing but meat and setting world records for strength in his 40+ age group, with the hashtag #meatheals. Last I heard, none less than Jordan B Peterson was trying this approach – it’s certainly healing his daughter Mikhaila. Here is Dave Feldman, an engineer using a ketogenic diet and halving his blood cholesterol by overeating fat for three days (a result replicable by most who try it, useful for insurance purposes in the US, and one of the most important scientific findings of our era). Then there are the swarms of vegans you already know about, telling you #meatkills though not actually testing the proposal themselves. Every so often one freaks out and shoots up the YouTube offices or becomes Morrissey, but you can still find one or two that have their heads screwed on. There’s even the potato diet (seems to work if you like potatoes and hate absolutely everything else).
Into all this chaos steps Professor John D Potter, the voice of sanity, with the nicely titled Thought for Food: Why What We Eat Matters. In this concise, easy to read volume, published as a pocket-sized, neatly presented paperback in the BWB Texts series, he explains the background to the modern dilemma of non-communicable diseases (essentially, those diseases believed to be caused by pollutants, drugs, sitting around watching TV, and eating too much or the wrong things), in terms of the mismatch between our evolutionary history and the way we live and eat today. He also covers the effect of agriculture on the environment and how our food choices can impact the air, rivers, and climate.
He’s especially good when talking about the relationship between food and social structures: “It is possible to choose good nutritious food and spend very little – but we do not teach or learn this easily. However, it is rather difficult to choose good, nutritious and delicious food by spending only a little. Food, clothing and shelter are basic human needs – rights, some believe – and healthy food is, without doubt, better for our whole society. Therefore, in addition to teaching and learning about food, perhaps we can begin a conversation about how to restructure the way we live, work and earn so that everyone has enough and not so that some have too much of everything and some have too much bad food because that is all they can afford, all they are offered, and all they know.”
Because most of what Potter writes is not only sensible but also interesting, I can almost accept the ultimate direction in which he steers his argument, essentially that the current dietary guidelines, especially in their vegetarian or Mediterranean diet options, are after all the best for us and the planet. Such guidelines were put together before evolutionary theory or climatology got a look in, and designed (as far as health goes) for completely different reasons that almost exclusively had to do with the manipulation of serum cholesterol and blood pressure in what now seem relatively crude and ineffective ways. The academic construct called the Mediterranean diet (though compared with how most people eat today no bad thing), was not actually what the healthy peoples of the Mediterranean ate; they used milk and cheese but never touched low-fat dairy, and where do you think salami, bologna, prosciutto, soppressa or chorizo come from?
Potter introduces some valuable “real food” caveats into these lower fat models, but misses a trick by judging low-carb cuisines to be an evolutionary mistake, a “fad” in the words of the press release, when they are a) the subject of at least as much rigorous research as anything he promotes, b) capable of delivering effects so potent and relatively immediate in the treatment of so many non-communicable diseases as to greatly strengthen his hypothesis that diet is important to health, and c) a powerful light to shine onto some outdated assumptions that underlay the older dietary guidelines and essentially robbed them of efficacy.
Both plant and animal foods supply nutrients: vitamins, minerals, essential fats, and antioxidants; in regular daily consumption (but not so much with supplements, for reasons Potter explains convincingly in Thought for Food) the use our body makes of these nutrients protects us, as far as we can be protected, from diseases like cancer and cardiovascular disease; meanwhile the flux of energy from our food, in the form of the fat and glucose in our blood, in excess can increase our risk. We can clearly see this with colorectal cancers, which might reasonably be expected to have some dietary basis.
The risk for any food, including meat, is trivial compared with the risk from having elevated insulin levels from overeating, or of being deficient in essential nutrients supplied in whole foods – including meat. In fact, in the UK, vegetarians have had a higher incidence of colorectal cancer in years when meat-eating has been a better source of selenium (an antioxidant mineral that’s also low in the New Zealand diet) than plant-based diets. Healthy eating should be about good nutrition, in whatever pattern gives you the most normal appetite, not about cancer-causing foods. And this is a liberating realisation. There is nothing more miserable, pointless, expensive and anxiety-provoking than going through life worrying that some food you ate (or didn’t eat) will give you cancer.
Thought for Food seems to minimise the risks of unintended consequences from meat avoidance. Animal flesh and organ meat, in its natural or traditionally processed state, is one of the most nutrient-rich foods and supplies nutrients not found in any plant foods – B12, retinol, and long-chain fatty acids (especially DHA), as well as other nutrients that can be deficient on a vegetarian diet. These missing nutrients are especially important for brain function. Some people have genetic adaptations to the deficiency of long-chain fats – this adaptation is common in South Asians, but much rarer in Europeans and other peoples without a long tradition of vegetarianism. No-one so far is adapted to B12 deficiency. Meat avoidance in Western populations is associated with increased rates of anxiety and depression, and no gain in overall life expectancy.
New Zealand has a mental health crisis among young people, vegan evangelists unscrupulously target the young, and there are also those young people who are largely vegetarian because they cannot afford decent meat. Are they increasing their risk of mood disorders? No-one knows, seemingly no-one even cares enough in this country to collect data; after all, it’s inherently virtuous to avoid meat, and our experts are promoting this as healthy and good for the environment. No-one in charge wants to rock this boat too much.
The most shocking passage in Thought for Food is the story about the Cincinnati zoo that fed soy protein to cheetahs. Cheetahs can’t metabolise the phytoestrogens in soy (I’m not so sure that humans do it much better). They became sterile. Take a moment to consider what sort of pathological cheapness or healthy-eating delusional thinking it takes for a zoo to feed soy to a cat. This story is ironic because later we are told that the hormones in animal foods may be problematic, but this is unlikely because the levels are microscopic compared with the amounts we make in our bodies every day – an adult male would have to eat 27 cows, give or take a few, to consume the same level of oestrogen that his body makes in a day – or compared with the levels of phytoestrogens in the blood of people eating soy.
Is soy milk gender fluid? Vegetarian pregnancies and phytoestrogens have been associated with a 3.5-fold higher rate (2.2% of births vs 0.6% for omnivores) of hypospadias (the most common malformation of male genitalia), as well as lower male birth rates (male foetuses are harder to bring to term; they’re the canaries in the fertility coal mine). Phytoestrogens are also linked to premature sexual development in girls– something attributed solely to meat in Thought for Food, based on some rather thin epidemiology. Meat eating has not increased – soy eating has increased, from zero in my childhood to soy in food now being an extremely difficult thing to avoid (next time you’re at the supermarket try to find a loaf of bread without it – they even put the stuff in sausages).
Thankfully Potter’s recommendation to eat from a very wide variety of foods, with small amounts of each, and avoid industrially-processed junk, however vegan, might help to limit over-exposure to phytoestrogens.
I’m sorry to say my great-aunt Fay K Henderson played a part in this; she was an early vegan, and even (with my great-uncle Allan G Henderson) helped come up with that word (my family history thus contradicts the provenance Professor Potter supplies for “vegan” on page 68, not a point of any importance). Her 1940s writing for the British Vegan Society sometimes has the esoteric flavour typical of the movement, but she wrote an extensive monograph on the soya bean and gave cooking demonstrations using it (the first of these was in Croydon, on May 6, 1946, to be specific).
There are best-selling books to be written and chilling History Channel documentaries to be made about the dark side of soy. Hitler wanted Germany to run on it and introduced it into Wehrmacht rations; Stalin relied on booming Soviet soy production from the mid-1920s, reaching a peak, remarkable in its day, of 283,000 tonnes in 1931, to underwrite his liquidation of the kulaks (1930-1931), those relatively industrious peasants who owned livestock and supplied milk and meat in a non-collective fashion. But when the kulaks and their cattle and sheep lay dead in their tens of millions, the soy crop didn’t, of course, prevent the even more lethal famine that followed (1932-33), and Soviet soy production was dropped to 54,000 tonnes by 1935.
Although the world’s temperature, climates, and sea level have varied wildly throughout its history, there’s little doubt that their status has been affected recently, and can be affected in future, by human activity. To paraphrase Julian Huxley, humanity has become the managing director of evolution; we’re just not very good at it yet. Ruminant animals are famous for burping out methane, and methane is a potent greenhouse gas. It is also, unlike carbon dioxide, a short-lived one, so levels may fall once current outputs decrease.
Because New Zealand has a small population but is an exporter of dairy products that contribute to feeding the rest of the world, our per capita greenhouse gas contribution is well above average for the OECD; because we have largely switched from sheep farming to more intensive dairying, and from market gardens to crop monocultures, the health status of our rivers and groundwater is critical. As Mike Joy points out, we’re increasingly needing to chlorinate our tap water, yet keep on charitably donating our cleanest drinking water to food and beverage companies like Coca Cola who sell it back it us, with added plastic, for more than the price of petrol.
Potter rightly targets food waste as the main factor in the size of agriculture’s harmful effect on the environment, but there’s a contradiction here with his ideas that fat and saturated fat should be avoided because our ancestors at some arbitrary stage of human evolution ate leaner animals than those we raise today (whenever humans don’t eat, or don’t eat much carbohydrate, their bodies run on animal fat, and any metabolic diseases improve – it’s really not a biggie in this context). When we raise animals for dairy and meat, we can’t avoid producing a lot of food energy in the form of fat as well as protein. If we then eat only lean meat and low-fat dairy, as the Ministry of Health still recommends, this energy goes to waste (it’s still used to make things like cosmetics and explosives, but the modern world surely suffers from a wasteful excess of both of those products). We then need to replace this animal fat, according to the MOH with plant oils (though, to his credit, Professor Potter doesn’t recommend this in Thought for Food), and increasingly it’s being replaced with palm oil, which is an open environmental scandal.
Fat can also be replaced with carbohydrates, such as the rice which, along with fracking and our ever-growing rubbish dumps, is responsible for the recent rises detected in atmospheric methane levels (this rise is not attributable to animals, according to NASA). Either way we need to grow many extra plants to go with the same production of animal foods if we spurn the fat that our ancestors valued. And the same goes for the organ meats. When I was a kid, Mum fed us liver or steak and kidney regularly. If you want to buy these super-nutritious meals today, the RSA is your best bet. Our use of animal foods today is not nearly as sensible as it was within living memory.
Potter, while willing to indulge in a little speculation (an admirable quality in such a writer), mainly attributes the obesity epidemic to the accessibility of cheap sugar and fat, which evolution didn’t prepare us for, and suggests their cheapness be targeted by public health policy. Sugar taxes on soft drink are highly defensible and ought to be tried here, but I sometimes feel New Zealand’s public health experts don’t shop at Pak’nSave often enough. The word used to label cheap fat in a supermarket is “oil”. Butter, cream, dripping, coconut oil, and olive oil – except for the latter, so-called “bad fats” in the ledgers of food virtue – are already much more expensive than the MOH recommended seed oils. People can get addicted to sugar, with ruinous consequences; they do not, so far as anyone has determined, become addicted to fat, no matter how much they like it (but if you add fat to sugar, or deep-fry starch in oil, all bets are off).
Read this book. Buy a copy – it’s cheap enough, informative, and enjoyable to read, and will be especially valuable for vegetarian readers, explaining how and why to avoid the junk-food vegetarianism and fake-meat veganism so common today. For meat eaters, there are arguments in Thought for Food that we do need to know, and after all most meat eaters eat plants too. If, as Potter argues, meat and sugar, alcohol and grains all come at a price, at least we can avoid two or three of those things. But try not to stay in your bubble of righteousness or guilt; read Thought for Food alongside another view, like the gripping detective story of The Big Fat Surprise, which tells how the bias against meat and fat became entrenched in nutrition science.
The science of diet and health, including planetary health, is still in its early stages, with readjustments being made constantly. Potter has laid out his challenge expertly, and there’s nothing wrong with a bit of polemic to get the ball rolling.
Thought for Food: Why What We Eat Matters by Professor John Potter (Bridget Williams Text, $14.99) is available at Unity Books.
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