Vitamins company NBTY, Inc. has entered into an agreement to acquire Dr. Organic, a naturally inspired skin care line in the UK. The deal is subject to customary closing conditions, and is expected to close later this year.   The Dr. Organic brand, which was first sold exclusively at NBTY's Holland & Barrett retail chain in the UK, experienced rapid success and was brought to the US in 2013 under the Organic Doctor name. In the US, Organic Doctor is sold exclusively through NBTY's...