Commuters rushing through Back Bay Station have a healthier alternative to coffee and doughnuts, thanks to Juice, a tiny sliver of a shop right by the station’s Dartmouth Street doors. Juice is what Juice does, in both bottled form and made-to-order (starting at $5.95 for 12 ounces). The store also offers acai bowls, smoothies, and “boosts” such as spirulina and bee pollen to add to your drink. Co-owner Ron Marcos says the Number 6 — spinach, kale, apple, celery, lemon, ginger — is a popular choice; sounding a bit like an oenophile, he calls it a “nice medium-bodied juice with a sweet finish.” Be prepared to wait if you come during the lunch rush. On the plus side, you can watch as your fruits and veggies are transformed from solid to liquid. Marcos says produce is delivered at least once a day, sometimes more. “We don’t have space to store it, so everything is made fresh.” Juice, 145 Dartmouth St., Boston, 617-418-9879, www.juicebarboston.com. JANE DORNBUSCH