Letter From China: Fermented Food, Gut Health, and Why We Age So Differently

I came to China to look for better ways to make fermented foods that support gut biology, because gut biology is a key part of the fight against diabetes and similar chronic illness. At first, I thought the trip would be a failure. Then I noticed something I could not ignore: in rural areas there were many people in their eighties and nineties who were still fit, active, and cheerful. This article is a simple story of what I saw, what surprised me, and what it might mean.

Preface: Why I Came to China

I am writing this from China, moving between places and learning as I go. It is not a perfectly planned report. It is a rolling account, written “on the fly”, and I will probably sort it out later. At the time of writing I have been in Shanghai, I am now in Shenzhen, and next I plan to head to Hunan to see what I can learn in more rural areas.

The reason for this trip is practical. I want to improve gut biology, and I am looking for fermented foods that can help. Diabetes has exploded in recent decades, and I am not satisfied with a system that mostly manages symptoms with pills while the root causes keep growing in the background. Food quality, soil biology, and gut biology are part of a deeper answer.

My First Big Mistake

My first goal was to find good “starters” for fermentation. Starters matter because they influence what microbes dominate. I expected to find a wide range of starter cultures used in farm fermentation.

Instead, I found something different. In this part of China, fermented vegetables are extremely common, but many farms do not use starters at all. They use large amounts of salt. It is closer to pickling than what many people in the West call fermentation.

I tasted it and thought: this is terrible. It was bitter, harsh, and not something most Western people would willingly eat. I started thinking the trip might be a dead end.

Then I remembered a lesson I keep learning: the Chinese have been eating many of these foods for centuries. When I ridicule what they do, I often later learn they were right and I was wrong.

The Key Insight: Chinese Food Is About Contrasting Flavours

The message arrived later, after I had already started writing. Chinese food is not designed around a single flavour. It is designed around contrasts. They rarely serve one dish alone. They serve four or five dishes, and sometimes far more at a feast. Each dish has a role in the overall taste experience.

I read an article about strawberries. Most people assume strawberries are sweet because they contain a lot of sugar. Analysis suggests the sugar level is not especially high, but strawberries also contain bitter compounds. The contrast between bitter and sweet can fool the brain into perceiving the taste as sweeter than the sugar content alone would suggest.

This matters. In older times, China did not have easy access to sugar. Honey existed, but it was rare and expensive. Yet people still enjoyed “sweet” tastes. Mixing a small amount of bitter fermented vegetables with other foods can create a sweet impression without large amounts of sugar.

That struck me as important. The health challenge is not only knowing what people should eat. The real challenge is getting people to eat a healthy diet and continue to eat it. The Chinese are masters of making food taste good. This “bitter plus sweet” trick might be one useful tool in reducing sugar while keeping food enjoyable.

Old but Fit and Healthy: How Come?

Now to the other observation that grabbed me. In rural areas I saw many old people, in their eighties and nineties, who were seriously fit. They were doing group exercise and dancing early in the morning, and then working in farms or gardens during the day.

I have been saying “next year I will start to get old” for about fifteen years, but the point stands. I am not frightened of dying. Life is finite. But while I am alive, I want to be fit and healthy so I can enjoy life.

So the question became simple: how can people be so old, yet so healthy?

This is not a formal scientific paper. What I am describing is observational. It is more a chatty story, with a few jokes, and some serious bits. I also have a “thing” about the misuse of statistics, so I am not going to pretend this is proof. It is evidence, and it is worth paying attention to.

Shanghai: A City, and a State

I flew into Shanghai for a basic reason: I needed to renew my Chinese residence permit. Shanghai may not be the best place for fermentation research. Szechuan might be better for spices, and I may go there later. But Shanghai was the entry point.

We often think of China as one country with one character. In reality it is a collection of very different “states”, bound together into one system. Shanghai alone has a population larger than all of Australia. The city is dense, but it also has a wider region that produces food for the urban centre.

That wider ring is where we travelled.

Farmers of Forty Centuries: The Recycling Culture

For roughly four thousand years, Chinese farming has been based on near-total recycling. There is a book titled “Farmers of Forty Centuries” that explains how this worked. Traditional farming systems were built on returning nutrients back to the land, not exporting fertility and replacing it with chemicals.

Modern farming is now entering China fast. Small farms collapse, large corporations take over land, and less sustainable systems appear. Feedlots dump waste into rivers. Young people move to cities. Older people remain behind, sometimes converting houses into guest houses.

On this trip we stayed in a farmer’s house run by an older couple, with their father who was 81. His granddaughter was herself a grandmother, which says something about long working lives and long family timelines.

We ate meals that came from local produce: vegetables grown on the farm, fish from local rivers, and simple cooking. These meals may not have changed much in hundreds of years. Nutritionists rave about the Mediterranean diet, but this traditional rural Chinese diet could be just as valuable.

Yellow Rice Wine and the “Clumsy Enzyme”

I already knew Chinese white rice wine. Honestly, I find it close to drinking nail polish remover. You almost need to pour it straight down your throat without touching the sides, or your lips will vanish.

But our local farmer produced yellow rice wine. It was completely different. Much more mellow, pleasant, and not strong. It came straight from the keg where it was made. Apparently, farmers across China brew versions of this harmless drink.

I did notice one strange side effect. We had barely dented the keg when I spilled my glass all down my front. The obvious scientific explanation is that it contains a “clumsy enzyme”. I may need to do further research in multiple regions to confirm if all yellow rice wine contains this enzyme.

Hard Lives, Healthy Bodies

Living with older rural people also forced me to remember their history. Many were born in the 1930s, through political collapse, invasion, civil war, famine, and the chaos of the early Mao era. During that horrible period, estimates suggest tens of millions died.

I have personal proof of how rough those years were. My wife Xiulan was taken from her home as a teenager and sent by train for days to a cold region. Many from that time have bent fingers from frostbite because they slept two to a bed and the outside hand froze.

Then came Deng Xiaoping, who put pragmatism first and triggered extraordinary modernisation.

So how can people who endured that history still be so active in old age? A nit-picking pseudo-statistician might say the weak were removed and only the strong survived. That ignores what I saw: there are many old and fit Chinese people.

Diet, Gut Biology, and the Problem of Modern Food

Certain facts are hard to avoid. Diseases like diabetes, heart attacks, and strokes have exploded in recent decades. Obesity, which is a visible indicator of metabolic problems, has become normal. The major change is diet: from fresh local foods to highly processed products loaded with sugars, fats, and minimal fibre.

This engineered food tastes good partly because it is designed to create cravings. In plain terms, it is addictive. That is not moral judgement. It is product design.

Gut biology does many things. It helps digest food. It helps create vitamins. It helps release minerals. It also acts like a second brain that influences what we crave and what we seek.

I am not saying that fixing gut biology solves everything. But if gut biology is damaged, resisting cravings becomes brutally hard. People can be told “eat less, exercise more” a thousand times, and still fail, because their internal signals are pushing them toward high-reward food.

That is why I am chasing fermentation. So far I have not hit a jackpot. But China is large, and there are many regions and traditions still to explore.

Variety as a Hidden Strength

One thing that stands out in China is food variety, especially in traditional diets. Markets are full of ingredients I have never seen in Australia. Mushrooms alone come in countless varieties. Fish and vegetables appear in many forms. Meals are built around small amounts of many things, not large amounts of one thing.

It may be that no single ingredient is magic. It may be that variety itself is part of the solution.

Parks and Daily Movement

While waiting on paperwork, I spent time in Shanghai parks. Parks are essential to Chinese city life and make high-rise living workable. They are used in waves: morning for exercise and dance and tai chi, mid-morning for mums and kids, afternoon for older people talking, evening for music and more dancing.

This pattern matters. It is social, regular, and built into daily life. It is not “fitness culture”. It is community movement.

A Silly Space Traveller Story (With a Serious Point)

Sitting in the park, I imagined two space travellers watching Earth. They see factories producing plastic-box food and fizzy drinks, and they wonder if humans are slowly killing themselves on purpose. They debate using “blood clotting rays” or “erectile dysfunction spray”, then conclude humans already have a slow-kill plan: load the planet with cheap sugar and addictive processed food, and wait a hundred years.

It is silly, but there is truth in it. Food processing is the biggest industry in the world. When an industry profits from cravings, the population’s health becomes collateral damage.

China’s Contradictions: Technology, Healthcare, and Leapfrogging

China is full of contradictions. In a farmhouse, meals are cooked on a wood stove, but WiFi is immediate. Dialects change by region. In cities, bikes are shared via phone apps. Electric cars are rented by the hour. Charging points are built into new apartments before electric cars are widespread.

This links to an idea I observed decades ago in engineering software: leapfrogging. Countries without established traditions sometimes adopt new systems faster, because they do not have old habits to protect.

China’s hospital system also surprised me. You can go to a hospital, be assessed, run tests (blood tests, scans), and see a specialist in the same morning. It involves queues, but it is fast. Benefits like speed and access rarely appear properly in economic comparisons, but they are real.

Renewables, Pollution, and Why Governments Act

Shanghai has a pollution problem you can see from the seventeenth floor. Governments do not want 1.4 billion angry people. Massive investment in wind, solar, and batteries may be linked to climate belief, but it is also driven by the immediate need to reduce pollution. China is betting that renewable energy will become cheaper, and that storage will catch up.

This is part of a wider difference in how systems work. Western economic thinking often treats free markets as a kind of religion. China’s system is more controlled, especially in finance, and it can plan on longer time scales.

So What Can I Do?

I cannot fix global politics. I cannot reform the food monolith by shouting at it. What I can do is keep experimenting with growing systems and food systems that improve health, especially gut biology.

If I find a good fermentation method that helps people improve gut biology, the next challenge is distribution. Patents create monopolies, and I do not want to stop people using useful technology. I also do not want large organisations taking it and using marketing power to create a monopoly anyway.

One idea is a global club. Members would pay a modest fee and receive know-how and support on growing systems and gut-biology food methods. Information would be shared on a confidential basis. Members could earn revenue by producing and selling biologically active plants, fermentation “mother stock”, inoculants, and fresh or fermented produce. The goal would be practical adoption, fair benefit, and continuity beyond any one person.

Conclusion

This trip did not deliver the simple “starter mix jackpot” I first hoped for. But it delivered something else: strong observational evidence that traditional diets, variety, daily movement, and social routines can support health and fitness deep into old age.

I am continuing the search. I will keep exploring fermented foods, flavour contrasts that reduce sugar without reducing enjoyment, and systems that make healthy choices easier rather than harder. If you have thoughts on how to promote and share this work in a fair way, I would value your comments.

Colin Austin — © Creative Commons. Reproduction allowed with source acknowledgment; commercial use requires a license.