2. Growth and Impact

Steph McGovern turns her attention to the role of salt in our diet.

In the conclusion of her two-part investigation, she begins in Anglesey at the Halen Mon sea salt company, learning how they produce their salt from the waters of the Menai Straits. Then Steph moves on to learn more about the wide variety of artisan salts that have become so popular in recent years - from French Fleur du Sel to the beautiful pink Himalayan Rock Salt.

Steph goes on to address the issue of salt and health, hearing from a campaign group promoting the lowering of salt consumption down to 6 grams a day through schemes such as reducing the number of holes in chip shop salt shakers.

Finally Steph heads down the salt mine at Winsford in Cheshire, with 160 miles of tunnels and an off-shoot storage facility that capitalises on the ideal humidity by storing everything from grand pianos and barrel organs to unwanted waxworks.

Producer: Geoff Bird

First broadcast on BBC Radio 4 in February 2015.