Cold brew is made using a different process than hot coffee or iced coffee. Cold brew is less acidic, but hot coffee has more antioxidants.

Yahoo: What's the Difference Between Cold Brew and Iced Coffee? Experts Spill the Beans

What's the Difference Between Cold Brew and Iced Coffee? Experts Spill the Beans

Cold brew and iced coffee may look similar, but they’re worlds apart in how they’re made, how they taste, and how they hit your system. Cold brew steeps coffee grounds in cool water for hours, ...

New York Post: This Starbucks iced coffee offering has the most caffeine — here’s what to order to get more bang for your buck

This Starbucks iced coffee offering has the most caffeine — here’s what to order to get more bang for your buck

NBC News: Iced coffee drinkers can get a cheaper caffeine fix at home this summer

Iced coffee drinkers can get a cheaper caffeine fix at home this summer

The most common sources of caffeine for human consumption are the tea leaves of the Camellia sinensis plant and the coffee bean, the seed of the Coffea plant. Some people drink beverages containing caffeine to relieve or prevent drowsiness and to improve cognitive performance.

Up to 400 milligrams (mg) of caffeine a day seems safe for most adults. That's about the amount of caffeine in four cups of brewed coffee, 10 cans of cola or two "energy shot" drinks. Keep in mind that the caffeine content in drinks varies widely.