Is it brussel sprouts or brussels sprouts? How do you spell it? Based on Google search trends in 2016, the ratio of people looking for brussel - without the "s" - is nearly 600% higher than the spelling of it with the "s" on the end. But just because everyone is doing it, that doesn't necessarily mean it's the correct right way!
Named after the region of Belgium where it has been a historically popular vegetable, the correct spelling is actually Brussels sprouts. Despite being more popular, the other is a misspelling. If you want to get real technical, the "B" should also be capitalized in the name since it's an ode to a proper name of a city/region. Though admittedly, we hate capitalizing it too even though you're supposed to.
In the same family as broccoli, cauliflower, and kale, this cruciferous vegetable is a good source of antioxidants. This ORAC test looked at the phenolic activity of a random sample which was bought at a grocery store, restaurant, cafe, or marketplace in Norway. Even though cooking will reduce how much active antioxidants there are, the amount remaining should still be high based on patterns seen in related vegetables like broccoli before and after preparation.
Research Support, Non-U.S. Gov't: Carlsen MH, Halvorsen BL, Holte K, et al. Nutrition Journal NIH Jan 2010