Against a backdrop of government inertia, it was left to an unlikely contender to claim a world-first for transparent reporting on nutritional health.

Nestlé, whose lineup includes an array of well-known chocolate bars, cereals and ice creams – and most recently, a Kit Kat cereal – this week became the first fmcg giant to give a breakdown of the health credentials of its global portfolio.

Having been targeted by campaign groups such as ShareAction – an organisation that also has the likes of Unilever and Tesco in its sights – Nestlé says it wants to set “new standard” for openness.

It’s also promised to come up with a set of new targets to reduce the levels of fat, salt and sugar in its products by the end of the year.

However, Nestlé’s journey shows just what a minefield this area is going to be, for companies and consumers alike.

One of the big problems is the lack of recognised reporting standard. Until that changes, any new reporting is in danger of pouring fog on dry ice for befuddled shoppers.

Let’s look at Nestlé’s claims. It says almost 60% of its products globally are non-HFSS. That excludes petfood, but includes specialist child and medical nutrition products, without which the figure is 37%.

Already, it’s getting muddy. But there’s more.

The above figures are based on a star system used in Australia and New Zealand. When using the UK’s nutrient profiling model – the one used to determine what falls under HFSS restrictions – the figure appears better. That would mean 42% of Nestlé’s products are non HFSS and 27% are HFSS, we are told.

But that includes specialised nutrition and other products such as coffee machines. Looking at just day-to-day food, nearly 40% of lines fall into the HFSS category.

And as if the poor consumer was not already in enough of a spin, those measurements are completely different to the front-of-pack traffic light system, which has been accused of creating confusion in itself.

Yet Nestlé’s system is an absolute piece of cake compared with that of its rival Unilever, which released its own “ground-breaking” transparency figures in October.

Here, it’s best to let Unilever give the explanation. “In this compensatory approach, the overall healthiness of a product is determined by an algorithm that incentivises the inclusion of more healthy nutrients, because they help to ‘compensate’ for the presence of ‘nutrients to limit’ in the product’s final score,” it says.

“Under this model, the product’s ingredients and nutrients are assessed per 100g or 100ml of the product.”

We are then told the scoring uses a combination of different scoring systems: a “binary ‘HFSS’ or ‘non-HFSS’ classification”, Nutri-Score, the EU based A-E system, the aforementioned HSR and the Healthy Choice Symbol, used in Singapore.

If people thought traffic lights were difficult to understand, try getting your head around that.

Joking aside, these are positive moves. While it’s easy to bash the likes of Unilever and Nestlé, these are the very companies that will drive change eventually.

But for transparent reporting to be a game-changer, we need common metrics that cut through to the consumer – and ones that you don’t need a degree in mathematics to understand.