In this article
Walk through any British park on a Saturday morning and you will probably pass a Cockapoo, a Cavapoo or a Labradoodle. In 2019 the Cockapoo was the second most popular breed among UK dogs under a year old, according to the researchers behind a 2024 study of these crosses1. Ask their owners why they chose a cross and many will mention health: mix two breeds, the thinking goes, and you get a sturdier dog.
That belief is a major reason people buy these crosses, and the idea behind it has a name: hybrid vigour1. But when researchers have put it to the test, the answer has come back more interesting than yes or no.
The short answer is not automatically. Here is what the research found, and what to check instead.
Where the hybrid vigour idea comes from
Hybrid vigour is the idea that a cross between two different breeds does better on some trait than the average of its parent breeds1. Guide dog breeders use crosses on purpose: guide dogs are commonly Golden Retriever and Labrador crosses, bred to keep useful traits while diluting some health problems1.
The idea has a real genetic basis. Most of the disease variants on one large genetic test panel are recessive7, so a dog usually shows the disease only when it carries two copies, one from each parent1. Pedigree breeds are closed gene pools, because a dog can only be registered if both its parents were3, so matching copies meet more often. As a group, purebred dogs are more likely than mixed breeds to carry two copies of a common recessive disease variant7.
The doodle boom also owes something to marketing. The trend is widely traced to Australia in 1980, when a man working for a guide dog association crossed a Labrador with a Poodle, then found homes for the rest of the litter with a catchy new name and a story of hybrid vigour that had little evidence behind it1.
The doodle study: 9,402 dogs compared
A direct test came in 2024, from researchers at the Royal Veterinary College. They surveyed UK owners of Cockapoos, Cavapoos and Labradoodles, and of the four parent breeds: Cocker Spaniels, Cavalier King Charles Spaniels, Labradors and Poodles1. The team compared the odds of the 57 most common disorders between each cross and each of its two parent breeds, 342 comparisons in all1.
The doodle study in numbers
So the crosses came out about as healthy as their parents: better at a few things, worse at a few, and the same at most. The authors found little support for hybrid vigour in these three crosses1. Nor did the results back the opposite belief, that dogs bred outside pedigree lines are bound to be less healthy1. Where they did differ, gains and losses fell in different places.
| Cross | Less likely than a parent | More likely than a parent |
|---|---|---|
| Cockapoo | Eye problems (both parents), slipping kneecaps (Poodle) | Itchy skin and being sick (both parents), ear infections (Cocker Spaniel) |
| Labradoodle | Hip or elbow dysplasia (Labrador), slipping kneecaps (Poodle) | Ear infections (Labrador), sickness and diarrhoea (Poodle) |
| Cavapoo | Eye problems (both parents), ear infections (Poodle) | Sickness and diarrhoea (both parents), ear infections (Cavalier) |
Ears are the pattern worth knowing. All three crosses had higher odds of ear infections than their non-Poodle parent, though not compared with Poodles. Poodle-type and spaniel-type breeds were already known to be prone to them, partly because of droopy ears and hairy ear canals1.
There are limits. The reports came from owners, not vet records, and owners who chose to reply may be more welfare-minded than most. Because every dog was under five, how these crosses fare in later life is still unclear1.
Do crossbreeds live longer? Two big studies disagree
Lifespan is where the evidence pulls in two directions. A 2013 study of vet records for 102,609 dogs in England, including 5,095 that had died, found a median lifespan of 12.0 years. In the researchers' statistical model, crossbreeds lived 1.2 years longer than purebreds, and they took that as support for hybrid vigour2.
A 2024 study led by Dogs Trust pooled records for 584,734 UK dogs from 18 organisations, including breed registries, charities, insurers and vet groups. This time purebreds came out slightly ahead, with a median of 12.7 years against 12.0 for crossbreeds3. Of 155 breeds, 47.1% had a longer median lifespan than the crossbreed group, 25.8% a shorter one, and 27.1% did not differ significantly3.
Why the difference? The 2024 team point to limits in their data: the crossbreed group mixed first crosses with dogs of unknown ancestry3. Breed registries also supplied 45% of the records, which the authors say probably tilts the data towards pedigree dogs3. They did not rule out hybrid vigour, noting that mixed breeds have been reported to live 1.2 years longer than purebreds of the same size3.
Both studies point to bigger influences on lifespan. Larger dogs had shorter lives in each3, 2. In the 2024 data, flat-faced purebreds had a median of 11.2 years against 12.8 for breeds with medium-length faces, and breed medians ran from 5.4 years for the Caucasian Shepherd Dog to 15.4 for the Lancashire Heeler3. That spread dwarfs the pedigree-crossbreed gap, whichever way it falls.
It depends on the disease and the parents
Health is not one thing. A US study of medical records for 27,254 dogs with inherited disorders compared 24 conditions in purebred and mixed-breed dogs. Thirteen showed no difference between the groups, including hip dysplasia, slipping kneecaps and the cancers studied. Ten were more common in purebreds, among them elbow dysplasia and cataracts. One, cruciate ligament rupture, was more common in mixed breeds8.
The researchers suggested that conditions found as often in both groups stem from ancient mutations spread widely through the dog population8. Genetic testing agrees. A study by the scientists of one commercial testing lab looked at more than a million dogs, most of them mixed breeds: 57% carried at least one copy of a disease variant on the lab's panel, and nearly nine in ten of the variants found turned up in both mixed-breed and purebred dogs7.
A cross can also inherit what both parent breeds share. Cockapoos and Labradoodles were less prone to slipping kneecaps than Poodles, but Cavapoos were not: Cavaliers and toy breeds such as the Toy Poodle are both prone to the problem, and 41.5% of the Cavapoos had a Toy Poodle parent1.
Nor are mixed breeds safe from inbreeding. In both groups, dogs with less genetic variety tended to carry more disease variants in double copies, and close relatives are bred together in places such as puppy farms7. Any gain from crossing is expected to be biggest in a first cross, fading as later generations grow more inbred1, 3.
Where crossing clearly helps: body shape
The clearest case for crossing comes from flat-faced breeds. In a 2026 UK study, a vet examined 51 Pugs and 99 Pug crosses: Jugs (Jack Russell and Pug) and Puggles (Beagle and Pug)4. None of the 48 Pugs assessed for breathing (three had already had airway surgery) was graded as normal on a standard breathing assessment, against 98 of the 99 crosses, and the Pugs also had more eye, skin, joint and muscle problems4.
The crosses had longer muzzles and more open nostrils. Their owners put vet bills at a median of about £10 a month, against £41.67 for the Pugs, and the dogs' behaviour and bond with their owners were much the same4. Most were first crosses, and the authors caution that later generations may be more variable4.
What matters more than the label
If you are choosing a puppy, cross or pedigree, the parents tell you more than the name. The health screening schemes set up by the British Veterinary Association and the Royal Kennel Club cover inherited hip, elbow and eye conditions, among others, and are open to crossbreeds as well as pedigrees5. The BVA advises buyers to always ask to see the relevant test results for both parents5.
How a puppy is bred and sold matters too. A UK study that followed 985 puppies bought in 2020 found that those sold without the buyer seeing the mother were more likely to have more health problems by 21 months6. Being purebred was also linked with more problems, as one factor among several. More surprisingly, so was the owner having seen the parents' health test results6. The paper does not explain that link, and it does not make testing pointless: the authors say the schemes can reduce the particular conditions they screen for6.
Questions to ask about a puppy's parents
- Which health tests have both parents had, and can I see the results?5
- Do those tests cover the problems most common in both parent breeds?6
- Is the puppy a first cross, and are the parents related to each other?1, 7
- If a flat-faced breed is involved, is the other parent a breed with a longer muzzle and open nostrils?4
- Can I see the puppy with its mother?6
When to talk to your vet
If you already have a cross or a pedigree, none of this changes how you care for them. It does give you a question for your next check-up: which problems are common in your dog's parent breeds, and what should you watch for? With a Cockapoo, Cavapoo or Labradoodle, ears, skin and tummies are a sensible place to start1.
If you are still choosing, talk to a vet before you fall for a face. They can tell you which problems run in the breeds behind a cross, and which health tests to ask a breeder about.
Next time someone at the park gate tells you crossbreeds are healthier, you can say it depends on the parents. That is true of every puppy, and it is the part you can check before you bring one home.
Sources and further reading8 sources
The small numbers in the article link to the source behind each fact. Sources open on their own websites.
- The doodle dilemma: How the physical health of 'Designer-crossbreed' Cockapoo, Labradoodle and Cavapoo dogs' compares to their purebred…
- Longevity and mortality of owned dogs in England
- Longevity of companion dog breeds: those at risk from early death
- A solution right under our nose? Crossbreeding extreme brachycephalic dogs results in better health outcomes while preserving behavioural…
- Canine Health Schemes
- Sold a pup? Impact of purchasing practices, owner and dog demographics, and puppy early-life experiences on later canine health outcomes…
- Genetic prevalence and clinical relevance of canine Mendelian disease variants in over one million dogs
- Prevalence of inherited disorders among mixed-breed and purebred dogs: 27,254 cases (1995–2010)