Why am I allergic to soy milk but not soy sauce and not all tofu?

16 comments

1. Do you have birch pollen allergy as well?

   Soy sauce and natto are fermented so many of the allergens are broken down.

2. [deleted]

3. I was once told by a doctor that the liquid is processed faster by the body (you don’t consume that much soy sauce for a proper reaction) so an allergic reaction may appear, when it won’t in other cases.
   Also cross allergys may play into it as well as the production process of the food you consume.

4. No issue with soy sauce, soybean, or savoury tofu dishes.

   I start having allergic reactions to soy drinks, soy milk, and dessert tofu.

5. I’d guess it’s due to fermentation breaking down the allergen in the case of the soy sauce and natto.

   For the tofu, it’d be useful to know which kinds you can tolerate and which you can’t, but without that info
   I think it’s due to the fact that not all tofu is manufactured using the same coagulant, there are actually four commonly in use according to this article: https://misosoup.site/different-types-of-coagulant-for-tofu/

   My guess would be that the various coagulants actually pull different constituents from the soy milk when the tofu is made, and the ones you can tolerate don’t coagulate the compound you are reacting to.

6. Soy sauce and Natto is fermented products… Maybe that is producing different results?

7. My wife and MIL have the same issue, you’re not a freak OP. My MIL can eat Tofu, Natto and Soy Sauce no problem, but recently went into anaphylactic shock because she ate Ramen that had a tiny amount of Soy Milk in the broth. My wife is like you and only gets a mild reaction (throat starts to itch and swell a bit), but the docs said it can get more dangerous with age like in the case of MIL.

   I think I remember the doctors said soy milk simply has a much higher and pure concentration of the allergen than other soy products, which is why the reaction was so severe. Wife and MIL also share allergies to apples, peaches and cherries which according to the docs may be related to the soy allergy, so maybe be careful around those too.

8. I’ve noticed this recently as well. After having a soy milk based chowder. I then tried soy milk straight a few days later and got the itchy throat again. No issues with tofu or other soy products.

9. Typical soy milk allergy. People who exhibited no allergic reactions to soy products suddenly find themselves having reactions after drinking the “healthy” soy milk.

   This allergy is caused by Gly m 4. People who are allergic to birch and/or Japanese alder are at risk because they have a similar protein, although many may not realize they have one because their season coincides with many of the more famous pollen allergies.

   The protein breaks down during heating or fermentation processes, so people will be fine eating miso, soy sauce, and firm tofu, but will have an allergic reaction to edamame, yuba (curd skin), soft tofu, and soy sprouts (大豆もやし), which are unfermented foods that are cooked only for a short time.

10. Thank you for the responses everyone.

    Good to see this is a thing and not as weird as I thought.

    Looks to be down to some very specific scientific details however as a basic overview the types of protein and fermentation seem relevant.

    Thank you

11. Because you are an alpha not a spy boy /s
    Joking aside, soy sauce is fermented so some of the allergens are gone

12. I never had any experience that would suggest I was the slightest bit allergic to soy. Natto, miso, soy sauce, and drinking Trader Joe’s soy milk constantly.

    One day I decided to upgrade to the TJ organic soy milk, opened a fresh pack and tried it in the morning. Few minutes later I had a itchy throat that would then turn into difficulty breathing.

    I don’t remember passing out, but when I came to it was late at night.

    Ironically I am ok with organic versions of most fruits that I am allergic to. I really don’t know what I should avoid or not these days.

13. I’m allergic to any milk I think… If I drink a cop toilet needs to be there…

14. I have the same thing. Some fresh tofu make my mouth tingly. It sucks that I can’t eat soy based broth tantanmen, but at least I can still enjoy my TKG natto kimchi.

15. I have the same problem and it took me a while to realize that I am allergic to soy milk. No problem at all with tofu or soy protein powder.

    The allergy screening came out negative. When I asked the doctor about it, he said because it’s a byproduct it could have different component then the original thing.
    Which makes kind of sense, if it’s processed there could be chemical change.

16. you’re not the only one, although i only get the throat itches to soy milk occasionally now. it’s only ever soy milk. i eat edamame and there’s no issue. weird, i have a stronger allergy to tree nuts, especially of the prunus and pyrus genus, all of them (especially almonds and apples) but weirdly, never any issues with cherries. it’s potentially an issue with cyanogenic glycosides, which is probably why my throat and tongue tingles also with bamboo shoots sometimes.

    i’ve kept off them for a while now but i remember a time when i had almonds in a soup and a few hours later scratched up my throat until it was bleeding profusely and i didn’t even notice until i felt my hands were damp from the blood, because it was more soothing to keep scratching… 🙈