Scientific fake news is more popular than ever: the flat Earth theory, anti-vampire mists and healing hydrogen-peroxide drops are just a click away.

Dr Giles Yeo knows it all too well – as a researcher, a TV personality (Trust Me, I’m a Doctor; Who are you calling fat?; Vitamin Pills - Miracle or Myth) and popular author (Gene Eating), he actively engages larger audiences to fight against pseudoscience. Off-screen, he is a Wolfson Fellow and Scientific Director of Genomics/Transcriptomics Core at the Wellcome - MRC Institute of Metabolic Science, studying obesity.

He links the proliferation of fake news to the birth of social media: “In the past, the likelihood that you would find someone who believes what you believe was low, so you kept all those thoughts in your head. I don’t think people changed that much, but I do think social media has enabled spreading fake news.” However, this is just part of the truth, as pseudoscience has also begun to take centre stage in mainstream media. A recent example is Gwyneth Paltrow’s The Goop Lab, released on Netflix this month, which explores a range of alternative and pseudo-medicinal cures – from advising how you can control your energy field to discussing the benefits of magic mushrooms.

“The only way we can fight this degradation of truth is standing up, telling the truth...”

At the mention of it, Yeo gets passionate: “It’s huge! Enormous! Hundreds of millions of people. I’m amazed they gave her the platform. I do think that we, academics, have some role to play in it in terms of not communicating to non-experts what we actually do and how scientific method works.” According to Yeo, the public see scientists as a bunch of people constantly changing their minds. What non-experts cannot see is that arguing with each other is the researchers’ job.

“I know lots of colleagues of mine who think that public engagement is a waste of time,” touching on a particular nerve in his field. “But I don’t think so. It is rather our duty for a number of reasons.” Yeo claims that the low number of people reading scientific papers calls for popular explanation. Secondly, he fears that if scientists themselves do not communicate, then someone that is less of an expert will do so in a poorer way. “And then who are we to complain?” he asks conclusively.

Yeo advises that all scientists should engage as the opportunity arises. “Everyone can do it to different degrees using different methods: writing, TV, going to the primary school, presenting at the science festival. The only way we can fight this degradation of truth is standing up, telling the truth and pointing out when people are talking bullshit.”

The problem is that it takes time. “I study obesity, other people study cancer, but there are people with cancer, with obesity, with any other disease, and they want to be cured now. So there is this vacuum of people looking for answers, and things like Goop fill the space,” Yeo says, pointing out that the increase of bizarre pseudo-science cures is a natural response to a society demanding instant results.

He does concede that there can be a humorous element to some scientific fake news, no matter how exasperating they may be to trained experts. “Like Goop and their jade eggs. Do whatever you want with the jade egg.” Yeo shrugs his shoulders. Yet, in some situations, it becomes dangerous. Yeo’s classic example is the anti-vaccine movement. “You can sell all kinds of lotions and potions, if all that people are doing is wasting their money. But when people are actually dying or harming themselves, it is a problem.”

“I don’t think people changed that much, but I do think social media has enabled spreading fake news.”

When it comes to diets, there is a similar dilemma of fake news. “The tip of the iceberg is, for example, Robert Young’s alkaline diet.” Young believes that, since our blood is slightly alkaline, we must therefore eat alkaline foods in order to stay healthier. However, from a scientific perspective his argument is completely wrong; it dismisses that our acidic stomach acts like a barrier, and his classification of what alkaline is makes no sense. As an example, Young considers a lemon, which is full of acids, as alkaline.

But, despite all the scientific criticism, the alkaline diet does, in fact, work for a lot of people. Why? “Because it is very close to being vegan: very low on meat and dairy products,” Yeo explains. “So people eat it, lose weight and get healthier, because as you lose weight, you lose the risk of different diseases.”

Yeo is hesitant when being asked if veganism is a healthier way of life: “If you are doing it properly, it’s fine, but you shouldn’t impose your diet on other people.”

He becomes even more reluctant when I ask about vegan children. He answers slowly and considerately: “Personally, I believe that children should be given the best food possible. Including meat, milk and eggs and everything, then allow to make their decision once they passed the rapidly growing phase. Veganism, unless you are very careful with it, is not a great idea for kids.”

The elephant is still in the room: what’s the harm in meal plans like the alkaline diet, when it seems to be working? Yeo expects the question: “The problem is when you start taking things to the extreme. Like Robert Young did.”

Yeo explains this harmful chain of mistaken arguments: “First, Young thought that acids were bad, therefore diseases must be acidic, and since cancer produces a lot of lactic acid, therefore cancers are acidic. So he suggests infusing sodium-bicarb into the blood to neutralise the acid. I am not even kidding you. He started a clinic in California to cure cancer, by telling people to come off their chemo.” Therefore, it works as a kind of a gateway drug: via pseudoscience, you can get from arguing about eating more vegetables to giving up cancer treatment.

Yeo thinks that fixing our diet is necessary for a healthy life, but eating foods like turmeric, ginger or garlic will not cure the disease. Yet what ‘health’ and ‘obesity’ means is different in each individual case. “In a population you can be fat in many sizes, but for the individual there is no health at every size. Someone who is bigger can be far healthier than a skinny one. The trick is trying to identify where that line is where you become ill. Health is not an SI unit,” he summarises.

Thinking about body positivity versus fat shaming, Yeo prefers to differentiate between pointing out the problem of carrying too much fat and blaming the person for the problem. “I think that we as a society, should take those two things apart. I understand the body positivity movement, because people with obesity have been judged and called out all over their life, so they react. But we also have to understand the science underlying it: if you do carry too much fat exceeding your limits, it is unhealthy for you.”

He also warns us that the beach-body ideal does not correspond to the health requirements. “Losing weight for health very seldom coincides with how you look. So it is unlikely to end up looking like Gwyneth Paltrow when you look in the mirror [even] after a diet to get healthier.”

After catching a few minutes of The Goop Lab, Yeo’s disagreement that body size can automatically indicate health is a comforting thought.