Sainsbury's has announced it will stop selling brown eggs in favour of white eggs, citing a lower carbon footprint. The move has prompted many Brits to question whether there is any nutritional difference between the two varieties and which one is actually better.
Environmental Impact of Egg Colour
The reason behind Sainsbury's switch to white eggs is their supposed 12.7% reduced carbon footprint compared with brown eggs, based on the chain's own research. This is because hens that produce white eggs require less feed while laying the same number of eggs, reducing resources throughout the supply chain. Feed production represents 50-60% of the environmental impact of egg farming.
Britain consumes approximately 14.5 billion eggs annually, generating an estimated 4.35 million tonnes of carbon dioxide emissions during the process. If the whole industry achieved the same 12.7% reduction cited by Sainsbury's, emissions could drop by over 550,000 tonnes of CO2 each year, according to The Independent. That is roughly equivalent to taking nearly 300,000 cars off Britain's roads, reports the Express.
History of Egg Colour Preference
For most of the 20th century, white eggs were standard in the UK. However, during the 1970s, brown eggs became the preference of Britain's middle class and ultimately dominated the market. Today, most eggs purchased are brown, and many consumers assume the darker the egg and the more vibrant the yolk, the superior the quality.
Yolk Colour and Nutrition Myths
In truth, there is minimal difference between the two coloured eggs. Influencer Sunna Van Kampen, known as @tonichealth, suggested in a TikTok post that distinctive vibrant orange yolks are not an indicator of quality but instead a consequence of what the chickens have been fed. Sunna, who has 8.5 million likes on the platform, said: "The reason why your yolks are so dark and orange... is because they feed [the hens] marigold and paprika."
This was verified by a 2024 study published by the National Library of Medicine. "We found that paprika improved the color of the egg yolks and affected the hens' blood cholesterol levels in different ways," the study claims.
No Nutritional Difference
The shade of a yolk is mainly determined by pigments known as carotenoids, which occur naturally in ingredients like maize, marigold, peppers and carrots. The shade of the egg shell depends on the breed of the hen. Generally, white hens lay white eggs and brown hens lay brown eggs.
There is no nutritional difference between white and brown shelled eggs, according to British Lion Eggs. What is far more significant is examining the code stamped on the shell. Organic eggs carry a 0, free-range eggs a 1, barn eggs a 2 and eggs from caged hens a 3 — though all major supermarkets no longer stock caged hen eggs.
So, neither the shell nor the yolk colour indicates how healthy the hen was or whether the egg will produce a better omelette. What it does reveal is that stocking white eggs is considerably more cost-effective for a supermarket chain like Sainsbury's, and possibly slightly more environmentally friendly.
