Guess who might be having quite a busy day today? I’m going to go with the lawyers of protein bar companies whose phones, I imagine, are glowing red. Because Joe Wicks: Licensed to Kill (Channel 4) practically burnt down their houses. It pulled zero punches in claiming that some of the ingredients in these bars, which gym bros buy and parents pop in children’s lunchboxes, can increase the risk of illnesses from blood clots and diarrhoea to cardiovascular disease and cancer. And yet, shockingly, it’s all legal.

Wicks conducted a stunt with Professor Chris van Tulleken in which he made his own protein bar named Killer, which contains ultraprocessed sweeteners and emulsifiers already used in other such products, and which he genuinely planned to sell. On the front it made the usual buzzy health claims about containing 21 vitamins and so on. On the back, however, was a cartoon of a very ill Wicks as it warned that eating could raise the risk of cancer, stroke and early death.

• Joe Wicks: My fight against UPFs and why fat jabs aren’t the answer

This was brave television and not your average health documentary. Despite Wicks and his wife appearing to get cold feet halfway through (although that could have been the compulsory flick of TV faux jeopardy), Van Tulleken said it was important that they went the whole hog by marketing and selling it. He and other scientists have been banging on about the harmful effects of ingredients for ten years (he wrote a book called Ultra-Processed People) and yet nothing changes, he said. After the US, the UK eats more ultraprocessed food (UPF) than anywhere else on earth. Shock tactics are needed to show what kind of stuff people are eating, often under the deceitful guise of “health food”.

I did feel that if you could watch this show and still buy your child a protein bar afterwards you must be mad, so some of these brands will presumably be furious. Van Tulleken said UPF doesn’t even deserve to be called food and is better thought of as an “industrially produced edible substance” with “every single product optimised for max consumption”.

Wicks is a good person to spread the message because he is a very popular, down-to-earth fitness coach, and also because he admits that he likes junk food too. He ate some Hula Hoops and said: “I have not stopped farting”, which we really didn’t need to know.

I have received a press release in which a “legal expert” warns that Wicks could be sued for product disparagement and defamation. Various well-known protein bars with manly names were called out for their ingredients, which I can’t imagine will go down well in the boardrooms. But I imagine Channel 4’s own lawyers aren’t daft, and in any case these ingredients are listed on the packaging.

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Still, the press release warns that regulators such as the Advertising Standards Authority take “a dim view of stunts that mislead consumers”, and if Wicks’s bar was bought and eaten he could face investigations into “product safety and labelling”. It is in the second part of the documentary that we will see how it plays out, but it wasn’t available as a preview so your guess is as good as mine.

Wicks deserves credit for putting his head above the parapet, especially in an age when many influencers are happy to simper while promoting any brand that pays them. It’s all left me feeling quite smug; I’ve always found protein bars inedible.
★★★★☆

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