Noni juice (Morinda citrifolia) is a globally popular health drink originating in the tropics. A review of published human clinical trials reveals that noni juice may provide protection against tobacco smoke-induced DNA damage, elevated blood lipids and homocysteine, and systemic inflammation. Human intervention studies also suggest that noni juice may improve joint health, increase physical endurance, boost immune activity, inhibit protein glycation, aid in weight management, help maintain bone health in women, help maintain normal blood pressure and blood sugar levels, and improve gum health. Furthermore, these studies show that noni juice possesses remarkable antioxidant activity, more so than the other fruit juices that were used as placebos. It is this antioxidant effect, and its interaction with the immune system and inflammatory pathways, that could explain many of the observed health benefits of noni juice. Recent research has shown that antioxidant benefits can occur within an hour of ingestion. Furthermore, the main commercial source of noni juice, Tahitian Noni Juice, has been shown to be safe for daily human consumption.