New Yorker staff writer Maria Konnikova returns to play "Is That Bullshit?" This week, the persistent nutritional myth about vitamin C. The actual vitamin, not the singer. Maria's most recent book is The Confidence Game. Plus, one of Barack Obama's dreams has finally been realized: a plain white t-shirt store is open in Hawaii.

Sponsors:

ZipRecruiter. Post your job listing to all the top job sites with a single click. Try it for free by going to ZipRecruiter.com/gist.

And Blue Apron. Blue Apron's meal kits are delivered right to your door and make cooking at home easy. Get your first three meals free by going to BlueApron.com/gist.

Join Slate Plus! Members get bonus segments, exclusive member-only podcasts, and more. Sign up for a free trial today at Slate.com/gistplus.

Learn more about your ad choices. Visit podcastchoices.com/adchoices

Hosted by Simplecast, an AdsWizz company. See pcm.adswizz.com for information about our collection and use of personal data for advertising.