Watermelon is fine, a good summer treat cold. I freeze the bannanas, great for puppies cuttiing teeth, old dogs love it on a hot day. Avacado meat is finew, it's the skin, branches & leaves that are the problem. I've been feeding all three for 2 1/2 years to my Rotty with no problems. Her OFA thyroid blood work just came back normal. Avacado is rich in omega fatty oils and is a good complement to fish oil. Watermelon? look here ---> http://home.howstuffworks.com/watermelon3.htm