If you are allergic to nuts you may have been told to avoid chestnuts along with all the other nuts. You may never have even eaten them in your life. But do you need to continue avoiding them?
What are chestnuts?
The definition in dictionary.com explains: “any of the several deciduous trees constituting the genus Castanea, of the beech family, having toothed, oblong leaves and bearing edible nuts enclosed in a prickly bur, and including C. dentata (American chestnut), which has been virtually destroyed by the chestnut blight, C. sativa (European chestnut), C. mollissima (Chinese chestnut), and C. crenata (Japanese chestnut).” It also includes the fruit and wood of the tree and the horse chestnut or conker tree.
Chestnuts are part of the Fagaceae family of trees, along with beech and oak.
The Anaphyalaxis Campaign share information about allergy to sweet chestnuts here. They discuss how this allergy is likely linked to cross reactivity or oral allergy syndrome where someone reacts to some pollens and fruits and also to some nuts. It could also be lipid transfer proteins (LTPs) reactions. Check out this blog, Allergy, Oral Allergy Syndrome or Lipid Transfer Protein reaction?
Allergy to chestnuts is rare but it can cause serious reactions in rare cases.
Are all nuts from the same family?
I found a very easy to understand definition on Wikipedia “Nuts are a composite of the seed and the fruit, where the fruit does not open to release the seed. Most seeds come from fruits, and the seeds are free of the fruit, unlike nuts such as hazelnuts, hickories, chestnuts and acorns, which have a stony fruit wall and originate from a compound ovary.” It’s worth reading this definition in more detail. I hadn’t realised for instance that most nuts in the culinary sense, such as peanuts, brazil nuts etc. aren’t nuts at all.
The complexities of nut allergies
You can have anaphylaxis to ground nuts and tree nuts and also have cross reactivity to other food groups like legumes and seeds. Some people can be allergic to just one nut type while others are allergic to them all. I am allergic to peanuts for instance, which itself isn’t actually a nut at all, it’s a legume which is in the same family as peas and lentils. However, I’m also allergic to most of the other nuts, including pine nuts, but interestingly not almonds. The protein make-up is very similar which is why the body treats them the same. But like all allergies, it’s complex and people can differ greatly in which nuts they are allergic to the severity of their reactions.
Watch out for chestnuts at Christmas time
If you are all allergic to chestnuts the Christmas festivities should have you on high alert. You can find chestnut in turkey stuffing, Brussels sprouts are also often served with flaked chestnut or almonds to added flavour. They are also used in many baked goods and more so in foods made for the Christmas market. They may also be roasted by street sellers during the winter so if you have an airborne nut allergy steer well clear of these.
Cross reactions with chestnut and latex
Chestnut allergy is also linked to latex allergy and I’m also allergic to latex so that’s probably the likely link here. If you have a latex allergy this could explain why you also react to chestnuts and vice versa. If you are allergic to latex, check out Latex allergy #101.
Keep children away from conkers and horse chestnuts
The Anaphylaxis Campaign also advise caution even where conkers or horse chestnuts are concerned for someone with peanut allergy. I’ve never had a reaction to conkers despite many playground battles. The difficulty is that no two people are the same – we all have slightly different reactions to different foods. All very confusing.
Should a person with a peanut allergy exercise caution, even though chestnuts aren’t directly related to other nuts? For now caution is the buzz word and with good reason. I made plans to ask my allergy dietician and request tests for chestnut as well as lupin just to be on the safe side.
My allergy to chestnuts and how it started
I have always been allergic to peanuts, cashews, hazelnuts and other nuts but I’d never knowingly eaten chestnuts, so how do you know if you might react?
What I did was get some allergy tests done at my allergy hospital, which came back negative. This isn’t necessarily a green light to say you’re never going to be allergic though, as I found out to my cost, and it’s interesting to observe how it became an allergy.
I don’t seem to come across chestnuts in ingredients lists that much in my everyday life, but once I thought they would be OK I did some careful testing. A local cafe used to make lots of lovely freefrom cakes using chestnut flour. I asked to try a tiny bit and nothing happened. I first put a bit on my lip and waited. Then took a tiny bite, and still nothing. My nut allergies are immediate, fast moving and devastating so this clearly seemed to indicate I wasn’t allergic to chestnuts. Don’t do this at home unless you are sure of what you’re doing and have sought your doctors advice. This was the advice they gave me, do it at home and slowly. I’m not sure this always wise but it’s the usual advice if tests come back negative. You can, and should however, request observed introductions at hospital. That seems far safe to me and I know many, especially children are offered this when reintroducing allergens people have grown out of.
The fateful cookery course and the chestnut flour
The same cafe ran a cookery class to learn how to make the amazing cake you see above, so I booked onto that and learnt so much. Looking at that photo I can still taste the cake, it was so good. Well anyway, to cut a long story short, I took the cake home and we slowly polished it off with no allergic reactions.
However… and ironically, it was on the day I ate the last slice it all went wrong.
I managed to eat almost the whole cake with no reaction
I took it out on a walk and when we stopped for a drink in a pub garden, I ate the last slice of this amazing cake. I felt OK, just a bit snotty, my nose began to run. I thought nothing of this at first but then we started walking, up a very steep hill. I wasn’t worried at first, but as walked further I began to feel very off. I had hives all over my scalp but not the rest of my face. I also had hives and swelling, strangely and at the time embarrassingly as I didn’t know what was going on at first, under my arms in my armpits and all in my genital region.
Very weird hives in very weird places
I had thought maybe I needed the toilet but when I crept into the bushes and pulled down my trousers it was clear something was amiss down there!
It was then that I thought this was an allergic reaction. My breathing was fine though and I didn’t feel like I was having an anaphylactic reaction, but I was disorientated and confused. We had my adrenaline with us but on that occasion I just took some antihistamines and sat down for some time. The swelling eventually went down and we continued on our walk but I was walking really slowly and very concerned that it might all start up again, as it often can do.
Now I am allergic to chestnuts
Suffice to say I am now allergic to chestnuts but it took a whole ass massive cake to get me sensitised and allergic. I also cut this cake up and froze quite a bit of it so it was also happening over a prolonged time.
I now avoid all chestnut related products and now realise the sense in the advice to avoid all nuts, even if you’re not allergic to all of them.
Strange aside, I can eat almonds… and continue to include almonds, in small and regular quantities in my diet. I buy almond milk every now and then and eat free from foods with almonds in them, my favourite being the Free From chocolate brownies you can get in Waitrose which are AMAZING.
And finally, water chestnuts…
Thank goodness, the Chinese water chestnut (Eleocharis dulcis) is most definitely NOT a nut, it’s a grass-like sedge grown for its edible corms. It grows in marshes, underwater in the mud, so stir fries are safe – water chestnuts are our friends.
You may enjoy reading: Should a nut allergic person avoid water chestnuts?
So yes, you probably should avoid chestnuts if your nut allergic
So, the answer to the question is probably, yes, you should exercise caution where chestnuts are concerned. No restnuts choasting on my open fire – not since reacting to a cake made with chestnut flour. I don’t even know what chestnuts taste like on their own. What do they taste like? Are they nice? Are they nutty? Anyone out there with a chestnut allergy?
Further reading
- Almond allergy #101 – how I can now eat almonds after avoiding them all my life!
- Am I allergic to almonds? – Sarah’s story about discovering the cause of her phantom anaphylaxis!
- Skin Prick Tests for allergies
The whole seed/nut business is really a nightmare, isn’t it…… I know that we tried to sort it a while ago on the FM site (http://www.foodsmatter.com/allergy_intolerance/peanut_treenut/articles/nuts_and_seeds.html) and honestly I think we ended up more confused than when we started….
As you say, it is, like all allergies, a very individual matter and to be really sure you need to be challenge tested for each nut to be really sure. See http://www.foodsmatter.com/allergy_intolerance/peanut_treenut/research/identifying_allergy_type.html and http://www.foodsmatter.com/allergy_intolerance/management_treatment/research/optimal_work_up10_11.html
Thanks for the links Michelle – really useful, but like you say, the more the delve the more you get confused. Then you get cross reactivity as Alex mentions below where latex allergy sufferers can be allergy to foods such as kiwi, chestnuts, bananas… sounds too weird to be true.
Ah, they’re delicious…. sorry. I wouldn’t describe them as nutty, actually. Quite a unique, distinctive flavour that it’s difficult to compare it with something else. I think most people with nut / peanut allergies are okay with chestnut. If I remember rightly, the people more likely to have a problem with it is people with latex allergies due again to cross-reactivity.
Happy new year, Ruth!
Hi Alex, Happy New Year to you too! Yes I agree, it’s probably OK, and since writing my next door neighbour has informed me that a pie she cooked for us once had chestnut in it and I was fine! So I have eaten them! Despite my latex allergy I survived the chestnut challenge without even knowing it! The Anaphylaxis Campaign has to take a vey cautious line I suppose. You can never tell how weird our bodies can be in reacting to odd stuff.
Hi Ruth, A very interesting quandry. I have often wondered about chestnuts and believed them to be a fruit but have avoided them so far. Now the conker reference is definitely of interest because when my daughter was very young (nrly 10 with various allergies including peanuts & kiwi) she loved to collect conkers but once in our local park she suddenly came out in a rash on her face having just been collecting conkers. I mentioned it at our following visit to the allergy clinic but they dismissed the possibility of a cross-reaction. However, since that day we’ve always made sure she washes her hands after collecting conkers. Also, I believe pine nuts are a seed.
We have a check-up on Friday so will raise the chestnut question with the doctor (even though it is now June and I don’t think we’ll be wanting to to eat roast chestnuts in Madrid with 30ºC+ temperatures!).
My son is allergic to eggs, peanuts and a variety of tree nuts, but not brazils. He has never been tested for cashew or pistachio. My reason for being here is the question of pine nuts – he has always avoided them but I don’t know whether or not he actually needs to!
I do have a slight problem with pine nuts but everyone is different. It’s so hard to tell. The only way to really know is to try them (very riskyk) or get tested. One friend said she rubs a bit into the back of her childs neck to see if he might react. You could try that. I have a peanut allergy but am fine with almonds, but not so sure about pine nuts. It’s all so complex… Really you need to seek medical advice on this one. The other added problem is that nuts can be contaminated by other nuts – so just because almonds are OK for, doesn’t mean they are always safe because they are often stored i the same polace as peanuts. VERY hard to know.
Every time I eat chestnuts I get really ill with symptoms such as severe vomiting and diarrhea. It happened a few times when I was a kid and I didn’t link it to the the chestnuts I collected and scoffed. Recently (in the last 2 years) I have eaten chestnuts twice and the same thing has happened. I didn’t believe it at first, but that second time i didn’t even eat the chestnuts, just ate the spinach around them and WHAM. Now i have never visited a doctor about this but i am seriously considering it now especially since i have just read that it could get worse without me knowing about it. i do not have any other nut allergy.
Chestnut allergy is very rare so you are very special. I would visit your doctor and look out for baked goods and pastry, especially at this time of year. Even sprouts can be done with chestnuts. You’re right too about reactions getting worse – the body learns well that for some unknown reason it doesn’t like chestnuts in your case. Stay safe!
I have tried different nuts and products that aren’t considered ‘nuts’ like coconuts and pistachios, which are considered one seeded drupes according to the info I’ve found. I’m just as allergic to them as I am to pecans, walnuts, hazel nuts, almonds, cashews and those pesky peanuts (I know, I know a peanut isn’t a true nut but I’ve developed an allergy to them in adulthood). I’ve even tried oils made from exotic ‘nuts’ like Argon oil. Did a skin test on the inside of my arm near the elbow and almost immediately developed a welt in that area. I washed it off quickly but still developed itching all over my body. My ears became hot and bright red and my tongue began to swell a little. All of this while benedryl was coursing through my body. Jumped into luke warm shower to wash my whole body and that helped. Strange thing is I tried shea butter which is derived from the shea nut and I had no problems. Go figure.
Hi, i have a severe allergy to peanuts and hazilnuts and suffer anaphylaxis to pine nuts but am fine with walnuts and almonds (not 100% sure about any other nuts and too scared to try). I am spending Christmas in the UK this year and it seems i can’t escape chestnuts. The smell of them roasting doesn’t make my throat and eyes itchy like
peanuts and im dying to try them…are they more similar/closer related to walnuts or hazilnuts or another nut, or none?
I think I can eat chestnuts (have had them in a pie by mistake and had no reaction), although I too have a peanut allergy. I don’t seem to be allergic to almonds either – it’s all very complex and no two people are exactly the same. You do need to be really careful. It could be VERY risky. I couldn’t possibly advise you to just try some, but I wonder if you could see whether they might irritate your skin? or rub a tiny bit on your lip? Just be VERY, VERY carefull… not worth ruining your Christmas over. I do agree though – they smell amazing, whilst peanuts smell like pure evil poison and make my throat shudder just from a whiff. Urgh!
What about horse chestnuts?
I want to buy this hydrafirm eye and lip gel with horse chestnut extract in it, but the word “chestnut” worries me.
Please help!
Horse chestnut is a plant, not a nut.
Hi Lorelei, yes horse chestnut is more of a vegetable but chestnuts are tree nuts. I appear not to be allergic to chestnuts though, and ate some horse chestnuts in last night’s stir fry! Yummy
Scratch that, I did just have an allergic to something and suspect chestnut flour mixed with a pint of ale and a strenuous walk. Not a good mix it would appear.
im not allergic to cashewes i dont think but peanuts i am so i make buckeyecandy with cashew butter instead of peanut butter so good
Thank you so much for your website and also to the commenters. I’m allergic to walnuts, pecans, hazelnuts, pine nuts, etc, but not peanuts or almonds. I used to be able to eat pistachios, but in recent years I have a mild reaction to those too. I’ve eaten water chestnuts many times with no reaction, but a recipe I’m considering called for roasted chestnuts. I just learned that water chestnuts and roasted chestnuts are two different things (the first is a swamp plant and the other is a tree nut). So based on the information on this page, I think I might give them a try. Fortunately the worst for me is feeling more awful than I can describe for anywhere from a few hours to two days, but no anaphylaxis or hospitalization (thank goodness). I just carry diphenhydramine with me in case I ingest something by accident. Makes me so sleepy, but it’s worth it to stop the reaction. Again, thank you all for your page and comments… so helpful!!!
I’m wondering if it will be safe for me to try a cream to get rid of spider veins or varicose veins they all seem to have horse chestnut in and as it soaks into your skin I’m nervous about trying it. I have a peanut allergy.
I’m also allergic to Ibuprofen and last year when I accidentally used a muscle rub cream that I didn’t realise you weren’t meant to use if you had an allergy to Ibuprofen (though it didn’t state any on the ingredients list) my leg swelled up to double the size and left permanent damage to my veins in that leg! So understandably I’m nervous about risking the ‘Vein away’ cream.
I’ve looked for others but they all seem to contain ‘Horse Chestnut’
I seem to be allergic to chestnuts. I ate some in stuffing at Christmas and lips swelled up . I took deltacortril and antihistamine and it resolved after 12 hours or so. I just went under horse chestnut tree today and rubbed against some sap on lawnmower and got contact dermatitis on my hand which subsided after 3 hours and also had tingling tongue for a few hours. Now resolved thank goodness!
Gosh, stay away from those chestnuts! Glad you feeling better now.
I have just looked at the pigs in blankets I purchased for Christmas and notice the bacon is smoked in chestnuts. Think I will give away to neighbours.
Oh Damn! Thanks so much for this heads up. We usually make our own which is a faff, but probably safer if this could happen.