29 ms·

What does one have to do with the other? We live in a time of significantly more advanced medicine and understanding of the human body. Just because we used to

• magicalist 4y ago
  It's absolutely not backwards. More children developed allergies (almost definitely because of the lack of exposure), but it wasn't known that would happen. What we did know is not exposing children to a trigger of anaphylaxis would prevent them from dying from anaphylaxis, so, similar to many dangers, the most logical course of action is to remove the risk altogether. Yes, it's well known doing that with anything can have unknown secondary effects, but there's also a million everyday things we logically don't let infants do or be exposed to that we aren't establishing the statistical significance of either. Incidentally, with all of our advanced medicine and understanding of the human body, we still don't understand why some people develop severe allergic reactions to some foods and others don't, so let's not pat ourselves too hard on the back for developing better food exposure protocols from trial and error over decades.
  • dap 4y ago
    > It's absolutely not backwards. But it is. The best population-level guidance (now) is early exposure. We told people to do the opposite. The result was a lot more kids with anaphylaxis-level allergy. (I don't know if this increased the total number of people who died. That'd be an interesting question, but given that we reversed the guidance, I assume from a public health perspective people now believe the original guidance was exactly the wrong thing to do.) The best you can say is this was the best we knew at the time, but it's exactly wrong. > What we did know is not exposing children to a trigger of anaphylaxis would prevent them from dying from anaphylaxis, so, similar to many dangers, the most logical course of action is to remove the risk altogether. I think you mean that it's intuitive, but I don't think it's logical, for exactly the reason that it turns out not to be a good idea. It's based on a wrong model of how the world works. Yes, that wasn't known. But I feel like we have to account for the fact that we might not know everything. (Admittedly, this drives me particularly nuts because I think this fallacy pervades so much public health advice, especially for kids.) Like I said above, I get that people need to make recommendations in the face of uncertainty. But I feel like when we find that we've recommended the exact opposite of what was good (i.e., exactly flipped the previous guidance) with such severe consequences, it seems appropriate to step back and look at our methodology to ask if something went wrong or if there's something we can do to improve it?
    • magicalist 4y ago
      > I think you mean that it's intuitive, but I don't think it's logical, for exactly the reason that it turns out not to be a good idea. If operating with the best model you have is intuitive and not logical, then everything in science it intuitive and not logical, so we might have to redefine your use of "logical" to be more useful. Peanut exposure caused anaphylaxis in some kids. Many kids in the world are never exposed to peanuts with no ill effects (in fact, a large portion of the globe went all of recorded history up until the Columbian exchange without exposure to peanuts). If we still want peanuts in anyone's diets, waiting until the child is older for controlled exposure is a logical response. Yes we didn't know how that would affect developing allergies, but as I mentioned in my comment, we still don't understand how allergies develop, so the only difference is we conducted a massive peanut exposure experiment with other countries operating as incidental controls. > I don't know if this increased the total number of people who died. That'd be an interesting question In fact, this (plus quality of life + cost of prevention/treatment) is the only measure on which the old guidance could be "exactly wrong", which hopefully gives some insight on why talking about it being "backwards" is itself wrong. It's not Thalidomide. Exposure at 6 months isn't the opposite of exposure at age 3. And whatever harm metric you can define is going to be a result of a mixture of effects, including allergic kids that weren't exposed and kids that (probably) developed an allergy because of the lack of exposure. It's almost certainly on the cost side that it's come out negative, because treatment has improved and exposure prevention has become so widespread. > It's based on a wrong model of how the world works. Yes, that wasn't known. But I feel like we have to account for the fact that we might not know everything. (Admittedly, this drives me particularly nuts because I think this fallacy pervades so much public health advice, especially for kids.) I mean, all models are wrong, some are useful. We'll never know everything and you have to work with the evidence you have. Delaying exposure to something that could kill 1% of kids is categorically different than some new study saying "we detected a small magnitude but statistically significant result on speech acquisition due to magnesium supplementation". If you instead mean we need to better communicate uncertainty in developmental and health recommendations, I completely agree. You can see it in this thread, for instance, assuming that early exposure prevents all peanut allergies. Even if you assume exposure is the only causal variable here (almost certainly wrong), we can observe a baseline level of peanut allergy incidence, so, no, early exposure is not a panacea, but that doesn't seem to have been communicated well.