Children of pregnant vegetarians more likely to abuse drugs and alcohol

Woman Slumped On Sofa With Drug Paraphernalia In Foreground

I am not making this up.

STAT News reports:

Children of women who ate little or no meat while pregnant are more likely to abuse alcohol, tobacco, and marijuana at age 15 than are children of mothers who did eat meat.

That’s the conclusion from a new study Meat Consumption During Pregnancy and Substance Misuse Among Adolescent Offspring: Stratification of TCN2 Genetic Variants published in Alcoholism Clinical and Experimental Research.

Until a result is reproduced, it ought to be viewed as interesting, but speculative and unproven.

How was the study performed? According to STAT News:

Researchers analyzed data from 5,109 women and their children in a long-running study in England called ALSPAC (the Avon Longitudinal Study of Parents and Children), which has gathered years of data on what women did while pregnant and their children’s health. The less meat the women ate while pregnant, the more their children’s risk of drinking, smoking, or using marijuana as 15-year olds, Dr. Joseph Hibbeln of the National Institute on Alcohol Abuse and Alcoholism of the National Institutes of Health and his colleagues reported on Wednesday in Alcoholism: Clinical and Experimental Research. (They were funded by the U.S. and U.K. governments and a charity, not meat producers.)

Roughly 10 percent of the 15-year-olds smoked at least weekly, drank enough to have behavioral problems, or used marijuana “moderately.” But teens of meatless moms were 75 percent more likely to have alcohol-related problems, 85 percent more likely to smoke, and 2.7 times as likely to use marijuana compared to teens of mothers who’d eaten meat while pregnant.

Children of pregnant vegetarians are more likely to abuse drugs and alcohol.

Ironic, isn’t it, that a diet thought by its practitioners to be healthier is actually harmful to developing babies?

Ironic … and almost certainly untrue.

This research represents a cautionary tale, not about the risks of vegetarianism, but about the risks of p-hacking, a practice beloved of some scientists, particularly those in the field of breastfeeding research.

P-hacking often occurs in the analysis of large data sets. It refers to the value “p” used to determine statistical significance. A difference between two groups is only meaningful if it is statistically significant, expressed as the chance that the findings are due to chance. For example, a p value less than 0.001 means that there is a less than a 0.1% chance that an observed finding is due to chance and a greater than 99% chance that it represents a real difference.

Researchers look for statistically significant differences between two groups. Then they announce them as “findings” without acknowledging that any large dataset looking at multiple outcomes is bound to have random statistically significant differences that are coincidental and don’t represent real outcomes. Indeed, by definition using a p value of less than 0.001 means that almost 0.1% of the differences that appears to be statistically significant are actually due to chance and don’t represent a real finding at all.

When looking at studies of a few variables, a p value of 0.001 means that a statistically significant results is almost certainly a real result. However, mining of large datasets may involve thousands of variables. For example, in mining a dataset of 10,000 possible variables, we would expect that 0.1% — 10 statistically significant results — are, by definition, actually due to chance, and therefore, not real.

How can we guard against p-hacking? The most important way is to recognize that it is always a possibility when analyzing large datasets; in other words, it is wrong to conclude that every statistically significant result in such an analysis is a real result.

In addition, there are a number of additional statistical tests that can give greater insight into whether a result is real or just a statistical artifact.

The ultimate insurance that a result is real and not an effect of p-hacking is a basic principle of all research: reproducibility. Do other data sets produce the same results? Unless and until the finding is reproduced, there is no reason to believe that the results are real.

Therefore, we should not be rushing to counsel pregnant women that vegetarianism leads to substance abuse among offspring. It almost certainly does not. The finding is most likely spurious, just an artifact of the statistical analysis.

This cautionary tale has implications far beyond this study, most especially in breastfeeding research. Many of the purported claims about the benefits of breastfeeding are also based on mining of large datasets. Such studies by definition will produce spurious statistically significant relationships. When such a “benefit” is discovered in breastfeeding research, it should be greeted with the exact same skepticism that ought to greet this study.

A good rule of thumb is this: Until a result is reproduced, it ought to be viewed as interesting, but speculative and  unproven.

  • Platos_Redhaired_Stepchild

    I bet you its rebellion. My mother was a crunchy ( although meat eating ) mother. I rebelled with by eating all the junk food I was forbidden to touch when I was a kid. I bet you these kids got “body purity” crammed down their throats until they hated it and ran into the toxic arms of sugar, meat, booze, & drugs.

  • Amazed

    OT: A few hours ago, I was talking to the Intruder by the phone. The moment he said, “Sis”, Amazing Niece started yelling, “Auntie! Auntie!” Looks she can already make the logical connections that Auntie is Daddy’s sis. Then, they put me on a loudspeaker and my SIL started making a video. Kid’s running all around the room looking for me and shouting, “Auntie!”, grinning and showing all her teeth. Then, when the loudspeaker was turned off, she cuddled up to her father to listen to my voice. And when he asked, “How are you now? Still in low spirits?”, she started hugging the air, repeating, “Hug, hug, Auntie.” I sang the song that only I do and she was happy.

    Clearly, she’s a very insecure child who will never be able to feel true love for people in her life because she has not spent her entire life this far on her mom’s hip. Really, how could she ever be happy and sunny?

    Are the hardcore AP right in the head?

  • Claire Risley

    as a statistician, no, this isn’t p hacking. for a start they found the effect with all substances tested (unless they left some out which seems unlikely as all major ones are here), and secondly the greater the genetic deficiency in B12 absorption, the greater the effect – i.e. there’s a biological gradient (https://en.wikipedia.org/wiki/Bradford_Hill_criteria). The problem with this study is the emphasis on vegetarianism not B12 deficiency. It’s a clear demonstration all pregnant mothers should supplement with b12 whether veggie or not.

    • Sheven

      While I’m willing to believe the results, to me it seems to be a stretch to believe that a b12 deficiency could lead to such complicated behavior a decade and a half later. For lack of a better word, it trips a “bullshit” alarm.

      I’m not saying that my sense of disbelief overrides the numbers, but I am interested in knowing if, as a statistician, you ever have the same sense. “The data adds up, but this doesn’t seem right.” Or perhaps you have experience with the opposite effect. Seemingly “bullshit” data that does bear out in the real world, even if it doesn’t seem credible at first sight?

    • swbarnes2

      This line didn’t make much sense to me:

      “Lower meat consumption disproportionally increased the risks of offspring substance misuse among mothers with optimally functional (homozygous) variants (rs1801198) of the gene TCN2 which encodes the vitamin B12 transport protein transcobalamin 2 implicating a causal role for cobalamin deficits. ”

      So the effect was strongest when the mother had a fully working version of the gene?

    • Toni35

      Could there have been a saturated fat and/or cholesterol deficiency? I know those nutrients have been demonized over the past 2-3 generations, and they can be hard to come by in a veggie diet. Did the study look at that angle at all?

      Just curious.

  • Empress of the Iguana People

    yeah, this is the kind of result that makes me -highly- skeptical of its accuracy.

  • Dom

    Ahh another thing to scare mothers with. I couldn’t eat any meat while pregnant, my aversion was so bad it couldn’t even be in my fridge. I know I’m not the only one too! What if it isn’t the lack of meat, but the cause of these aversion?

    • Azuran

      Or you know, maybe those kids are just rebelling against their parent’s lifestyle :p

      • maidmarian555

        We often joke that once our kids hit their teens and that rebellious stage, we’re going to have a pair of straightedge Vegans for Jesus on our hands……

  • nohika

    Like. Yes, as someone who has their Masters with a statistics specialty, I understand where you’re coming from. But…do you know how difficult it is to get reproductions of something published?? It almost never happens. Journals don’t care to publish anything that’s been done already. Not that it shouldn’t be a thing, but that’s why it’s generally not a thing.

    And while p-hacking is a thing, I’d be curious to know more about the actual dataset (and data collection) before any assumptions were made about what the researchers may or may not be doing.

    • Young CC Prof

      Whether or not the results are sound, IMHO, depends partly on what they were looking for. If the original goal of the study was to see what effect meat consumption in pregnancy has on adolescent drug use, the findings could be fairly robust, although confounders are certainly possible, as noted below. Could be socioeconomic status, and I wonder whether vegetarians are more likely to used marijuana or to know people who use it.

      However, if they went through a large dataset, looking for basically any connections between pregnancy diet and offspring health, or even between meat consumption and offspring health, the findings are best explained by coincidence.

      In the absence of any other information, I’m going to fall back on the Internet’s favorite study rebuttal, a personal anecdote: My mother has been vegetarian since 10 years before my conception, and I never used drugs in high school. Therefore, the study MUST be wrong!

      • Roadstergal

        I mean, ideally you do it in the same paper. Training dataset, test dataset. Ideally. :p

        Pre-specified analyses are nice…

      • Sarah

        My mum has never been a vegetarian and I did!

  • Clarene Wong

    nutritional yeast is a gateway drug

  • MaineJen

    Um. Just off the top of my head. Women who are better off financially would be more likely to eat vegetarian, right? They are the ones who get to pick and choose the “best”, healthiest foods. (Correct me if I’m wrong). And rich kids have an easier time getting their hands on pot and alcohol, I imagine. Just a little confounder to go with your morning coffee.

    • J.B.

      Also maybe some type A perfect and anxious mom confounders. Maybe someone could do a study on the teenaged kids of AP moms?

    • Petticoat Philosopher

      Poor kids get their hands on pot and alcohol plenty, trust me. It’s just cheap 40s, not good stuff. I don’t really know what this correlation is all about, but I’m curious.

    • AnnaPDE

      Also, the type of hippie parent whose kid might be into marijuana without getting in trouble is also more likely to go vegetarian.

      • Hannah

        Dude, I know it’s an unpopular view but vegetarianiam really isn’t a hippie thing any more. In fact it’s more in line with most progressive scientific thinking. My reasons for not eating meat come from the same place as my hatred of ideology led anti science bs. Most people think it’s only needed in their diet due to tradition and culture after all..

        • AnnaPDE

          Dudette, I’m not saying that vegetarians are hippies. But that hippies – people who question rules about drugs and society etc – are likely to be vegetarian.

          • Hannah

            I know, it’s one of those unhelpful stereotypes I just wish would die already y’know?

          • AnnaPDE

            I totally get it. There are all these jokes about vegetarians and especially vegans constantly having to talk about their diet, but in practice somehow it’s usually some omnivore who can’t let go of the topic or stop proselytising once they find out someone doesn’t eat meat.

        • A heavily plant-based diet is in tune with modern scientific thinking. A fully plant-based diet is not. It’s not wrong, but it’s also not right. I know for me personally, not eating meat at all is bad for me. My family tends towards anemia, and the iron in red meat is very important for staving that off.

          Meat is an important source of a lot of nutrients. A vegetarian diet is absolutely capable of providing those nutrients, but it takes a lot of time and effort to make sure you’re not missing anything. Please stop painting yourself as better than everyone else due to your personal dietary choices.

          • Hannah

            Huh? I don’t think I’m better at all. I do think the the stereotype of vegetarians is inaccurate though and it’s not great to know that people make all kinds of crazy assumptions about you because you happen not to eat meat.

          • Fair enough. I might have misread “more in line with most progressive scientific thinking” as being self-congratulatory when it wasn’t meant that way at all. Text communication is like that :/. Sorry for misreading it.

  • Zornorph

    Hitler was a vegetarian. Just saying.

    • StephanieJR

      Is there no low to which that man didn’t stoop? /s

      • Azuran

        I think he also loved puppies, so now you can’t love puppies anymore.

        • Charybdis

          No, I’m sorry. I currently do and will continue to love puppies no matter who else does (or did).

          So there! 😛

        • Zornorph

          Perhaps, but he also poisoned his dog, so that counts against him.

    • CSN0116

      So is Brooke. So…

      • BeatriceC

        And I just nearly shot iced tea out of my nose.

        • Hopefully the ice cubes had melted first…

          Sometimes being exposed to a certain lifestyle does have a paradoxical effect — both my parents were heavy smokers and I have never been the least interested in smoking, and find the very smell of stale smoke nauseating. Due to her 3 pack a day habit, my Mother had no appetite and we were served frozen TV dinners for years. That drove me, in high school, to learn to cook excellently, with the result that my own daughters had no interest in eating anything but Ima’s food until they themselves married and were forced into the kitchen for their own families!

          • BeatriceC

            Cooking…here is another example of things my mother did right. In spite of all the awful, there are a few good things. My mother is a great cook and was very patient in teaching us kids how to cook ourselves. It was the one room of the house we could destroy with “experiments” and not get into any trouble, assuming we cleaned up our messes afterwards, which we pretty much always did. Unfortunately, while my boys won’t ever starve to death, to don’t have anywhere near the skill in the kitchen my adult siblings and I did by their ages.

      • Spamamander, pro fun ruiner

        *slow clap*

    • Kim

      There’s a fascinating book by the German writer Norman Ohler called “Blitzed”, which is about the extent of drug-taking by the top Nazis. Hitler was a particularly enthusiastic consumer of hard drugs, most of which were made from animal products. So he may not have eaten much meat, but it certainly found its way into his body.

      • Roadstergal

        Ooh. Adding to my wish list.

  • CSN0116

    When I think of some of the papers I’ve had rejected and this was accepted for publication…

    • Hannah

      As a vegetarian who finds anti-veg sentiment to be second only to natural birth doctrine in terms of its idiocy, it doesn’t surprise me at all to see this sort of nonsense being lept on. Something about the pro meat lobby seems to activate a part of the brain that does not respond to logic, and I have often seen parallels between aggressive omnivores and the normal birth crowd!

      • Zornorph

        Sanguis bibimus
        Corpus edimus

      • Eh, a lot of early vegetarians were pretty evangelical about it, and there were a lot of Meat is Murder things running around for awhile. I’ve seen parallels the other way too- vegetarians or (especially) vegans compared to the natural birth crowd.

        This result is still complete and utter bullshit, of course. There’s nothing wrong with a healthy diet regardless of whether or not it includes meat. But seriously, don’t dis omnivores either!

        • Petticoat Philosopher

          I think that used to be more true than it is now. I have to say, most of the vegetarians and vegans that I know now are happy to just do their thing and manage to not be harassed by others about it. Of course, I also don’t hang out with assholes.

          • Oh for sure, it hasn’t been the case for a long time. It was always exaggerated anyways- though those people exist(ed), they were not the majority of vegetarians by any means.

          • Azuran

            It mostly moved online I think.
            I’ve only met 1 veg in person who was an ass about it. But online they are easy to find (as are every possible kind of assholes)

      • attitude devant

        Meh. I’ve got nothing against vegetarians. I live in an area where there are lots of vegetarian restaurants. I like plant food and I don’t eat much meat myself. Sure do hate being proselytized about it, though.

        • Hannah

          The article and “study” are doing the literal opposite of that though!

      • namaste

        I personally have zero fucks to give over what goes into anybody elses mouth but my own. I am personally an omnivore. Vegitarian? Vegan? strict carnivore? Knock yourself out, I say. I do however have a lot of very big fucks to give if someone is trying to push that choice onto me. I find it to be very violating. And really, that extends to “Diet culture” in all of its forms.

        • Kim

          But if you believe something is morally wrong, then of course you try and persuade other people of that. Nobody says, “Hey, I don’t believe in killing people, but if you do, be my guest.” If you genuinely believe that killing animals is cruel, then you want to stop it happening. Apart from which, there are very very good environmental reasons for ending or at least reducing meat production.

          • Poogles

            “But if you believe something is morally wrong, then of course you try and persuade other people of that.”

            Eh…I understand what you mean, but there are plenty of areas where it’s better to just mind your own business most of the time.
            Some things are considered morally wrong by pretty much the entire human race and have a direct, negative effect on other people (such as killing other people) and so to try and persuade people not to do those things makes sense.
            Other things are only considered morally wrong by certain, smaller, groups of humans and don’t really have any effect on other people – things like what types of food you decide to eat, or what clothes you decide to wear, or who you decide to have sex with and when – things like this, it is better to mind your own business, most of the time.

          • Kim Thomas (casual)

            If something’s morally wrong, it doesn’t really matter what the large majority of people think about it. Take abortion (and I’m pro choice). If you really believe that abortion is murder, then you wouldn’t just say, “Hey, i’m not going to have an abortion but I don’t mind if you do.” You’d want to stop everyone doing it, wouldn’t you? Ditto, for example, female genital mutilation. There are some cases where you can’t take a “live and let live” approach. And ethical issues aside, meat and dairy farming is a huge contributor to climate change, so if you believe climate change is a real thing, and want to stop it happening, you should really cut down on your meat and dairy consumption. It’s only going to make a difference if *lots* of people do it.

          • Kerlyssa

            it’s a matter of degree. if you equate animal killing with, saying, killing of human beings, your behavior is going to be pretty out of whack w accepted norms. there is only so far you can persuade people

          • namaste

            Vegans/vegetarians and omnivores are just going to have to agree to disagree on valuing animal life equally with human life. If you do, you are free to act on it as you see fit. However, proselytizing is just fucking annoying.

          • Heidi

            I don’t think most vegetarians or vegans value human life equally to other animal life. That’s a pretty extremist view.

      • Roadstergal

        Yeah, there’s definitely a case of folk who will a: try to talk you out of it and/or b: go over the top about how many animals they eat and how they’re going to have to eat more to make up for you.

        • Empress of the Iguana People

          My best friend went vegetarian in high school, mostly because she thinks meat is tasteless and veggies the bomb. Her mom did -not- understand that sausages and chicken are meat too.

          • Sarah

            ‘Could she have some wafer thin ham Barbara?’

            If you don’t know it, google it. Sums up that mindset perfectly!

        • Kerlyssa

          yeah, lotta asshole carnivores and vegans. most veg asshoels seem to be vegans these days- better bragging rights?

        • Heidi

          Yes. I was a vegetarian for a few years, and I can’t count the number of times some turd had to rationalize their meat-eating that I never questioned or chose to inform me how deficient in iron or protein I was gonna be (gave blood and always had high end of normal hemoglobins TYVM). I still don’t get how me choosing not to eat meat was a personal attack on anyone else, or how it qualified others to give me unwanted health advice. I figure some of the more extreme, vocal vegetarians/vegans got to be that way as a defense mechanism.

      • Azuran

        Might be because the most vocal of the veg groups are running around all over the internet calling all meat eaters murderers. I can’t read any article about farming without the comments being swarmed by rabbid vegans (and I have no doubt that the stupid aggressive carnivore are doing the same thing on any veg article/video)

        Both extreme are stupid. And sadly, the extremes in any group tends to be more vocal.

    • Hannah

      Pro meat lobby. They have deep pockets.