WINTER PARK, Fla. -

Do you juice?  The food trend is a multi-billion-dollar industry and still growing.

With juice bars popping up all over the country, many people are beginning to think they can sip their way to a skinnier, healthier body. But is it safe?

Those who juice swear by it, saying it reduces your risk of cancer, boosts your immune system, helps digestion, and just plain makes you feel better.

But should it become your main source of nutrition

Joy Finnegan believes in a healthy balance between diet and exercise.

"I definitely work out and I try to do cardio as well," says Finnegan. "Whenever I don't have the time, I do weights and I keep a healthy diet always."

She started juicing two years ago for the supposed health benefits.

"One of my friend's fathers was sick, so they started juicing to clean out his body," says Finnegan. "So I picked up on it after I realized it helped him quite a bit."

Buy Joy quickly discovered that busy women can't live on fruit juice alone.

"I just have a large appetite and I'm very active, so I've never gone on an 'only juice diet' for an extended period of time. Not more than two days at least," says Finnegan.

After two days of juicing, she was starving.

"I needed food immediately on that third day," says Finnegan.

Imagine if Joy would have juiced for seven days straight. Sounds nearly impossible, but a growing number of women are giving up food for a bottle of greens, carrots, or blueberries, in order to lose weight.

"People may feel great because they lost 10 pounds in one week," says Dr. Yana Finkelshteyn. "Are they going to gain it back as soon as they start eating real food? Absolutely."

Finkelshteyn says juicing does have its benefits and is OK as a supplement or a single meal replacement.

But the doctor warns that women should be leery of juicing to cleanse or detox.

"There's nothing about fruit or vegetable juice that's going to detox your body," says Dr. Finkelshteyn. "We have organs for that. Your liver and kidneys do that and there's nothing about consuming juice that's going to speed up that process."

The popular organic restaurant Cafe 118 in Winter Park offers a number of all-natural juice blends.

"We have beet and apple, we have pineapple, celery and mint, we have orange," says Joe Diaz, owner of Cafe 118. "Then we have the green glow, and we have plenty of smoothies as well."

Diaz encourages customers to use the juices as a daily supplement.

"It should be a staple of your diet, the same way that you eat meat or chicken or fish, and you think you need that much chicken, fish, or meat for protein, you need this much for minerals," says Diaz.

If you do try juicing at home, make only as much juice as you can drink at one time, because fresh-squeezed juice can quickly develop harmful bacteria.