Can raw potato juice really induce weight loss?if so how?what about mangoes & almonds?

Weight loss: I wouldn't doubt that anything can induce weight loss, but there is no sufficient proof that anything besides a healthy diet, low in calories, starch & sugar, with vitamin support and reasonable daily exercise, is reliable. Some form of protein and vegetables throughout the day will get you there.

No: Weight is a matter of calories in vs. Calories out. Many factors influence how quickly your individual body burns calories, such as exercise level, time of day, hormones, source of calories etc.; but the bottom line is still calories in vs. Calories out. There is no magic medicine, herb, or supplement, although some of these help a little.