The Wisdom in the Food

The food on our plate is no longer just our problem. It is, more and more strongly the evidence suggests, a letter we are writing to people who do not yet exist.

A dentist in the Hebrides

In the summer of 1931, a Cleveland dentist named Weston A. Price boarded a ship to the Scottish Outer Hebrides with a camera, a notepad, and a question that had been troubling him for years. He had spent decades watching his patients' teeth deteriorate — cavities, crowded mouths, narrow jaws that seemed barely large enough to accommodate the teeth trying to fit inside them. What troubled him most wasn't the decay itself. It was that it seemed to be getting worse. And not slowly, generation by generation, in the way one might expect a gradual environmental shift to show up. It was accelerating. Children's mouths looked noticeably different from their parents'. Something was changing, and changing fast.

Price was not the kind of man who found that sort of observation comfortable and left it alone. He was systematic, meticulous, and possessed of the particular stubbornness that drives people to spend their own money sailing to remote islands in search of an answer. His theory — unformed at this point, more of an instinct — was that the problem wasn't in the teeth. It was in the food.

What he found on the Isle of Lewis would set the tone for a decade of travel that would take him to Swiss mountain villages reachable only by foot, to Inuit communities on the Arctic coast, to pastoralist tribes in Kenya, to the rainforests of Peru. In each place, he did the same thing: he examined mouths. He photographed faces. He recorded what people ate. And in each place, he found the same arresting contrast. Among communities still eating their traditional diets — whatever those happened to be, and they varied enormously — dental health was remarkable. Cavities were rare. Dental arches were broad and well-formed, faces symmetrical, teeth straight without any intervention from anyone like Price. Then he would find, often in the same community, sometimes in the same family, those who had begun eating what he came to call "the foods of commerce" — white flour, sugar, tinned goods, vegetable oils, polished rice. And the mouths told a completely different story.

This was the finding that stopped Price in his tracks, and that should stop us too. Because he wasn't documenting the slow erosion of health over centuries of gradual dietary change. He was documenting something that happened to living people, to their children, visibly and measurably, within years of a single dietary shift. The photographs he brought back — which you can still find reproduced in his 1939 book Nutrition and Physical Degeneration — are not easy to look away from. Broad, even smiles beside crowded, narrowed arches. The same genetic heritage, the same village, separated not by centuries but by the arrival of a trading post.

Price never found one perfect diet. That, in a way, was his most important finding. The Inuit thrived on almost no plant food whatsoever — blubber, organ meats, raw fish. The Swiss mountain villagers ate rye bread, raw dairy, and whatever they could grow in a short Alpine summer. The Maasai drank blood mixed with fermented milk. What these diets shared was not a particular food or macronutrient ratio. They shared something harder to name: an intimacy with their food sources, a set of preparation traditions refined over generations, and a striking nutritional density — particularly in fat-soluble compounds — that modern Western eating had largely abandoned.

Among those compounds, Price identified something he couldn't name. He called it Activator X: a fat-soluble substance present in grass-fed dairy, organ meats, and certain fish eggs, that seemed to work synergistically with vitamins A and D to drive mineral metabolism — the absorption of calcium, phosphorus, the building of bone and tooth. He knew it was there. He could measure its effects. He just couldn't identify it. It would take another sixty years for nutritional science to catch up with what Price's empirical eye had already found. Activator X, we now know, was vitamin K2 — a compound still underrepresented in mainstream nutritional guidelines, still absent from most people's awareness, still not fully understood in all its interactions. Price knew it mattered in 1939. We're still working out why.

This gap — between what traditional peoples demonstrably knew worked and what nutritional science could explain — is not a minor footnote. It is the central problem with the way we have come to think about food.

Pottenger's bridge

Price was an observer. His laboratory was the world, his instruments a camera and a notepad, his subjects entire communities living and eating in ways their ancestors had for centuries. The findings were compelling precisely because they were real — real people, real mouths, real generational change. But observation, however careful, leaves room for doubt. What if there were other variables? What if it wasn't the food at all?

Around the same time Price was travelling, a California physician named Francis Pottenger Jr. was asking similar questions in a rather more controlled setting. Pottenger was studying adrenal hormones in cats — a fairly narrow biochemical inquiry — and needed healthy animals for his research. He began to notice something inconvenient. The cats fed cooked meat scraps from his kitchen were not as healthy as the ones receiving raw meat. They were surviving. But they were not thriving. And when they reproduced, their kittens were less robust still. By the third generation, the decline was dramatic: poor coat quality, skeletal abnormalities, reduced immune function, reproductive problems, behavioural changes. Some third-generation females were so aggressive they were difficult to handle. Others were so passive they barely reacted to stimulation at all. A population, in three generations, that had lost something fundamental.

Pottenger ran his cat experiments for ten years, across multiple generations and hundreds of animals. He also tested the effect of raw versus pasteurised milk. The results followed the same pattern: processed food, generational decline. Return to raw food, and the population slowly — over several generations — began to recover. Not immediately. The damage, whatever it was, took time to undo.

The study has real limitations, and it is worth being honest about them. Cats, unlike humans, cannot synthesise taurine — an amino acid destroyed by cooking — so some of the observed decline may have been taurine deficiency rather than a more general principle about processed food. The experimental controls were imperfect by modern standards. Pottenger himself was careful not to overclaim. But the directional finding — that the quality of nutrition across generations affects the health of subsequent generations in measurable, physical ways — would not stay a curiosity for long. Because science was quietly building toward a mechanism that would make Pottenger's cats look less like an anomaly and more like an early signal.

The software, not the hardware

For most of the twentieth century, inheritance meant one thing: DNA. You got half your genome from each parent, those genes expressed themselves, and that was more or less the end of the story. The environment could damage your health, certainly. But it couldn't rewrite what you passed on. The hardware was fixed.

Then biologists started finding things that didn't fit.

Identical twins — same DNA, same womb, same early environment — diverging dramatically in health and disease risk as they aged. Children born to mothers who were starving during pregnancy showing different metabolic patterns decades later, patterns their own children sometimes seemed to carry. Laboratory animals whose mothers were fed particular nutrients during pregnancy producing offspring with different coat colours, different cancer susceptibilities, different lifespans — without a single letter of their DNA changing.

The explanation turned out to be written not in the genome itself but on top of it. Epigenetics — from the Greek epi, meaning above or upon — refers to chemical modifications that control how genes are expressed without altering the underlying sequence. The most studied of these is DNA methylation: the attachment of small chemical tags to specific points along the genome that can effectively silence or amplify particular genes. Think of DNA as the complete script of a play. Methylation is the director's annotation — this scene cut, this line emphasised, this character given more weight. The words don't change. The performance does.

What makes this genuinely startling is that these annotations are not always wiped clean between generations. Some — not all, not predictably, but some — are passed from parent to child, and sometimes grandchild. The environment your parents and grandparents lived in, the food they ate, the stresses they experienced, may have left marks on their genome's expression that you are now carrying.

This is a young science, and it would be a mistake to overstate the certainty of what we know. Transgenerational epigenetic inheritance in humans is real but not yet fully mapped. The mechanisms are still being worked out. But the human evidence, where we have it, is striking.

A grandfather's winter, a grandmother's hunger

The Swedish village of Överkalix sits above the Arctic Circle, remote enough that in the nineteenth century, its harvests were essentially its fate. A bad growing season meant hunger. A good one meant plenty. And crucially for science, Swedish record-keepers were meticulous. Researchers in the late 1990s realised they were sitting on something extraordinary: detailed historical records of food supply across multiple generations, cross-referenced with the health and mortality records of descendants who could be tracked. A natural experiment, preserved in parish registers.

What they found was unsettling in the most interesting way. The food supply available to a man during his slow growth period — roughly ages nine to twelve, just before puberty — predicted the cardiovascular and diabetes mortality of his grandsons. Not his children. His grandchildren. When researchers re-examined the data, they found a parallel effect running through the paternal grandmother to her granddaughters. The transmission appeared to follow the sex chromosomes — information passed from grandfather through his Y chromosome to grandsons, from grandmother through her X chromosome to granddaughters. Notably, the biggest effect of food supply in grandmothers occurred not in childhood but when she herself was a fetus and infant — suggesting that information is being captured at key stages of egg and sperm formation, long before anyone has made a conscious dietary choice. All of this ran through the paternal line in ways that ruled out simple in-utero explanations. Something was being transmitted across generations through a mechanism that wasn't the DNA sequence itself.

The Dutch Hunger Winter offers a different but complementary picture. In the winter of 1944–45, a Nazi blockade cut food supplies to the occupied western Netherlands. For several months, civilians survived on as little as 400–800 calories per day. It was a catastrophe. It was also, from an epidemiological standpoint, a precisely bounded event — a known population, a known period of famine, a known end date when Allied liberation restored food supplies — that allowed researchers to study its effects with unusual clarity.

Children conceived or gestating during the famine were followed for decades. They showed elevated rates of obesity, diabetes, schizophrenia, and cardiovascular disease compared to siblings conceived outside the famine window. That alone was disturbing enough. But the effects didn't stop with them. Their children — the grandchildren of the famine — also showed altered metabolic profiles. The hungry winter of 1944 was leaving biological traces in people born thirty years later who had never experienced a day of food insecurity in their lives.

Both studies point toward the same uncomfortable conclusion: what your ancestors ate — and didn't eat — is not merely history. It may be physiology.

The wisdom we forgot we had

There is a temptation, at this point in the story, to despair. If three or four generations of industrial eating have left epigenetic marks on contemporary bodies, if we are carrying the biological legacy of white bread and tinned goods and the severing of traditional food relationships, what exactly are we supposed to do about it?

But here is where Price's travels offer something more than a warning. They offer a template — not of specific foods, but of a way of knowing food that modern nutrition science is only now beginning to rediscover.

Consider nixtamalization. For thousands of years, Mesoamerican peoples prepared corn by soaking and cooking it in an alkaline solution — typically water mixed with lime or wood ash. The process was laborious and added a step that might seem unnecessary. Nobody had a biochemistry degree. Nobody knew that corn is deficient in niacin in a form the human body can absorb, or that the alkaline treatment breaks the bonds that lock the niacin away, or that it also improves the amino acid profile and increases calcium content. They knew none of this. They simply knew, encoded across generations of practice, that corn prepared this way kept people healthy. Corn prepared without it did not.

When European colonisers adopted corn as a staple crop without adopting the preparation method, the result was pellagra — a devastating niacin deficiency disease causing dementia, dermatitis, diarrhoea, and death. It swept through parts of Europe and the American South for centuries. The knowledge of how to eat corn safely had been sitting in Mesoamerican culture all along. It simply wasn't recognised as knowledge, because it wasn't written in the language of chemistry.

Sourdough tells a similar story. Traditional bread fermentation, using wild yeasts and lactobacilli over a slow rise, substantially reduces phytic acid — an antinutrient present in grains that binds minerals and inhibits their absorption. It also begins to break down gluten, lowers the glycaemic response, and produces organic acids that improve gut health. A slow sourdough loaf made with stone-ground flour and a long ferment is a fundamentally different food from a supermarket loaf made with commercial yeast and produced in hours. Traditional bakers didn't know the biochemistry. They knew the method. They knew it worked. And they passed it on.

Price found this pattern everywhere he looked. The Inuit who ate the organs and skin of their prey — parts that happen to be densely concentrated in fat-soluble vitamins largely absent from muscle meat alone. The African pastoralists who drank fermented milk rather than fresh, making its nutrients more bioavailable. The communities that prized fish eggs, liver, and marrow — foods so nutrient-dense that Price found they were specifically given to pregnant women and growing children, the members of the community with the highest nutritional demands. Nobody had run a clinical trial. The knowledge had been arrived at through millennia of lived experience, refined by the brutal efficiency of natural selection, and encoded in cultural practice. It was nutritional wisdom wearing the clothes of tradition.

Nutrition science, by contrast, is barely a hundred years old. And it has spent much of that century in a reductionist mode — isolating single compounds, testing them in isolation, drawing conclusions that often fail to replicate because food is not a single compound. It is a system of thousands of interacting molecules, many of which we have not yet identified, whose effects depend on what they are eaten with, how the food was prepared, what the gut microbiome of the person eating it looks like. We are, in this sense, still catching up to what Weston Price documented in the 1930s. We now know what Activator X is. We still don't fully understand everything it does.

What we're carrying, what we might reclaim

We are, most of us in the Western world, three or four generations into an experiment in eating that has no historical precedent. The ultra-processed food that now accounts for more than half of calories consumed in many Western countries is not simply a different version of what humans have always eaten. It is a category of food with no analogue in evolutionary history — engineered for palatability, stripped of the compounds that make food nutritious, stabilised for shelf life in ways that alter its fundamental biological character. Pottenger's cats deteriorated over three generations on a diet of cooked scraps. We are running a version of that experiment on ourselves, at civilisational scale, and the Dutch Hunger Winter data suggests the results may already be written into the biology of people not yet born.

This is not a counsel of despair. Pottenger's cats, returned to their natural diet, began to recover. The epigenetic marks left by famine and poor nutrition are not permanent mutations — they are regulatory annotations, and the emerging science of epigenetic modification suggests they can, at least in part, be changed. What we eat affects not just our own methylation patterns but potentially those we pass on. The choices we make about food are not only personal health decisions. They may be, in a very literal biological sense, gifts or debts we leave to people who do not yet exist.

What this asks of us is less a specific diet than a different relationship with food. Not a return to any one traditional eating pattern — Price found no single optimal diet, and that was the point — but a recovery of some of the underlying principles that all those varied diets shared. Food that is real, in the sense of being recognisable to the organisms that produced it. Food prepared with methods that unlock its nutrition rather than strip it. Food understood not as a delivery mechanism for isolated nutrients but as a complex system that humans and their microbiomes co-evolved with over hundreds of thousands of years.

The knowledge of how to eat well was not always contained in books or studies. For most of human history it was contained in culture — in recipes passed down through families, in fermentation traditions, in the instinct to give pregnant women the most nutrient-dense food available, in the understanding, arrived at without science and proven over millennia, that how you prepare food matters as much as what food you choose. We have, in the space of a few generations, lost much of that accumulated intelligence. The question that Price's photographs, Pottenger's cats, and the parish records of an Arctic Swedish village all seem to be asking, in their different ways, is a simple one.

Can we find our way back to it?