Writer Kirsten Jones gave the test a try…

‘As a fairly healthy 30-something female, I wasn’t expecting any surprises from my blood test. In fact, it turns out I’m actually one of the most fighting-fit humans the lab has tested. Once I get over the shock of my results, Dr Van De Bossche talks me through the details.

“This is one of the best blood results I’ve ever seen – there aren’t many people like you,” he says. “Your fertility hormones, iron levels, thyroid and liver function are top-notch. Only one thing stood out. You have low vitamin D, which is very common in the UK, even in the summer.”

Nothing new there, as a milky Brit who spends five days a week in front of a computer screen. Supplements to the rescue!

“Whatever you’re doing, keep doing it. You’re in the top 1% and I’m jealous. Your renal function is excellent,” he adds. “Anything above 60 is normal and you’ve got 111!”

But it’s important to note a healthy 50-year-old might have different result to mine – and that’s OK. “These figures can drop as you age, it’s all part of getting older and we take this into account,” explains Dr Van De

Bossche.