Research going back decades shows adding more fruits, vegetables, and non-animal sources of protein helps us live longer, healthier lives.  A study featured in the Netflix docuseries You Are What You Eat: A Twin Study took that to the next level.  Stanford researchers asked 22 sets of identical twins to go 8 weeks eating a healthy, varied diet and regularly exercising. One twin ate an omnivore diet, the other vegan. On this week’s episode of Well, Now we talk to the lead researcher of the “twin study” Christopher Gardner on his findings and whether we really all need to go vegan to stay healthy. If you liked this episode, check out: How Your Food Can Fight Climate Change Podcast production by Vic Whitley-Berry with editorial oversight by Alicia Montgomery. Send your comments and recommendations on what to cover to [email protected]. Want to listen to Well, Now uninterrupted? Subscribe to Slate Plus to immediately unlock ad-free listening to Well, Now and all your other favorite Slate podcasts.  Subscribe now on Apple Podcasts by clicking “Try Free” at the top of our show page. Or, visit slate.com/wellplus to get access wherever you listen. Learn more about your ad choices. Visit megaphone.fm/adchoices