Bruno Mars puts margarine in his hair.
The 26-year-old singer - who is renowned for his impressive quiffed hair - uses a number of unusual natural ingredients to keep it as big as possible, including the butter substitute and berries.
He said: ''I call my hairstyle the Wamp and Stomp. I can't give you exact measures but it's a lot of margarine, natural fruit juices and berries and, surprisingly, barbecue potato Popchips.
''It stays in place for a while after that.''
Using the unusual combination of products on his hair might not be a problem for Bruno, but should fellow star Amanda Seyfried - who has previously dated Dominic Cooper and Ryan Phillippe - use the same goods she may illicit some unusual looks, as she has previously revealed she rarely washes her locks.
Asked for her hair care advice, 'Red Riding Hood' star Amanda said: ''Don't wash it! I wash my hair every three days which is something I would've never imagined years ago, but I also use dry shampoo and my hair is even healthier.''