On this episode of Slate Money, Felix Salmon of Fusion, Cathy O'Neil of mathbabe.org, and Slate's Moneybox columnist Jordan Weissmann are joined by special guest Elly Trickett, editor-in-chief of IBM.com and former director of content for Weight Watchers. They discuss:

• How weight loss programs make money

• The enduring trend of wearable fitness tech

• The economics of gym memberships and yoga studios

Felix’s number: How Americans got so fat.

Under Armour's new UA Record fitness app.

Check out other Panoply podcasts at itunes.com/panoply.

Email: [email protected]

Twitter: @Felix salmon, @mathbabedotorg, @JHWeissmann

Podcast production by Zachary Dinerstein

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