Somebody really clucked up a new report about eggs in the UK.

The environmental cost of welfare-driven policy changes in UK egg production is a paper that appeared in Royal Society Open Science on 29 July 2026. And then it was scooped up by The Guardian.

Organic eggs have worse impact on climate than eggs from caged chickens

Hold on a second, that’s a sensational claim. Let’s take an actual look at the paper.

It models eight ways of meeting UK egg demand and wants us to believe that furnished cages carry the lowest environmental impact and need the fewest birds.

Should we believe?

I’m here to tell you that in five places its text contradicts its own charts. All five sit in the section on how many hens each system requires. How did this go to print, let alone spur The Guardian to cluck, cluck about what’s “worse”?

Apparently the shift to fully organic free-range production would need 2.67 million additional laying hens. Against a national flock of 40.44 million, that would be an increase of 6.60 percent. The paper, however, writes just 2.67 percent. The difference of millions of chickens has been printed as a percentage. It happens four times in a single paragraph. A fifth figure in the same paragraph is calculated correctly, so it’s some kind of weird sloppy mistake, which everyone can see plainly.

Each of the four wrong percentages is too small by exactly 2.4728. That number is 100 divided by 40.44. So I believe the same simple wrong calculation was repeated four times over.

The vocabulary also matters, given what happens next. “Furnished cage” is the paper’s term. Defra, the government department that regulates this, calls the same system an “enriched colony cage”.

On 12 January 2026 Defra, acting for the UK, Welsh, Scottish and Northern Ireland governments, opened a consultation proposing a ban from 2027 on installing new enriched colony cages and a ban from 2032 on using existing ones. It closed on 9 March. The responses are still being analysed. Enriched colony cages supply a little over a fifth of UK shell egg production.

Every one of the five drops the paper’s credibility a notch. All together it seems too weird. It wants to argue that cage-free systems need more hens for the same number of eggs. But then three of their five errors weaken that case, while two strengthen it. The mortality error also makes battery cages, banned in the UK since 2012, look better than furnished cages. That’s a clue something is very wrong with their whole setup.

The mistakes do have a pattern. Each wrong figure is a quantity being correctly calculated, and then filed under the wrong heading. 2.67 is the count of extra hens in millions. 0.94 million is total mortality under furnished cages, entered as a saving. 36.72 million is the number of hens slaughtered, entered as the number kept. Every one of them is a bar in Figure 4.

That suggests the pictures were used incorrectly to generate the text. Anyone holding the model divides 2.67 by 40.44 and gets the 6.60. The digits are all there, but they’ve been scrambled.

Supposedly seven authors gave final approval for this math, and agreed to be held accountable. What they approved understates the welfare result the whole argument rests on by a factor of two and a half.

Here are six more things I found while trying to understand why this paper is so bad.

• The inventory comes from Leinonen 2012 and 2014, which is egg production data from around 2009 and 2010. The paper limitations section does not mention this rather critical point. An author mentions it to the Guardian, however.
• Mortality is fixed at 2.50 percent in furnished cages rising to 8.00 percent in organic systems, all of it carried over from the same 2009 and 2010 sources. Reference 30 is Schuck-Paim 2021, covering 6040 commercial flocks and 176 million hens in 16 countries, which found no mortality difference between caged and cage-free housing in recent years. That study covers indoor systems only, so it bears on the barn figure rather than the free-range and organic ones. The paper dismisses it in a subordinate clause and cites it with the wrong volume number.
• Current UK grid emission factors are applied to 2010 energy consumption numbers. That’s wildly out of date. Barn acidification is then attributed to energy use.
• Welfare is only defined as headcount, mortality and slaughter number, which makes no sense. The paper says openly that quality of life was not available to it. That admission gives up the game. Under a fixed output constraint, a metric that counts animals rewards whichever system converts feed fastest. The finding follows from the setup.
• The method comes from Hayek and Garrett 2018 and Chan, Franks and Hayek 2022, both cited. Those authors built the headcount frame to argue that extensive systems cannot scale and consumption must fall. This paper places consumption change out of scope, stealing an instrument and removing the important warning labels.
• Two authors hold commercial affiliations. Two. Margaret Hegwood manages corporate engagement at the Centre for Feed Innovation, a think tank founded in 2024 to advance novel feed ingredients, on a paper finding that feed dominates every impact category. Rhea Harrison is at Foodsteps Ltd, an environmental consulting company that sells life cycle assessments to food businesses and markets its research partnerships as a route to shaping policy. The declaration names Hegwood. That’s only one. And states that the other authors have no competing interest.

The paper page carries a link to its review history. And for this paper, when you click on it, you get this banner instead:

It’s a good day to be a kid in Santa Cruz, California. The city has won a court case rejecting an industry attempt to overturn a public vote.

“This ruling affirms the City’s authority as a charter city to implement a thoughtfully crafted local measure that addresses local health concerns, generates local revenue, and was approved by City of Santa Cruz voters,” said City Attorney Cassie Bronson. “We are pleased with the court’s well-reasoned analysis and appreciate the careful consideration given to the legal issues presented in this case.”

The Sugar-Sweetened Beverage Tax was approved by Santa Cruz voters to generate general revenue for the City, with an eye toward funding services and programs that contribute to community health and wellbeing.

The more harm to citizens, the more money the sugar industry made, which was being spent on doing more harm and blocking safety measures. The sugar industry basically argued that predators could not be regulated by victims. Santa Cruz applied a common sense general revenue tax, with proceeds directed toward services and programs that address the public harms from sugar.

To be clear, the sugar industry wrote state law and then sued the city with it, and lost. In 2018 the beverage industry qualified a statewide ballot initiative requiring two-thirds supermajorities for nearly all new local taxes, then withdrew it in exchange for California lawmakers passing a law to preemptively ban local grocery taxes until 2031, including a provision withholding sales tax revenue from any city imposing one even if a court found the tax valid. A 2023 state appeals court ruling struck this bonkers revenue-withholding provision as unconstitutional, which opened the door for Santa Cruz offering a Measure Z.

The plaintiffs against the city were a national association of sugar drink brands, joined by the California Grocers Association, California Hispanic Chambers of Commerce, California Alliance of Family-Owned Businesses, California Chamber of Commerce, and California Fuels and Convenience Alliance They filed suit in May 2025, after the American Beverage Association had poured almost $2 million into their eat-shit-and-die campaign against a tiny city’s local public health measure.

Yudkin, Professor of Nutrition and Dietetics at the University of London from 1954-1971, published Pure, White and Deadly in 1972 warning of sugar’s role in heart disease and metabolic harm. This is Yudkin’s book Contents from his 1986 edition:

The industry response to silence him is well documented: the Sugar Research Foundation secretly funded deflection research, as exposed in a 2016 JAMA Internal Medicine analysis of internal industry papers. The professional isolation of Yudkin himself is a matter of record in the publication timeline of his own book, out of print for decades before its 2012 reissue.

Santa Cruz voters simply moved in 2025 towards what should have been enacted in 1975.

Well, there goes my steep discount on perfectly fine food. I often get 30% off or more buying “sell by” dairy products. It’s a strike signal for me, yet for others it’s the opposite. Reducing confusion makes sense when you look at the colossal amount of waste it has generated. And my favorite part of this story is the conclusion.

With no federal regulations dictating what information labels should include, the stamps have led to consumer confusion — and nearly 20% of the nation’s food waste, according to the Food and Drug Administration. In California, that’s about 6 million tons of unexpired food that’s tossed in the trash each year.

Nate Rose, a spokesperson for the California Grocers Association, said some grocers have had to overhaul their labeling systems, but as a whole, the association has been supportive of the change.

The new labels will result in “a win-win where we can reduce food waste and consumers will find these decisions a little bit simpler,” he said, adding that shoppers will still find old labels in stores for months to come as grocers sell through the products that already have them.

He is talking about a stamped exact date as if it’s just a vague process that runs for months on its own. That alone exposes the complete mess of “sell by” label management.