A review of 22 studies found that drinking juice made from fresh fruits and vegetables or blended powder concentrate improved folate and antioxidant levels, including beta-carotene, vitamin C and vitamin E ().

Bottom Line: If you struggle to eat enough fruits and vegetables each day, juicing is a convenient way to get a wide range of important nutrients.

There's plenty of evidence linking whole fruits and vegetables to reduced risk of disease, but studies for fruit and vegetable juices are harder to find.

One review reported that the health benefits of fruits and vegetables may be due to antioxidants, rather than fiber. If this is true, then juice may provide comparable health benefits to whole produce ().

However, there is only weak evidence that pure fruit and vegetable juices can help fight cancer. There is a lack of human data and other findings are inconsistent ().

Nonetheless, other areas of health show more promise. For example, juices may reduce the risk of heart disease. Apple and pomegranate juices have been linked to reduced blood pressure and cholesterol levels (, , ).

Additionally, consuming fruit and vegetable juices in liquid form or blended concentrations may reduce homocysteine levels and markers of oxidative stress, both of which are linked to improved heart health ().

One large study found that the risk for Alzheimer's disease was reduced among those who drank fruit and vegetable juices three or more times per week, compared with those who drank juices less than once per week ().

The reduction in Alzheimer's risk may be due to the high levels of polyphenols in the juices. These are antioxidants found in plant foods, believed to protect brain cells.

Despite these results, more studies are needed to better understand the health effects of fruit and vegetable juices ().

Bottom Line: Limited evidence is available to link fruit and vegetable juice to a reduced risk of diseases like cancer, Alzheimer's and heart disease.

Juicing advocates often claim that drinking juice is better than eating whole fruits and vegetables.

They justify this by saying that removing the fiber makes nutrients easier to absorb.

However, there isn't any scientific research to support this.

You may actually need the fiber content of the fruit or vegetable to experience the plant's full health benefits ().

For example, important antioxidants that are naturally bound to plant fibers are lost in the juicing process. These may play an important role in the health benefits of whole fruits and vegetables (13, , ).

In fact, up to 90% of fiber is removed during the juicing process, depending on the juicer. Some soluble fiber will remain, but the majority of insoluble fiber is removed.

One study compared whole apples to apple juice. It found that drinking clear apple juice increased LDL cholesterol levels by 6.9%, compared to whole apples. This effect is thought to be due to the fiber content of whole apples ().

An observational study showed an increased risk of type 2 diabetes in people who consumed fruit juices, whereas whole fruits were linked to a reduced risk ().

People also tend to feel more full when they eat whole fruits, compared to when they drink the juice equivalent (, , ).

One study compared the effects of blending and juicing on the nutrient content of grapefruits. Results showed that blending, which retains more fiber, is a better technique for obtaining higher levels of beneficial plant compounds ().

Should You Add Fiber to Your Juices?

The level of fiber in your juices will depend on what type of juicer you use, but some sources suggest adding leftover pulp to other foods or drinks to increase fiber intake.

Although this is better than throwing the fiber away, evidence suggests that re-adding fiber to juice doesn't give you the same health benefits as simply eating whole fruits and vegetables ().

Additionally, a study found that adding naturally occurring levels of fiber to juice did not enhance feelings of fullness ().

Bottom Line: Eating whole fruit and vegetables is better for your health. Juicing makes you miss out on beneficial fiber and antioxidants.