As American actress Jada Pinkett Smith and her husband Will Smith found, it's not easy staging a food intervention with your child.
"Eat your greens!" has long been the battle cry of parents of teenagers everywhere. But it appears to be a little less necessary for the current generation: the number of vegans in the UK has risen by 350 per cent in the past decade, with young people driving the boom. Almost half of the UK's 540,000 vegans are aged between 15 and 34.
Vocal vegans include 16-year-old climate activist Greta Thunberg, who has spoken about convincing her parents to go vegan ("I made them feel so guilty," she told an interviewer. "My dad is [now] vegan, my mum, she tries, she's 90 per cent vegan"), as well as teen favourite Ariana Grande.
However, going vegan is not without its issues. This week, the American actress Jada Pinkett Smith admitted she and actor husband Will Smith had to stage a 'vegan-intervention' for their 21-year-old son Jaden. "Will and I had a bit of an intervention with Jaden because he's a vegan now, but we realised he wasn't getting enough protein," she said on her Facebook Watch series, Red Table Talk.
"He was wasting away," she continued. "He just looked drained, he was just depleted. He wasn't getting the nutrients." Will added: "He had the dark circles under his eyes, there was even a little grayness to his skin. And we got really nervous."
Jaden, who has since switched from veganism to vegetarianism in the past year, said: "I was just eating, like two meals a day. And maybe one." He also revealed the night before he was due to attend the Californian music festival Coachella he became unwell, due to his vegan diet: "I was not doing good. I wasn't looking good, I wasn't feeling good, I wasn't sleeping," he explained, before admitting he was eventually admitted to hospital with nausea and dizziness.
"We all have issues with food in this family," said Jada, who has encouraged other families to pay attention to their children's eating habits.
After all, can veganism, like clean eating before it, run the risk of being used as a mask for disordered or restricted eating?
"While vegan diets can be healthy, they can also be very badly followed, especially by teenagers and young people," says dietitian Helen Bond, who is a spokesperson for the British Dietetic Association.
Health reasons aside, young people are also increasingly going vegan for ethical and environmental reasons, as is the case with Greta Thunburg. "A young person who becomes passionate about animal welfare or the environment will find plenty of material on YouTube to further convince them," says Bond. "However, without professional advice, this interest in a genuinely worthwhile cause can lead to restrictive eating.
"While I wouldn't advise against a teenager going vegan, I would flag up to parents that the teenage years are peak bone-growing years. This is particularly true for girls. The latest figures from the government's National Diet and Nutrition Survey show that 22 per cent of teenage girls are calcium deficient, compared to 11 per cent of teenage boys. Your calcium needs are greater than ever as a teenager.
"So if you remove dairy you'll fall further short on calcium. There are plant based alternatives of course, like oat milk, that are often fortified with calcium and vitamin D, which helps the absorption of calcium."
Bond also points out that teenagers, especially menstruating girls, need to ensure they're getting enough iodine and iron and says the latest studies also show 54 per cent of teenage girls have low intakes of iron. "If they're not making up for a lack of iron-rich meat in their diet with supplements or vegan alternatives, they may suffer from fatigue, light-headedness, brittle nails and headaches," she says.
And then of course there's the murkier issue of disordered eating: "We know that teenagers and young people get a lot of their nutritional advice from social media," says Bond. "If a young person, curious about veganism, strays onto Instagram or YouTube, they'll quickly be led down a rabbit hole where so-called Insta-gurus, who have little authority on nutrition, will offer advice that could be hugely damaging to a growing child's body.
"Sometimes, people with eating disorders can use veganism as an excuse to eat only vegetables or fruit," says vegan Flic Everett, Managing Editor of Vegan Living magazine. "This is in no way a healthy approach, and it's crucial that parents keep an eye on what teenagers are eating at mealtimes: toast or porridge and nut milk for breakfast is fine, a handful of blueberries isn't."
So what can concerned parents do, whether their child is a teenager still living at home, a teenager living away from home at university, or a 20-something, as is the case with Jaden Smith?
"It's essential that teenagers get enough vitamins and omega 3 and 6," says Everett. "B12 can also be lacking in a vegan diet, so they must eat a balanced range of foods, including plenty of protein such as tofu, pulses and seitan (made with vital wheat gluten). Stock up on frozen protein - most supermarkets now sell vegan Quorn and meat substitutes and they're handy to have, plus lots of nuts and seeds.
"If a parent doesn't know much about vegan nutrition, I strongly recommend they look at the Vegan Society website, or buy a book on the subject to help. I'd suggest sitting down to investigate the nutritional aspects of veganism together and work out a shopping list. The more involved you are, the more likely your child is to have a healthy diet, and avoid health problems. It also makes it easier to convince them you know what you're talking about. A vegan diet isn't automatically a healthy diet, so the more you know, the better placed you are to buy the right foods."