Juice Plus® is a dietary supplement made of 17 fruits, vegetables, and grains. It was created to reinforce fruit and vegetable consumption, which often falls short of the recommended daily intake; it is not meant to take the place of eating fruits and vegetables, however. Juice Plus® claims to improve overall health and cites several self-funded studies to support this. Not everyone in the medical field accepts these claims. Juice Plus® usually has no side effects, but they do occur for some people.

This concentrated juice powder is derived from apples, beets, berries, black and red currents, broccoli, cabbage, carrots, and acerola cherry. It also contains Concord grape, cranberry, kale, oranges, peaches, papayas, parsley, pineapple, spinach, and tomato. B vitamins, and carotene and vitamin E, are added to this blend. The company is quite clear that this product is not meant to be a substitute for eating fruits and vegetables, but is to be used only as an addition to an already healthy diet.

The manufacturers claim that the level of antioxidants and folate increases after drinking the juice. They also claim that the juice decreases the markers of inflammation, works to support the immune system, and protects the structural integrity of DNA. Cardiovascular health may also be improved by lowering homocysteine levels and maintaining the flexibility of the arteries.

The main criticism of Juice Plus® comes from a major cancer clinic in New York. The clinic suggests that the amount of fruit and vegetable powder is too small to make any real difference in a person's health. It is also critical of the impartiality of prior studies because nine of the studies were funded by the manufacturer or main distributor. Only one study was completely independent.

Side effects are generally rare for those who use Juice Plus®, but some study participants did develop hives. About a third of people using the product for seven days developed respiratory tract, urinary, and/or musculoskeletal complaints. Other participants withdrew from studies because of gastrointestinal side effects. Perhaps the most serious side effect was liver toxicity, which developed in a middle-aged patient with endometrial cancer; this reversed after the juice was stopped.

According to the Memorial Sloan-Kettering Cancer Clinic, Juice Plus® should not be taken by anyone undergoing chemotherapy without first consulting a healthcare provider. The antioxidants in the juice could interfere with some medications. The clinic recommends that cancer patients use Juice Plus® very cautiously.