# Larger breeds of dogs have shorter lifespans. . . **URL:** \ **Category:** Factual Questions\ **Created:** [June 3, 2005, 8:37pm UTC](https://boards.straightdope.com/t/larger-breeds-of-dogs-have-shorter-lifespans/306781 "2005-06-03T20:37:15Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Earl\_Snake-Hips\_Tucker](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/earl_snake-hips_tucker/32/3269_2.png) [@Earl\_Snake-Hips\_Tucker](https://boards.straightdope.com/u/Earl_Snake-Hips_Tucker)\ **Post date:** [June 3, 2005, 8:37pm UTC](https://boards.straightdope.com/t/larger-breeds-of-dogs-have-shorter-lifespans/306781/1 "2005-06-03T20:37:15Z")
Or do they? Is there any scientific evidence to show there’s a correlation between size (of members withing a particular species) and longeivity? I’ve heard the same thing about horses, but it’s alway anecdotal. ---
**Author:** ![alice\_in\_wonderland](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alice_in_wonderland/32/176_2.png) [@alice\_in\_wonderland](https://boards.straightdope.com/u/alice_in_wonderland)\ **Post date:** [June 3, 2005, 8:39pm UTC](https://boards.straightdope.com/t/larger-breeds-of-dogs-have-shorter-lifespans/306781/2 "2005-06-03T20:39:49Z")
Well, my vet agrees with it - he sais 10-11 years for a large dog is considered decent, where as 13-15 for a small dog is the norm. Sadly, I don’t know where he got this info. ---
**Author:** ![PinkMarabou](https://avatars.discourse-cdn.com/v4/letter/p/ec9cab/32.png) [@PinkMarabou](https://boards.straightdope.com/u/PinkMarabou)\ **Post date:** [June 3, 2005, 8:55pm UTC](https://boards.straightdope.com/t/larger-breeds-of-dogs-have-shorter-lifespans/306781/3 "2005-06-03T20:55:54Z")
I wish I had a cite for you, but I don’t. The last time I was in the vet’s office, there was a poster on the wall so you could equate how old your dog is in “dog years”. The smaller dogs aged faster earlier, yet the bigger dogs caught up after a year or so and surpassed the smaller breeds. Of course, barring any genetical issues and that you’re a good pet owner, dogs can live to somewhere around 10-16 or so years. Most dogs I’ve had on average lived to about 13. I also heard that mutts live longer because they are not predisposed to inbreeding. Whether or not this is true, I have no idea. But since I saw the breed size chart in the vet’s office, I would surmise this to be fairly close to true. I have a wonderful vet (the best in Ohio, IMO) and I would hope he wouldn’t post something to be untrue. But the science world is always changing, so who knows what it will be 5 years from now. ---
**Author:** ![JerH](https://avatars.discourse-cdn.com/v4/letter/j/bb73d2/32.png) [@JerH](https://boards.straightdope.com/u/JerH)\ **Post date:** [June 3, 2005, 8:56pm UTC](https://boards.straightdope.com/t/larger-breeds-of-dogs-have-shorter-lifespans/306781/4 "2005-06-03T20:56:41Z")
If you Google a bit, you can find a few sites listing life expectancy by breed, but none of them list their sources. Of the lists I found, it looks like the “smaller = longer life span” is generally true, but it’s not a linear progression. For example, according to [one site](http://www.pets.ca/pettips/tips-46.htm), bulldogs seem to have the shortest life expectancy (6.7 years), but are certainly smaller than Great Danes (8.4) or mastiffs (8.6). I suspect that size is a large factor, but particular breed’s tendency toward certain ailments (bulldogs are prone to respiratory ailments, IIRC) are just as much of a factor. ---
**Author:** ![Pullet](https://avatars.discourse-cdn.com/v4/letter/p/edb3f5/32.png) [@Pullet](https://boards.straightdope.com/u/Pullet)\ **Post date:** [June 3, 2005, 9:08pm UTC](https://boards.straightdope.com/t/larger-breeds-of-dogs-have-shorter-lifespans/306781/5 "2005-06-03T21:08:01Z")
I don’t know if anyone has really done a hard study on this. It’s so difficult to control for environmental factors. But yes, speaking as someone who has worked in the Veterinary industry for a while, small breed dogs tend to live longer than large breed dogs. But, like any trend, you’ll find cases where it’s true and cases where it isn’t. Also, to nitpick **PinkMarabou** slightly, mutts live longer because they are not inbred, not because the are indesposed to inbreeding. Inbreeding increases the chances that a bad genetic trait will be displayed. Mutts, by drawing off of a very diverse genetic pool, are less likely to have regressive, detrimental congenital diseases. Once again, oesn’t mean it never happens, though.