In petsmart today a girl had a 7 year old golden retriever. He seem to be extremely, extremely, extremely obese. This dog outweighed me any day and i am 156lbs. Very wide he got around fine though no problems there was happy as could be so i aproach her and asked if i could pet him she said yes, he was a sweet dog. I aksed her why he was so big, i have seen some fat dogs in my day but nothing this size, and she said he had a thyroid problem. Does that make dogs that large? I also thought there was medicine for it?