© Denzil Green
There isn't really any such as thing as Baby Carrots as sold in stores.
There are "regular" carrot cultivars that can be harvested young. They will still be long, but they will be thinner than ones allowed to fully mature. You could say they were harvested as "babies", but they're more like teenagers. You wouldn't want actual baby sizes of these carrots: you would get something the size of a toothpick.
And there are carrot cultivars that mature at much smaller sizes than other Carrots. Examples include some types of Nantes Carrots, or Planet Carrots. These types of carrots evolved (or were developed) to be much shorter than other carrots, so that they wouldn't need to struggle growing down into soils that were dense (longer carrots prefer fluffy, loose soil.) There is for instance one variety of Nantes carrots which grows to be only up to 4 inches (10 cm) long, which is sometimes sold as a "Baby Carrot."
That being said, however, what you buy in small plastic bags in grocery stores may not even be any of the above. They are often just small, baby-carrot looking pieces carved out of large, fully-matured Carrots. The real name for these is actually "Baby Cut" Carrots, but marketers will often use the abbreviated term. Generally, processors get about three "Baby Carrots" out of one large carrot.
Look closely at the stem end of your Baby Carrot: if it doesn't look real, it may well just be green food dye to make the top of the piece look as though a stem had been there. Owing to the work involved and the demand for Baby Carrots, they are able to sell these faux-babies for twice the price of what the full-size Carrots would have commanded. Unless you see the stems attached, assume that the Baby Carrots you are buying are just pieces of full-sized Carrots.
If you want to pay the extra for the shape, or for the convenience of having the pieces already peeled and washed for you as a quick, healthy snack food, do so, but don't do so thinking you're getting superior taste: true small carrots, such as those of the Nantes or Planet types, will be milder and sweeter.
Good source of vitamin A. Also contains some protein, carbohydrate, folacin and fibre.
Per 1 pound (450g) bag of baby carrots: 242mg sodium