With a powerfully pungent smell and super stringy, sticky texture, natto (fermented soybeans) is one of Japan’s more divisive foods. Traditionally natto has been less popular in west Japan than in the east, but there’s another demographic that has less gusto for gobbling the gooey soybeans, and oddly enough it’s surfers.
This curious phenomenon comes up periodically, and it’s back in the spotlight recently after a Twitter user posted about how roughly 80 percent of their surfer friends don’t like eating natto, because they have allergic reactions to it.
That’s a much larger proportion than among the general public, as natto allergies aren’t particularly common in Japan. As the tweet briefly points out, there’s actually an indirect connection between surfing and natto allergies, and the junction comes in the form of one of the unpleasant inevitabilities of spending a lot of time in the sea in Japan: jellyfish.
Okinawa excepted, outside of summer the weather in Japan isn’t warm enough to be very conducive to marine sports, and June is characterized by frequent rain and thunderstorms. That makes July and August the prime surfing months. Once August comes around, though, you can expect to encounter jellyfish at just about any beach in Japan for the rest of the summer, but if you’re a surfer, that’s also likely to be when you’re trying to get in as many sessions as possible, and there’s a very good chance that on one of those sessions, you’re going to get stung.
While painful, most Japanese jellyfish stings aren’t particularly dangerous, so many surfers see them as an acceptable risk, and an unavoidable byproduct of the hobby. Jellyfish tentacles produce a substance called polyglutamic acid, or PGA, which the human victim is exposed to when stung. Human skin isn’t fond of getting hit with that much PGA at once, which results in itchy, painful welts.
PGA is also produced, though, as part of the soybean fermentation process in making natto. Ordinarily the amount is small enough that it doesn’t present a problem for the person eating it, but jellyfish stings can cause increased sensitization to PGA. Get enough jellyfish stings, and your body eventually starts saying that enough is enough with the PGA, and even the quantity present in a serving of natto can become enough to trigger an allergic reaction.
Now depending on your personal feelings about natto, developing an allergy to it may not be a concern, and could even be to your advantage if you’re looking for an excuse to politely but firmly decline it when it’s offered by your Japanese homestay family, friends, or coworkers. But if natto is something near and dear to your culinary heart, you’ll probably want to keep your distance from jellyfish.
Sources: Japan BD, International Journal of Emergency Medicine, Hachima Kiko
Read more stories from SoraNews24.
-- Natto allergy is caused by jellyfish stings, says surprising Japanese study
-- We spice up our fermented soybeans with curry powder flavored natto【Taste Test】
-- Natto for beginners? How to half-make Japanese fermented soybeans at home【SoraKitchen】
© SoraNews24
15 Comments
Login to comment
BertieWooster
Well, as I've never surfed in my life and, at my age, have no inclination to start, I'm relieved to find that I can continue to enjoy natto with no unwanted side effects.
Mike_Oxlong
Toxins always win in the end. Ingest them over the long term, expect to pay a price.
piskian
Total nonsense.
I have surfed since I was a toddler,been stung countless times by jellyfish,love natto more and more as I get older.
None of my ocean-loving friends hate natto,only the Kansai ones don't particularly enjoy it.
Hate this unsubstantiated stuff.
Unworthy of a relatively reputed news site.
virusrex
Things that run contrary to a personal experience may seem counterintuitive or false, but when they are supported by objective evidence it is invalid to call them nonsense, it is simply that not everybody gets allergy, but of those that do marine sports is a frequent risk factor.
It is not unsubstantiated.
https://www.jstage.jst.go.jp/article/allergolint/67/3/67_341/_article/-char/ja/
Hervé L'Eisa
Of the 140 outpatient participants in the study (rather small study sample), 13 of the 140 were allergen sensitive. The study didn't account for other possible causes of heightened sensitivity of their histamine systems.
People have allergic reactions when their histamine system exceeds the threshold for the individual. Having a raised histamine level can be caused by a number of variables.
Surfers (myself included) are exposed to increased amounts of chemicals and bacterias, especially if they surf in or near rivermouth areas. Surfers also more frequently use sunscreen lotions that may trigger allergic reactions to the chemical ingredients.
The conclusion of the survey is possibly oversimplified.
Megan Thee Stallion
Stinky but pretty healthy I hear.
BeerDeliveryGuy
I know about 20 surfers, and not one of them even heard of this phenomena.
virusrex
Which makes absolutely no importance about their conclusion. Surfing is an independent risk for this specific cause, and the PGA provides a rational reason for this that was confirmed by tests, having a plausible explanation that has evidence behind it there is no reason to search for another explanation, that is reserved for when you already have a better one that fit better the evidence.
Completely false, histamine is the product of an allergic reaction, not the cause of that reaction. It mediates the symptoms but it is not the original process that begins the allergic cascade. In this case PGA was proved in the report without problems.
https://www.medicinenet.com/allergic_cascade/article.htm
Yet the PGA was specifically correlated with the reaction, which would not be possible if the cases were due to inespecific "chemicals and bacteria". Other people use sunscreen frequently without them being described as specially vulnerable.
Based on a false understanding of what allergies are, lack of evidence that should be present in your scenario and presence of specific evidence that proves the rationale? no. It still fits much better the observed phenomenon than your contradicting explanation.
Yet this is well described https://shirasaki-hifuka.com/blog/?p=1387
Since natto allergy is not frequent it can be 20 times higher in surfers and it would still be difficult to find cases, so knowing many surfers without this allergy do not disprove the article, for that it would be much more important to know many cases of natto allergy without anyone being a surfer. Is like the well known relationship between latex and allergy to fruits like mango. You may know lots of people that use latex (doctors, nurses, etc. that use gloves all day long) without anybody being allergic to mangoes, but if you know many people will allergy to the fruit it would be much more likely that some of them are people that use latex frequently.
gaijintraveller
Do jellyfish stings penetrate wetsuits? There are many surfers in my area. The Olympic surfing was held nearby. All the surfers seem to wear wetsuits. A surfer without a wetsuit is a rare sight.
zibala
a Twitter user posted about how roughly 80 percent of their surfer friends don’t like eating natto, because they have allergic reactions to it.
Interesting that because a Twitter user posts something, people here believe it.
Totally false and without any substantiation.
virusrex
There are already references from doctors and scientists that prove the same thing.
Seeing how you were unable to bring even one argument to defend this point it is clear you are the one making baseless and false accusations.
zibala
Oh, so Twitter quotes+ a few doctors and scientists equals the truth!!
You brought an argument based on appeal to authority so no reason to argue against that--your argument already failed.
virusrex
Of course, when confronted with zero contrary evidence that is a perfectly valid argument.
Appeals to a valid authority ARE also valid arguments, specially when they come with scientific evidence like the report also included, baselessly claiming they are wrong without any evidence would be the fallacy.
So any evidence the actual experts in the field are wrong? other than your supposed anonymous authority?
zibala
Of course, when one circularly relies on their own opinion and professes it to be fact there is another elementary fallacious argument.
Appeals to authority like yours explained below:
Appeal To Authority - Definition & Examples - Logical Fallacies
https://www.logicalfallacies.org/appeal-to-authority.html
virusrex
Still completely false, there is evidence and a valid authority supporting the claim, not anyones personal opinion. Your argument is still without any merity.
Perfectly valid appeals to authority.
https://en.wikipedia.org/wiki/Argument_from_authority
(with four references for this)
Pretending you have authority to refute both the professional opinion of experts and the evidence of the scientific report linked