Sumner joins as publishing manager and takes up his new post immediately. He replaces Richard Johnstone, who was last month promoted to the position of publishing director of Wallpaper*.
As well as his responsibilities on Slimming and Here's Health, Sumner launched women's health title Celebrity Bodies for Emap last year.
Sumner spent most of the formative years of his career in magazine production and working as a freelance journalist for titles including, among others, IPC Ignite's Uncut.
Eric Fuller, publishing director of Loaded, said: "I'm delighted that Andrew has chosen to join us at Loaded. He is an experienced, hands-on publisher with a real understanding of how magazines work and a great feel for the men's market. He will play a major role in keeping Loaded at the top of its game."
Last week, a new entrant Jack was launched into the men's magazine market by Loaded founder James Brown, now CEO of publisher I Feel Good.
Brown was seen to have revolutionised the men's publishing sector with Loaded, and UK publishers are watching with interest to see how successful Jack will be.
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