Author: BBC World Service

Smartwatches are increasingly popular and many of us use these wearable devices to monitor our performance and improve our fitness. But how reliable is the data they collect, and can they actually make us healthier?

CrowdScience listener Caitlin from Malawi is a big fan of her smartwatch. Her husband Fayaz, however, is much more sceptical of its accuracy, and has asked us to investigate. We meet up with them both at the gym, where Caitlin and presenter Caroline Steel put their fitness trackers – and themselves – to the test.

We visit public health researchers Dr Cailbhe Doherty and Rory Lambe, who investigate the accuracy of wearable consumer devices, at University College Dublin. Caroline again pushes herself to the limit to see how her smartwatch results measure up to those from gold standard laboratory equipment.

But is it crucial for smartwatches to be accurate? If they get us off the couch, is that what makes the difference to our health? Health behaviour expert Dr Ty Ferguson from the University of South Australia has studied this very question. And finally, how does quantifying our every move affect the way we think about ourselves and how we live? Professor Deborah Lupton from UNSW Sydney, shares some insights.

Presenter: Caroline Steel Producers: Jo Glanville and Sophie Ormiston Editor: Cathy Edwards Technical producer: Sarah Hockley Production co-ordinator: Ishmael Soriano

Celebrations for the Lunar New Year kicked off on 29th January, and this year is the Year of the Snake.

We start things off by discussing the purpose of some mysterious serpent markings on the banks of the Orinoco River.

Next, we find out about the origins of snake oil, before digging into the psychology of why we trust snake-like people.

Plus, herpetologist Dr Mark O’Shea tells us all about his work identifying snakes, and what happened when he got bitten.

That, plus many more Unexpected Elements.

Presenters: Marnie Chesterton, with Chhavi Sachdev and Christine Yohannes. Producers: Dan Welsh, with Alice Lipscombe-Southwell, William Hornbrook and Imaan Moin.

Nasa's OSIRIS-REx mission to collect a sample from an asteroid has been a great success. Asteroid Bennu's sample yields a watery pool of history, thanks to an international team of scientists including the London Natural History Museum's Sarah Russell.

Also, in a week of tumultuous changes to federal funding and programmes, we hear from some US scientists affected and concerned by Executive Orders from the White House. Betsy Southwood, formerly of the Environmental Protection Agency, is worried not just about the government employees’ careers, but the environment itself and the whole of environmental science in the US and the world. Chrystal Starbird runs a lab at the University of North Carolina and is worried about the fate of grants aimed at diversifying scientific expertise, but also that some grant schemes are getting erroneously included in the anti-DEI clampdown. And Lawrence Gostin is an eminent health lawyer, proud of the NIH and all it has achieved.

Presenter: Roland Pease Producer: Alex Mansfield Production co-ordinator: Jana Bennett-Holesworth

(Photo: OSIRIS-REx Sample Return. Credit: Nasa/Getty Images)