Dog drinking and urinating more

Question
Hello, I have a 1 yr 5 month old male 40 lb terrier mix. He is neutered, perfect weight (not overweight or under), up to date on all vaccines (distemper combo, rabies, bordatella), and receives monthly flea and heartworm preventative. I am not sure if he has been drinking or urinating more lately or if I have simply been noticing it more but it seems to be slightly more than he has in previous times. For the past few weeks he has been drinking, what seems to be, more and the result is urinating more. He is very healthy and SUPER active, he is a hyper terrier. He is almost like a 40 lbs jack russel so I know he is feeling just fine because that is his normal temperament. He has NO other symptoms other than drinking a bit more which leads to urinating a bit more. My concern is that I read alot about drinking and urinating more as being signs of diabetes but he is very healthy and maintains a healthy 40 lbs and is very active. The symptoms I read include things like losing weight, vomiting, or acting sick, which he has never done. I have had him since he was 8 weeks so I know exactly what is normal for him in terms of his activity level and he has never acted sick. He has always been a very strong, active, hyper dog. My questions are: how much is normal for a VERY active 40 lbs dog to drink and urinate? If this is beginning diabetes, would there be other signs? Does a little more drinking and urinating warrent a vet visit? I have read a bit about diabetes and he has none of the signs except the drinking but that seems to be the beginning, should I be concerned? He is my pride and joy and has always been very healthy and I have been sure to give him the exercise he needs and feed him a balanced, quality diet so he stays healthy. It seems odd to me that a dog who is so healthy and active would have diabetes but then again I know it can be genetic. I cannot rush him into the vet everytime I "think" he is drinking more or urinating more due to my finances so I want to learn a bit more about the change and see if it it something I should seek attention now for or if I should keep an eye on it. Any comments? Thanks for your help.

Answer
I wouldn't jump to the conclusion right off the bat that he has diabetes Rachel. While it is a common disease, the symptoms are as you said plus the water consumption is nearly continuous. I mean they are at the water bowl all the time.

Diet plays a part in water consumption. What you feed, the quality of the food and the amount of sodium in it also contribute. Whether or not the food is the same each time has a bearing. Most pet foods are made with open formulation so that the ingredients are not the same with each batch, even if the content reads the same.

Now 40 lbs is large for a terrier unless the other part of him is lab or something. A jack Russell male shouldn't be more than 20 lbs tops. A mixed terrier of course can weigh more if they are crossed with something larger. I mention this because there is a chance that he is a bit overweight.

Here is a chart that can help you determine what your dogs physical shape should be.
http://www.peteducation.com/article_print.cfm?c=2+2099&aid=661

I am sure he is in good shape- from your description and his age he sounds in good health.
There are other things that can cause excessive urination. You need to be aware of these also.
Some are bladder stones, kidney stones, kidney disease, dehydration, and as you said, diabetes, specifically, diabetes insipidus, which is an unexplained diabetes that is not pancreas related.

Diabetes mellitus is the more common form of diabetes and is usually age onset. This is when the pancreas is having problems with the sugar in the bloodstream.  

If his water intake continues to increase a thorough exam by your vet is in order. That includes xrays for bladder stones and blood work for everything else.

So monitor the amount he drinks by measuring it out and keeping a chart. Get him on a good, fixed formulated diet. Hill's Science Diet is the only one on the market today that has fixed formulation. Get him on that and he will live a long, healthy life.

Take the three bag challenge and watch him change in three weeks!
http://www.feedingisbelieving.com/believe/3-Bag-Challenge-Form.html

Please let me know what you find out and how he does. Thanks for being a caring and responsible pet owner!