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    Food Allergy: Red onions = Headache
    nra0707 posted:
    I have been trying to research this for years now. Saw a few web posts of others who suffer from this over the years, but can't find a definitive answer. I seem to have a reaction to Red Onions, and specifically red ones...not yellow or white. Every time I eat it, I have severe headaches that cause my sinuses to clog, pressure behind the eyes, and a headache that can range from mild to crippling. I discovered this about 8 years ago when I ate red onions on a burger. Always resulted in a headache. I avoid it now as much as possible, but I'd like to know if anyone else suffers this and what could be the contributing elements in red onions. The only time I have similar effects is with certain red wines...but only a few...could be common in that they both share red color.
    LennyAZ responded:
    Actually, I have the same exact symptoms you describe. I just noticed it recently. After eating raw red onions in a salad, I feel intense pressure behind my eyes and fairly moderate headaches. Kinda sucks too, because I actually like red onions. I'm afraid I'll have to avoid them now.
    saidin43 responded:
    I myself have an intolerance to red onion only. But only if it's raw; if it is cooked, I have no problems. I can eat white or yellow onions cooked or raw with no ill effect. i do seem to have some issues with garlic, but its not so severe, usually just gas; doesn't matter if it is cooked or raw.

    My symptoms for eating raw red onion are different however: about 20-30 min after ingestion, i get bad gas, and diarrhea. Once I have 2 or 3 bouts, I'm ok again. I don't seem to experience any o the the symptoms you've mentioned though. Doing some reasearch now, and I don't know if an Allicin intolerance could be attributable...
    nra0707 responded:
    I realized after ingesting some red onions (prepared/hidden in my lunch) that I had posted the original message over a year ago. I still have not found out what it is; however, it could be a combination of allium intolerance or even flavonoids in the onions (as is present in red wines as tannins).

    I have consciously avoided red onions over the last 8-9 years and successfully prevented the painful headaches, but several of my friends believe that I'm faking it and it's all in my head.

    I'm hoping that by reviving this thread, others can chime in with their similar/alternate experiences with red onions.
    kawaiiko responded:
    It is an allergy. There was an article in CNN a few weeks ago about something similar. Here is the link to the article:

    I have been suffering from all these allergies to raw foods for years. I hear Benadryl works wonders for this.
    missjamie166 responded:
    Hello, I was looking this up since I realized every time I eat onions, red or white, cooked or uncooked, I get a moderate headache which lasts for about an hour. It is really weird! I am prone to migraines, but this isn't a migraine, just intense pressure behind my temples, my forehead and the back of my head, like my brain is swollen! So weird! I can't find any other info on it, and I was starting to think I was the only one!
    kelbeljrz responded:
    I have the same exact reaction. White onions do not bother me or even cooked Red Onions. Every time I eat red onions I get severe headaches. Mainly around my temple area and my eyes begin to hurt. I love seafood and just began to get headaches when I eat fish. I don't know if this has any relation, however the red onions are are the main problem. Hope we can find a way to fix this!
    TrudyGERD responded:
    I believe that red onions are one of the more common migraine triggers.
    kj_mpt responded:

    I too suffer from the raw red onion mystery and my friends and family give me "the look" when I try and explain.

    I can also eat them if they are cooked, but RAW - NO WAY!!!!
    I experience the similar symptoms as you have described and they also seem to trigger a migraine for me. The difference for me though is that the whenever I would eat raw red onions, the smell and taste seemed to stay with me for days. Once I recognized the trigger I stopped eating them and my family reluctantly, but graciously left them out of family gatherings.

    Due to the fear of the "raw red onion", I also do not eat any raw onions unless they are the sweet Vidalia Onions. I ran across an article only once describing the cause, but have never been successful in future attempts. I would really like to have something to stand on when I explain why I do not eat them.

    I do not seem to have any other food triggers/allergies, so this was a shock for me to see it as an "allergy". Makes complete and perfect sense. So I guess we just follow along with the old saying, "if you hurt when you do it, then don't do it"
    IAChris responded:
    I get headaches after eating red onions too!!!
    kikikolb84 replied to IAChris's response:
    For the past year I have suffered from terrible headaches and intense sinus pressure and it occured after eating red onions! I though I was crazy. I get really dizzy and my pains grows quickly...However i get no reaction to other types of onions.

    I also get the same reaction when I eat something with the flavor similar to "winterfresh gum" - weird.
    heartluver replied to LennyAZ's response:
    I have those same sympttoms, especially when I eat it on salads and I was wondering why I kept feeling that way....interesting....Thanks!!!! Now I know to avoid them!
    lizinchesapeake replied to heartluver's response:
    I have different symptoms!! I break out in itchy red dots on my face a few hours after eating red onions...raw or cooked. Anyone have these symptoms?
    MSjacqui replied to nra0707's response:
    Up until today, I wasn't able to put my raw onion consumption together with these awful headaches I've been getting. I love raw vegetables, not so much for their taste as for the fact that my body feels much better after consuming them than I do processed foods. Though recently I've been getting terrible the point where to move my jaw hurts my head! The only thing that's changed about my diet is the addition of raw, red onions..whose taste I actually love.

    I googled "red onions cause migraines?" and happened to read all of these similar experiences. Unfortunately I happened to read them AFTER I already ate my lunch and felt a headache coming (which then prompted me to do the search). I'm not sure if taking a Benadryl will help, as I'm not sure if it's truly an allergy, but if my approaching headache is anything like it was yesterday, I'll try anything.
    GlennLanteigne replied to MSjacqui's response:
    I am 42 now, and I have had this problem since my late 20's. After eating a red onion slide on a hamburger, I got the worst headache ever. I am also get killer migraines, and now red onions have become one of the triggers. I don't know what is in the red onion, and it does not matter if they are cooked or raw. I can eat any other type of onion and I am fine. This has become a major problem when eating out. You would not believe all of the meals that contain red onions. I have to declare my red onion allergy right up front as to avoid any ingestion. When I do, the cure is 2-3 ALIEVE tablets and a cold icy drink to induce a brain freeze (slushies are the best!). This also works of any of my migraines as well, and it's a life saver. I used to get the worst migraines, I mean the kind where you have to lock yourself in a dark room, with a chuck bucket and hope you'd die rather that endure the pain for 8-10 hours. Hope this helps others with the Red "Devil" Onion allergy and those who get migraines from other triggers. And if anyone can tell me what is in the Red Onion that causes this (not that it matters) let me know, people ask me all the time and I have no answer other than "that red juice in there". GL

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