Unmarried parents spend, on average, several hundred dollars less on each child annually. fizkes/Shutterstock.com

A quarter of US parents are unmarried – and that changes how much they invest in their kids

Orestes 'Pat' Hastings, Colorado State University; Daniel Schneider, University of California, Berkeley

Single parents and unmarried parents who live together spend less on their children than married parents.

Some people believe that putting collagen in your coffee will bring good health, but collagen in coffee does nothing good for you. Imagepocket/Shutterstock.com

Collagen in your coffee? A scientist says forget it

Brooke Russell, Texas A&M University

A protein called collagen keeps us connected by keeping our tissues together. In recent years, it's gained popularity for restoring aging skin, with some people even saying you should drink it.

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