If you’ve ever looked into the eyes of a primate and had them lift their chin to acknowledge your presence in a kind of ‘alright mate’ manner, you might feel the same way I do about them.

We share 97% of our DNA with some of these animals, and one in particular is in dire need of our help. It is no exaggeration to say the future of the orangutan, one of our closest kin, is in our hands. Or, rather, in our trolleys. Many common food and hygiene products contain an ingredient that relies on an industry conservationists say is killing orangutans: palm oil. It’s the cheapest source of vegetable oil, and one that is rarely described as such on product labels. Derived from fruit grown on palm trees, it’s an extremely efficient source of vegetable oil and the industry’s rapid expansion threatens some of the planet’s most important and sensitive habitats. It’s the most widely consumed vegetable oil on the planet, in about half of all packaged products sold in supermarkets, and one of the most unsustainable industries on earth.

Visiting Borneo on a Malaysian food research trip, I find the plight of this vast island’s most famous animal at the forefront of my mind. It is 30 years since I was last here, and much has changed. At the time of my first visit, Borneo was covered in one of the most pristine (and densest) primary rainforests in the world, and home to the British Army Jungle Warfare Training School.

Many common food and hygiene products contain palm oil – the ingredient many say is killing orangutan

But there’s now another kind of school here: the Sepilok Orangutang Rehabilitation Centre, which rescues and cares for baby orangutans taken from their mothers to be illegally sold as pets, and teaches them how to survive in the wild. It also takes in adults that have spent their entire lives in captivity, chained up or imprisoned in tiny cages, and comes to the aid of orangutans left stranded when their forest home is destroyed, translocating these vulnerable animals to safe areas of protected forest.

It’s ambitious, and they are committed to rescuing and rehabilitating as many orangutans as possible and giving them a second chance to live in their natural environment. Any adult animals that can no longer survive in the wild are given a permanent home there. It’s at the centre I come face to face with Benni and Caspar who, after a few seconds’ appraisal, decide I’m alright, and nod accordingly.

Since my first visit, palm oil has become a go-to ingredient in supermarket goods, and because palm trees grow really well in tropical climates, consumer demand is causing mass deforestation around the world – particularly so in Borneo. The uncontrolled clearing of these forests for palm oil plantations has led to widespread loss of these richly biodiverse and irreplaceable primary rainforests, the natural habitat of the orangutan.

The population of this primate has declined by 50% since I was last here, and as many as 50,000 orangutans have died because of deforestation. Every day, on average, we lose another 25 of these amazing apes. The orangutans, displaced as the rainforests are burned, and at times killed by workers who see them as a nuisance in the logging process, are not the only victims of the palm oil trade: the plantations are also linked to the destruction of habitat of many recognisable endangered species, including tigers, elephants, and rhinos.

On average we lose another 25 of these amazing apes every day

But that’s not the whole story: these forests are home to over 200 known species of mammal, 400 known species of bird, and more than 500 known species of butterfly. They contain nearly 10,000 plant species, including 1,000 orchids, many of which cannot be found anywhere else in the world. And should none of this concern you – because, let’s face it, out of sight, out of mind – one other important function these rainforests perform is to oxygenate our planet. Even here in London we will feel the effect of their loss one day: our planet’s very lungs are being systematically destroyed.

Avoiding it, however, is a tricky business. Most of the time it’s totally unnecessary, but it’s cheap, and food manufacturers use it as a bulking agent, so it’s hard to find alternative products that don’t contain it. Common items that could contain palm oil include ice cream, chocolate, bread and pizzas, crisps, instant noodles, margarine, vegan cheeses, soap, shampoo and cosmetics (including make-up and fake tan). To compound the problem, palm oil byproducts are now finding their way into animal feed, which means if you’re an omnivore that shops carefully, even some meat may have contributed to the problem.

Believing truly sustainable palm oil to be impossible, many organisations in the EU, US and Australia now advocate avoiding it altogether, though India and China each consume more palm oil than the EU, and a 30% increase in production is projected by 2020. Indonesia has just increased subsidies to boost palm oil production for biofuel.

Boycotts could also push companies to use other oils instead, which could cause even more damage – palms produce far more oil per acre than other vegetable-oil plants. And possible ‘synthetic biology’ substitutes are another minefield entirely.

Sustainability is a huge conundrum, but my conscience informs my shopping, and I’ll continue to avoid palm oil in all its guises (yes, even make-up and fake tan) until someone much smarter than me comes up with an answer. Hopefully before we eradicate orangutans from the wild forever.

Want to read more from Richard H Turner? Catch up on the rest of his columns.