Only One Ingredient

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Popular British supermarket, M&S, launched an eye-catching new product range.

Breakfast cereal, with one to six ingredients, listed plainly on the package.

It's created to compete against the high UPF alternatives¹.

Yet, I think this cereal range will succeed for entirely different reasons.

Show your costs

In 2020, Harvard researchers² tested the effects of showing a product's costs.

Rather than just listing the price, they showed ingredient cost (and profit margin).

For the test, this sign was displayed in the university canteen. Real-world sales were measured immediately after the students saw the sign.

Students were 21% more likely to buy the soup when the costs were shown.

Even the profit margin didn't put them off.

Wallets sold with a profit margin of 55% still saw a boost in sales.

Show your ingredients

The Harvard researchers concluded² that showing costs boosts trust.

And that boost in trust makes consumers more likely to buy.

I reckon the M&S cereal will do the same.

In a famously unhealthy category³ where products often contain dozens of unfamiliar ingredients, the "Only" cereal will stand out and garner trust.

And compared to other launches in this highly competitive space, I'd gamble that the cereal should see ~21% more sales.

What do you think? — Phill

¹van Tulleken, C. (2023). Ultra-processed people: The science behind food that isn’t food. W.W. Norton & Company.

²Mohan, B., Buell, R. W., & John, L. K. (2020). Lifting the veil: The benefits of cost transparency. Marketing Science, 39(6), 1105–1121.

³BBC News. (2010, April 19). Many cereals ‘have more sugar than desserts’. BBC News. http://news.bbc.co.uk/2/hi/health/8630446.stm

As a behavioural science practitioner, I believe in the peak-end rule*

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