Ultra-Processed People by Chris van Tulleken — how our food turned to junk

On Monday, the World Health Organization issued new guidelines advising non-diabetic consumers against using non-sugar sweeteners to control weight. Its top nutritionist declared: “NSS are not essential dietary factors and have no nutritional value.” Yet incarnations of NSS, such as aspartame, sucralose and stevia, can be found sprinkled throughout common foods and drinks, especially low-fat versions that purport to benefit health.

The announcement will not surprise Chris van Tulleken, a London-based podcaster, television presenter and infectious disease doctor. In Ultra-Processed People, a fearless investigation into how we have become hooked on ultra-processed food, or UPF, van Tulleken identifies sweeteners as just one component of a modern nutritional landscape in which “most of our calories come from food products containing novel, synthetic molecules, never found in nature”. We are no longer eating food, one academic memorably tells him, but “industrially produced edible substance”. Those substances are formed using a mix of cheap ingredients, machine processing and synthetic additives such as stabilisers and flavourings.

So prolific are these foods that, in industrialised countries such as the UK, the average person ingests 8kg of additives a year, four times the weight of flour we buy annually for home baking. Yet, it is not so much the additives themselves that are the problem but the diets associated with them. Tragically, van Tulleken writes, echoing food campaigner Henry Dimbleby’s recent book Ravenous, those modern diets are proving harmful: for waistlines, for teeth, for gut microbiomes and for the environment.

His key message will have you scurrying to your cupboards: if an ingredient on a food packet isn’t one you would normally use in a home kitchen, it’s UPF. Once you start seeing them — soy lecithin or glucose-fructose syrup, for example — you’ll spy them everywhere. And, if there is any justice, this gripping, well-evidenced exposé will shame policymakers and shake the food industry to its money-driven core.

The age of eating UPF arguably started in 1879, when chemist Constantin Fahlberg experimented with coal tar in an attempt to produce medical compounds. He inadvertently created saccharin, a compound 300 times sweeter than sugar and, thanks to sugar shortages driven by the first world war, the first wholly synthetic compound to be added to the diet on a large scale. There followed a new era of synthetic food chemistry, in which such ingredients helped to make mass-produced food cheaper and more appealing to the palate, as well as longer-lasting and easier to transport.

For cost-conscious, time-poor consumers, these innovations were a godsend. But processed foods, we now know, also seem to drive excessive consumption. If you, like me, have ever wondered how the French stay slim on croissants, butter and wine, the evidence as laid out by van Tulleken seems to suggest it is because they are eating real sugars, real fats and real carbs, that are less processed and that don’t bypass the body’s ability to regulate intake.

Ultra-Processed People, based on a documentary that featured van Tulleken eating a diet consisting of 80 per cent UPF for a month, is more than just a great science book: it breaks down a complex issue of cultural, social, economic and political importance with clarity and sensitivity but without moralising; it competently evaluates the scientific literature; and it roams the globe in search of answers.

It is not crisps and fizzy drinks that make us fat, we are deceived into believing, but our own shortcomings

Importantly, it analyses how we got here, with rising numbers suffering from obesity and diabetes. The food industry — by recruiting compliant scientists, funding studies, pushing clever marketing messages and influencing policy — has been able to cook up a self-serving narrative that shifts the blame for the harm their products cause. It is not crisps and fizzy drinks that make us fat, we are deceived into believing, but our own shortcomings in the form of sedentary lifestyles and feeble willpower.

Nutrition science is dripping with conflicts of interest, whether it is companies pushing infant formula in low-income countries or KFC getting involved with charities working on obesity policy. Industry, van Tulleken rightly believes, should never be at the policy table: “No one thinks that [tobacco company] Philip Morris should fund the doctors who generate the research around whether smoking harms you . . . [or that] tobacco legislation should be written by charities funded by British American Tobacco. Why should food policy around health be any different?”

That culture persists. When the WHO sweetener story dropped this week, I scanned the responses from various scientists. Most approved; one comment stood out as more equivocal. A conflict-of-interest statement showed the scientist had previously worked with the International Sweeteners Association. That’s when I reached for the salt.

Ultra-Processed People: Why Do We All Eat Stuff That Isn’t Food . . . and Why Can’t We Stop? by Chris van Tulleken, Cornerstone Press £22, 384 pages

Anjana Ahuja is a science commentator

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