There are two kinds of juice I’d like to evaluate here: Fruit juice and Vegetable Juice…Let’s take a look at fruit juice first:
Fruit Juice 
If you have a choice between drinking a glass of orange juice or eating the fruit – eat the fruit. Here’s why:
Fruit juice normally lacks the fiber (in the skin) from the original fruit, along with vital nutrients from the fruit’s pulp, that help the body digest the fruit and provide those nutrients to the body. The sugar in juice becomes highly concentrated causing the blood sugar to rise more quickly. Also, the level of sugar can be higher.
For example, 120 calories of a whole apple contains 24g of sugar while a glass of apple juice can have 30g.
Additionally, many commercial juices have added sweeteners like sucrose or high fructose corn syrup which pose their own unique dangers to our health (more about high fructose corn syrup in a separate article).
Bottom Line: Here’s the order of choice:
#1 Eat the whole fruit.
#2 Drink 100% natural fruit juice (no added sugar)
#3 Drink the sweetened juice (if you’re dying of thirst and it’s the only game in town)
An occasional juice can be refreshing and hydrating…just be aware of your hydration needs for that day and adjust accordingly.
Personal Note: About orange juice…I read years ago that because the acid in this juice bypasses the digestive tract it can have a drying effect on the skin. So, if you are having skin problems and you drink lots of orange juice, there might be a connection.
Vegetable Juice 
The “sugar” effect is present here as well except that the level of sugar is lower. An occasional veggie juice when the mood strikes and you’re thirsty is ok, but not on a regular basis…no fiber.
Contrary to popular belief juicing is not healthier than whole veggies…quite the opposite…much of the vegetable is left behind – pulp and the fiber which contain vital nutrients. and it’s very expensive because a high quantity of vegetables are needed to make a small amount of juice.
Personal Note: I tried juicing once with a well known brand of juicer and was disappointed in the results. 
So much pulp was stuck inside and so little juice came out. It was a mess. I have a blender which some experts recommend as a better choice, but I wouldn’t try to blend carrots in it. I’m liable to have it explode in my face or burn out the motor. 
Bottom Line: Juice is a good occasional drink for hydration, especially if it’s a choice between juice and soda when you’re out and about. Just remember that you might be missing the important parts so adding some whole fruit and vegetables on those days would be wise.
If you can afford a juicer or blender that keeps the veggies intact so you get the entire vegetable, pulp, and fiber into your juicer at home…go for it. I can imagine a blend of carrots, celery, kiwi and watermelon might taste great. If anyone has a juicer that does this I’d like to know about it…I’d like to make a juice of carrots with celery and some seedless watermelon!
Food for Thought!
http://www.whfoods.com/genpage.php?tname=george&dbid=24
https://medlicker.com/892-orange-juice-bad-for-you
