‘Traceability is vital’: labs test thousands of unregulated substances amid peptide craze

Experts warn consumers of unknown risks as one lab says about a third of samples fail basic quality checks

My teenage daughter’s OCD keeps getting worse. What can I do?

Cognitive behavioural therapy may help her to cope with her anxiety and learn that she doesn’t need to respond to intrusive thoughts

What are peptides, are they safe and is there evidence to back up the hype?

Influencers and athletes are among those claiming substances can help with injury repair, weight loss and angi-ageing

Medicines watchdog to investigate UK peptide clinics over health claims

Exclusive: Guardian investigation finds several clinics making potentially unlawful claims about benefits of unregulated therapies

Positive thinking helps you age better? That’s the worst thing I’ve heard all month

If you’re the glass-half-full type, you should be overjoyed at the news coming out of Yale School of Public Health. But pessimists like me? We’re stuffed, writes Emma Beddington

Is it true that … you can never eat too much fibre?

Fibremaxxing is everywhere, and most of us should eat more roughage, but your gut won’t thank you for overloading

Full network of clitoral nerves mapped out for first time

Anatomy of one of least studied human organs could improve outcomes for women who have pelvic surgery

‘I thought, what the hell have I done?’: the people who moved abroad for love – and regretted it

Emigrating to be with your partner sounds wildly romantic, but what happens when the person is right and the place very much isn’t?

I tried HigherDose’s $1,400 PEMF mat to help me relax. I got weird dreams and disappointment

This pricey infrared therapy mat claims to help mood, sleep and muscle recovery. It felt more like a glorified heating pad

Marriage over, €100,000 down the drain: the AI users whose lives were wrecked by delusion

One minute, Dennis Biesma was playing with a chatbot; the next, he was convinced his sentient friend would make him a fortune. He’s just one of many people who lost control after an AI encounter