Robert Downey Jr. Reveals His 5 Favorite Instagram Accounts -- Including 'Science Bro' Mark Ruffalo!

Happy Birthday, Instagram!
To celebrate the fact that the social media platform is officially five-years-old, some of the biggest insta-celebs are naming their favorite accounts to follow.
ETonline is exclusively revealing the five top Instagram accounts that Marvel mega-actor, Robert Downey Jr., loves to double tap the most.
1. Beth Stern (@Bethostern)
RDJ's Reasoning: "Sterns and cats."

2. Bow & Arrow (@BowandArrow78)
RDJ's Reasoning: "I’m a sucker for Bruce Lee merch."
3. Banksy (@BanksyNY)
RDJ's Reasoning: "Iconoclast."
4. Mark Ruffalo (@markruffalo)
RDJ's Reasoning: "#ScienceBros."
5. Robert Downey, Jr.(@robertdowneyjr)
RDJ's Reasoning: "Gotta love yourself."

What are your favorite accounts to follow on Instagram? Share your thoughts with @ETnow on Twitter!
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