If I were to survey my patients’ refrigerators, odds are I’d find milk in almost all of them. With the exception of those with a diagnosed medical problem related to dairy consumption, just about every parent reports that their kids drink at least some milk. I commonly pass along the recommendation that children have 2-3 cups of dairy during the day, and my own kids certainly put away their share of it.

PETA (People for the Ethical Treatment of Animals) is trying to scare people into changing all that.

As recently reported by The Daily Beast, PETA has launched a campaign that tries to link milk consumption and autism. With an increasing number of autism cases being diagnosed year after year, the organization has decided to rejuvenate an old and controversial “Got Autism?” ad that suggests dairy may play a role, despite a decades-long trend of declining milk intake in the United States [pdf].

It seems that PETA was unhappy to have had its revamped campaign debunked. In an email sent to The Daily Beast defending “Got Autism?” their media liaison, Jordan Uhl, wrote, “PETA’s website and campaign serve to provide parents with potentially valuable information that has been backed up by researchers and many families’ findings.”

But PETA’s claims aren’t just limited to blaming milk for exacerbating symptoms in autistic children. According to the website associated with their campaign, “The reason why dairy foods may worsen or even cause autism is being debated.” Further down the page it says, “Anyone who wants to alleviate the effects of autism should give cow’s milk the boot and switch to healthy vegan alternatives instead.” PETA isn’t just saying that some autistic children may benefit from an exclusion diet—it’s blaming dairy for the disorder itself.

Uhl’s email included a letter in support from Gillian Loughran, editor of Autism Eye, a British publication devoted to issues relating to the disorder. In her letter, Loughran wrote, “From a very young age, my son, who has autism, has been on a casein-free, gluten-free diet. It's quite common within the autism community, and numerous parents are making this switch.”

Regarding her own publication, she continued, “[W]e have covered the link between consuming dairy products and the symptoms of autism. We don't give our readers medical advice because we are not doctors, but we certainly give parents information about what is reported to be working for other people and then let them and their doctors determine whether it helps their child.”

Perusing the Autism Eye website, one can find articles in support of such diets. Unfortunately, one can also find dubious information about toxins (those conveniently vague autism culprits and basis of many sham treatments) and other articles implying a link between the MMR vaccine and the disorder.

Loughran’s support is a mixed blessing from a scientific point of view.

However, when contacted directly about PETA’s campaign, she reiterated her reluctance to offer a medical opinion about the causes of autism. Responding to a follow-up email, she replied, “Not being medically trained, we are not in a position to make [dairy exclusion] recommendations to parents.” She alluded to research on the topic, but did not provide any herself.

So where is the research PETA’s Uhl says they have in support of their “Got Autism?” campaign? How do they maintain their claim that milk actually causes autism? When I responded to his email, I was directed to Heather Carlson, PETA’s communications manager.

In a message to me, Carlson wrote, “The content on our website and blog is really the extent of the campaign. There are a lot of reasons not to give children cow’s milk, and since some parents of children with autism are sure that aggravation of symptoms is one of them, we added information to our website so that people can consider it.”

That’s the extent of the campaign? A couple of inflammatory, fear-mongering insinuations on their website constitutes information worth considering, in the hopes that everyone who reads it buys them unquestioningly?

When pressed for sources to support their specific assertion that dairy plays a causative role in developing autism, she wrote in another message, “Until a large study (one we hope will not be funded by the dairy industry) is conducted into whether there is a link between autism and the consumption of dairy products, it seems unwise to overlook a growing body of anecdotal evidence that removing dairy products and gluten from an autistic child's diet may improve his or her sleep, behavior, and concentration. Research is badly needed.”

I’m not sure how credulous Carlson thinks I am, but when asked for the information “backed up by researchers” that her colleague mentioned, she was able to provide none. Her media relations doublespeak is a wispy tissue attempting to cover up a yawning evidentiary chasm, and gesturing vaguely toward anecdotes is a parody of verification. PETA is clearly taking public concern about a complex medical problem with an unclear cause, and attempting to parlay it into a smear campaign against an industry it plainly despises.

Do I have a few autistic patients whose parents report a benefit from giving them a dairy-free diet? Yes, though it bears mentioning that none have purported anything near to an actual cure. So long as their diets contain other good sources of protein and calcium, I don’t try to talk their parents out of it. But even supposing that these benefits are genuine, that’s hardly a sufficient basis to tell other parents that dairy products contribute to developing the disorder in the first place. Plenty of my asthmatic patients benefit from living in houses without cats, but I don’t tell parents whose children lack the disease to ship their pets off to the pound to prevent them from getting it.

Animal welfare is an important issue, and one that deserves due scrutiny. PETA’s grievances with the dairy industry may well have merit. But attempts to leverage the public’s worry about autism in support of their unrelated goals delegitimize their entire organization. The claims of their “Got Autism?” campaign range from tenuous to unambiguously false, and their ill-considered attempts at defending them merely make more obvious their shameful distortion of the truth.