Author: BBC World Service

In the past stout beer has been touted for its supposed health benefits. Is there any truth to those claims - and what happens if you take the alcohol out?

CrowdScience listener Aengus pondered these questions down at the pub, after noticing most of his friends were drinking non-alcoholic beers. He wondered how the non-alcoholic stuff is made – what’s taken out and what’s added in – and whether the final product is better for you than the alcoholic version.

It’s a question that takes us to Belgium, home to the experimental brewery of a global drinks company which takes the growing market for alcohol-free beer very seriously. David De Schutter, head of research and development, shows host Marnie Chesterton how to take alcohol out of beer without spoiling the flavour.

We also find our way to a yeast lab in Leuven, Belgium where Kevin Verstrepen and his team have found another way to make alcohol-free beer with the help of industrious microbes: yeast varieties that brew beer without producing any alcohol in the first place. And how do they compare to the alcoholic versions? We discuss the importance of aromas in our perception of beer’s taste.

So should listener Aengus stick to non-alcoholic stout? We speak to scientist Tim Stockwell about the health drawbacks of alcohol, even in moderation. And gut microbiome researcher Cláudia Marques fills us in on her delicious pilot study, which looked at the effects of both non-alcoholic and alcoholic beers on our digestive tract.

Along the way, Marnie taste-tests what's on the market, and asks the experts why this particular grocery shelf has become so much bigger and more flavourful in recent years.

Presenter: Marnie Chesterton Producer: Sam Baker Editor: Cathy Edwards Production co-ordinator: Ishmael Soriano Technical producers: Giles Aspen, Andrew Garratt and Donald MacDonald

(Image: Close-up of waitress holding craft beer at bar, Brazil Credit: FG Trade via Getty Images)

Team Unexpected have been digging into their mind palaces to pull on the scientific research that has stuck with them most over the past year. We hear from Professor John Parnell, geologist at the University of Aberdeen, about the role of plankton in forming ancient mountains. How ocean bubbles play a role in climate regulation with bubble physicist Dr Helen Czerski from University College London. Would you know how to measure the size of a bubble? We also participate in some memory sports with Jonas von Essen who is a two-time world memory champion. He helps us construct a mind palace in order to memorise really long strings of digits. Plus we look into the backstory of the human buttocks with science journalist and reporter Heather Radke. She answers the question ‘why do we humans have such large behinds?’ And we hear from Professor Andre Isaacs at the College of the Holy Cross who has filled his chemistry lab with music and dance in order to change perceptions about who can be a scientist. That, plus many more Unexpected Elements.  Presenter: Marnie Chesterton Producer: Jonathan Blackwell and Harrison Lewis with Imaan Moin and Alice Lipscombe-Southwell

H5N1 bird flu is still spreading across farms in the USA and this week claimed its first human life in North America - an elderly patient in Louisiana infected by backyard poultry. But last week, Sonja Olsen, Associate Director for Preparedness and Response in the CDC’s flu division, and her colleague Shikha Garg, published new analysis in the New England Journal of Medicine summarizing the human cases and epidemiology so far.

A lab study underscoring a suspected link between the virus responsible for cold sores, and Alzheimers, the most common form of dementia, has been published in Science Signalling this week. The study, by Dana Cairns of Tufts University, looks at whether repetitive brain trauma – another risk factor - adds to the evidence that latent herpes simplex can be involved.

Song Lin, a chemist at Cornell University who has won prizes for pioneering the use of electrical currents to drive chemical reactions rather than heat, has teamed up with Cornell micro engineer Paul McEuen to power up a new kind of chemistry and invent another kind of SPECS – an acronym for Small Photoelectronics for Electrochemical Synthesis. They outlined their first generation device and the promises it brings in Nature this week.

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

(Photo: Chickens eating feed. Credit: San Francisco Chronicle/Getty Images)

When listener Diana fell on a run on her birthday, her first instinct was not to check her bruised hand, but instead to get up as quickly as possible and act as if nothing had happened. She felt embarrassed. Meanwhile, her son Marley loves to watch fail videos that, mostly, show people falling over. So why does falling – something that can cause serious injury – elicit both embarrassment and laughter?

In the name of CrowdScience, presenter Caroline Steel trips, stumbles and falls. She spends a morning with clown Sean Kempton who teaches her slapstick skills, including how to do it safely.

Psychologist Rowland Miller explains why falling can be embarrassing and shares his theory of why humans have developed this emotion in the first place. Then it’s time for Caroline to try out Diana’s predicament herself. If a BBC presenter falls in a park, will she feel embarrassed? From embarrassment to laughter, psychologist Janet Gibson lists the ingredients of a funny fall, and humour expert Caleb Warren explains how they can get funnier with distance. Then Caroline tries, semi-successfully, to make members of the public laugh. Will clown Sean do a better job?

Presenter: Caroline Steel Producer: Florian Bohr Editor: Cathy Edwards Production coordinators: Ishmael Soriano Sound engineers: Bob Nettles, Tim Heffer and Giles Aspen