Green coffee bean extract is it safe?

Green coffee bean extract is it safe? My sister asked ... I never watched the show dr. oz on tv about the benefits and side effects of green coffee. He explained that; This supplement is able to lose weight quickly without any side effects, if served according to the rules. this extract, can reduce a person's appetite, so it can indirectly help the diet.

(http://en.wikipedia.org/wiki/Coffee_bean)

Green coffee bean content:
The term “green coffee bean” refers to unroasted mature or immature coffee beans. These are processed by wet or dry ways for removing the outer pulp and mucilage, associated have an intact wax layer on the outer surface. once immature, they're green. once mature, they need a brown to yellow or cherry color, and generally weigh three hundred to 330 mg per dried coffee. nonvolatilizable and volatile compounds in green coffee beans, like caffein, deter several insects and animals from consumption them. Further, each nonvolatilizable and volatile compounds contribute to the flavour of the coffee bean once it's roast. nonvolatile element compounds (including alkaloids, trigonelline, proteins and free amino acids) and carbohydrates ar of major importance in manufacturing the total aroma of cooked coffee, and for its biological action. Since the middle 2000s green coffee extract has been sold  as a nutritionary supplement, and has been clinically studied for its chlorogenic acid content and for its lipolytic and weight-loss properties.

The dose of green coffee extract:
Currently, the Most of the nutritional supplement company recommends 1000mg per day to 1600mg. On the TV show Dr. OZ recommends 800mg / twice daily (1600mg), On packing a supplement recommended 400mg / 3 times a day (1200mg). Essentially the recommended dose between 1000 - 1600mg, do not exceed them. Every time you buy a body slimming supplement carefully read the manufacturer's instructions. What else to look for when evaluating a Green coffee bean extract? Make sure that the supplement was manufactured in a country with proper quality controls.