Is your favorite treat changing your brain? Why do so many snacks melt in your mouth? And why can’t Stephen replicate his favorite salad dressing? Take the Seven Deadly Sins survey: <a href="http://freakonomics.com/nsq-sins/">freakonomics.com/nsq-sins/</a>

138. Why is Everyone Having Less Sex?

Research psychologist Angela Duckworth (author of "Grit") and tech and sports executive Mike Maughan really like to ask people questions, and they believe there’s no such thing as a stupid one. So they have a podcast where they can ask each other as many “stupid questions” as they want. New episodes each week. "No Stupid Questions" is a production of the Freakonomics Radio Network.

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