Modern life is not good for us. Most of us know we are fatter, less fit and more stressed than ever before. And all of us want to be healthier, but with temptation everywhere, it's incredibly hard. Hugh Fearnley-Whittingstall and Steph McGovern are determined to help us all fight back, revealing the easy fixes to dramatically improve our diet, fitness and mental wellbeing.

This week Hugh and Steph challenge one community to test out easy solutions for their compulsive snacking. The doctors and nurses at Llandaff Surgery in Cardiff work such long hours that they live off an endless supply of cakes and biscuits to get through the day. Hugh and Steph want to trial two contrasting solutions, adding a bit of competition to spice things up. Hugh wants to test the latest science around the surprising power of peppermint, while Steph wants to test out a study that showed how putting a 25-second time delay on the snack cupboard could curb our cravings.

But if they’re cajoling others to live well, then Hugh and Steph feel it’s only fair that they walk the walk themselves. Like 40% of us, Steph suffers from a dodgy stomach but doesn’t know why. And Hugh wants to tackle what’s been called the health epidemic of the 21st century – stress.

Helping them sift through the maze of scientific research is Dr Zoe Williams, who will be helping them find smart and surprising ways of tackling their health concerns. For Hugh she suggests trying cold water therapy – essentially immersing yourself in freezing temperatures for three minutes at a time. And after a rather intimate test of Steph’s bowels, she embarks on a new regime to look after her gut health.

Steph also meets one young family struggling with screen time addiction, suggesting simple ideas to make it easier for the whole family to spend time together. Meanwhile, Hugh investigates the multi-million pound industry of electric muscle toners, who effectively sell a six-pack in a box. The question is, do they actually work? Show less