Fruit juices may be considered an "orange light food" in Whole Food Plant-Based circles:

Dr Esselstyn asks us to cut out fruit juices completely! See Esselstyn FAQ:

Dr McDougall has several dressing recipes with OJ: here, here and here, for example.

Dr Greger has a bunch of videos on fruit juices — several fruit juices have been shown to improve our health. But at the end of this video: The Healthiest Fruit Juices (5 mins, 2023), he concludes:

• Those who follow Dr Esselstyn may diligently avoid fruit juices.
• Others may choose to use small quantities of fruit juice for making dressings (like Dr McDougall's recipes).
• Or we may choose to eat whole fruits instead of fruit juices, as Dr Greger recommends.

How is it made? Fruit juice concentrate is made from fruit juice through evaporation, filtration, or membrane processes, resulting in a thick, syrupy liquid.

High calorie density: The calorie density of concentrated fruit juice is much higher than fruit juice. In Whole Food Plant-Based guidelines, we strive to consume lower calorie density foods like vegetables, fruits, beans and whole grains: see Calorie Density; consuming higher calorie density foods promotes weight gain.

Added Sugars: Concentrated Fruit Juice gets classified as Added Sugar by organizations like CDC and AHA (American Heart Association).

American Heart Association dietary guidelines from 2021 classify Concentrated Fruit Juices as Added Sugars:

Source: 2021 Dietary Guidance to Improve Cardiovascular Health: A Scientific Statement From the American Heart Association, Circulation, Volume 144, Number 23.

Source: Get the Facts: Added Sugars at CDC website.

Ornish Lifestyle Medicine classifies Concentrated Fruit Juices as Added Sugars:

Source: Understanding Sugar: Added vs.Natural at Ornish Lifestyle Medicine.

Fruit juice may be considered health promoting (as compared to Standard American Diet), as Dr Greger explains in his videos at NutritionFacts. Still, Dr Greger recommends consuming whole fruits instead of fruit juices because whole fruits have more nutrition.

Dr Esselstyn strictly forbids fruit juice for optimum heart health.

If we transform fruit juice into concentrated fruit juice, the resulting product gets classified as Added Sugar, something we should strive to minimize.