Not long ago, if you were ill, you'd see a doctor. Now, you go online. There are countless sleek and soothingly medical-looking websites: symptom checkers, diagnostic tests, friendly blogs and podcasts. Want to track your blood sugar? Your heart rate? Your sleep? You can. Need to focus? Want to lose weight fast? Everything is a click away. But who, if anyone, is regulating this? As NHS waiting times grow ever longer, new technologies provide immediate insights into our health. From mental wellbeing influencers promoting untested therapies, to entrepreneurs peddling their own alternative remedies, online health hacks are big business. These self-styled medical experts glow with good health and they guarantee results but they don't own any of us a duty of care, they know nothing of our individual medical history and the usually profit from what they promote.

So why do we trust them?.