Can your noisy knees predict the future?

Our joints are capable of making a cacophony of sounds, even more so as we get older. Is it ever a cause for concern?Research shows once more that vaccination protects against long COVID, but the timing of the jab may be important. Generations of teenagers have found a way to smoke weed — legal or not. So what do we know about the effects on the brain?And the Declaration of Helsinki has turned 60 years old. Are these ethical principles that guide clinical research up to scratch?