What is bird flu, and should you be worried about it?

In January, the first person in the US died from bird flu. Learn what the symptoms are and how you can stay safe

The Age of Diagnosis by Suzanne O’Sullivan review – are we really getting sicker?

A neurologist discusses the dangers of overdiagnosing conditions from Lyme disease to ADHD in an era where technology meets pathology

Is apple cider vinegar actually good for you?

People have sworn by the health benefits of apple cider vinegar for millennia. But what does the science say?

Crap jobs, fewer homes, less money, toxic politics. And peak happiness eludes the young: who knew?

Given recent history and the state of the world now, perhaps the thing that makes older people happiest is not being under 45, says Guardian columnist Zoe Williams

Bacterial vaginosis can be passed to women by men, researchers find

Study suggests infection is sexually transmitted and opens up new way to reduce recurrence by treating male partners

Wooden spoons are making us sick? I thought that was fish slices

Another day, another health scare. I’m struggling to know which dangers I should take seriously, writes Arwa Mahdawi

Social media’s gut feeling is all wrong: there is no fast track to a healthy microbiome

A diet high in fibre from different food sources is far more effective for maintaining a healthy gut than supplements and online fads, experts say

Do you know your ‘penis age’? Bryan Johnson does

The 47-year-old tech millionaire claims to have the penis of a 22-year-old. How does he know, and what does it have to do with his dream of living for ever?

Going to the gym gives me so much more than the physique I want, even if body dysmorphia lingers

I feel more focused and energetic than ever before. But as I have changed, so has my algorithm

The one change that worked: ditching ultra-processed foods made me feel healthier and happier

After being diagnosed with a chronic digestive disorder, I cut out junk food and ready meals. Now, my diet is full of fruit and veg – and I’ve got my mojo back