Why does sex make you sleepy?

Is the flipping of Earth's magnetic field a concern? Why might half-filled ice cube trays freeze faster? Why does sex make you sleepy? Why might you get an 'electric shock' from moving your head? Is nicotine addictive? Why does scratching an itch feel so good? Why do we have different blood groups? What are statins? Could we ever see the dark side of the moon? Dr Chris Smith and Clarence Ford have all the answers... Like this podcast? Please help us by supporting the Naked Scientists

Dr Chris answers listener questions including: do men and women have an equal chance of getting sports injuries? What health benefits can a sugar free diet bring? Why does my sock shift around my foot at night? How should we navigate testosterone levels in women's sport? How can we treat hypertrophic cardiomyopathy? Is 'biowater' a marketing gimmick? Like this podcast? Please help us by supporting the Naked Scientists

Dr Chris is back to answer listener questions. Why do cat's eyes reflect bright colours? What are the short, high pitched ringing noises that can sometimes be heard? What causes Bell's palsy? Will botox help keep my eyelid up? Like this podcast? Please help us by supporting the Naked Scientists

Do animals feel fear the same way that we do? Do diet supplements boost your immune systems? Can using phones and headphones change the shape of your body? Why don't birds get electrocuted on pylons? Is the northern hemisphere more 'innovative' than the south? Dr Chris Smith and Relebogile Mabotja have all the answers... Like this podcast? Please help us by supporting the Naked Scientists

Dr Chris takes on more listener questions. Including: is Chinese medicine separate from Western medicine? Why do we sometimes cry in response to feelings of sadness and joy? Why do I have a blotch in my vision after looking directly at a light source? Why do kids cry when they get injured, but adults less so? What happens if I scratch a mosquito bite? What is the relationship between science and religion. Like this podcast? Please help us by supporting the Naked Scientists

The questions keep coming for Dr Chris. This week they include: have scientists got their hands on the oldest ice ever studied? Does putting the air conditioning on too high or low make you ill? What factors contribute to chronic mental illness? How do you reduce puffiness under the eyes? Can cold weather make healed operation sites sore again? Like this podcast? Please help us by supporting the Naked Scientists

Why does cold water take your breath away? And why is it cold when you leave the cold water? What smells does an ant produce? Is there a psychological aspect to cramp? Are there any new asthma treatments in the pipeline? Are people getting vaccinated against cancer? Dr Chris Smith and Clarence Ford have all the answers... Like this podcast? Please help us by supporting the Naked Scientists

Dr Chris answers listener questions including: what is the Higgs boson? How should I change my lifestyle to prevent diabetes? Why can you pass on yawns? Why does nerve pain/sciatica get worse when we're tired? Like this podcast? Please help us by supporting the Naked Scientists

Dr Chris with more answers to listener science questions: why was the discovery of the Higgs boson worthy of a Nobel Prize? Are birth rates falling around the world? How do we prevent HPV? Like this podcast? Please help us by supporting the Naked Scientists

Can a mobile phone between the legs affect fertility? Why does wet cornflour stiffen when squeezed? Does light at night affect reproductive success of local animals? Can animals smell fear? And what actually is IQ? Plus, Dr Chris explores how animals are evolving in response to the influence of humans... Like this podcast? Please help us by supporting the Naked Scientists