Male growing breast with a cream call Naturaful. Is the growth reversable if I decide to stop or will they keep growing?

No OTC medicine increases breast size in Men ! Stay away from supplements that claim that they can do this- it is a scam. If it worked it would have been tested and FDA approved for this usage. 

Well, I believe that if you are seeing results you should continue until you reach your desired size. If tissues are truly grown, they will remain, but will also respond to the loss of whatever stimulated their development, just as natural breasts after pregnancy and/or breast feeding.Herbal creams or phytoestrogen-containing "natural" products may have unpredictable and variable effects on individuals using them, but if these were credible products that really worked for a majority of users, then plastic surgeons would be out of the breast augmentation business. Just because the company sells a product and has a slick website does not make it real. Yet you seem sold on the product, and that is good for you!You should understand that photographs can be "doctored," fake testimonials generated, and even a few "real" responders such as you might be induced to endorse a product that has no scientific validity, peer-reviewed credibility, and standardized photographic documentation. So, if it seems to good to be true, it usually is. If you think it really works, God bless you; I hope it continues to fulfill your expectations as it drains your wallet. No harm trying (in most cases--be careful of non-pharmaceutical hormone sources).The statements in the Naturaful website have not been evaluated by the Food and Drug
Administration. The product is not intended to diagnose, treat or
prevent any disease. The FDA does not evaluate or test herbs. Those two statement should tell you something as well. Best wishes and let us know how this works out long term, please! Dr. Tholen

I am surprised to hear that this product is helping you.  I have no idea if it is reversible as I doubt the cream is actually doing this.