# Digestion of cooked vs Raw onions (TMI warning) **URL:** \ **Category:** Factual Questions\ **Created:** [August 1, 2007, 3:41am UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919 "2007-08-01T03:41:04Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![pkbites](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/pkbites/32/204_2.png) [@pkbites](https://boards.straightdope.com/u/pkbites)\ **Post date:** [August 1, 2007, 3:41am UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919/1 "2007-08-01T03:41:04Z")
Most of my adult life I’ve noticed that onions have a different effect on me base on not what type they are, but whether I’ve eaten them cooked or raw. Raw onions in a salad or piled high on a hamburger have no effect on me regardless of the amount eaten. Cooked onions are a horrifyingly different story. Fried or baked onions produce a toxic gas that could force a freight train to take a dirt road to avoid me. My wife says shes making a homemade french onion soup for dinner tomorrow. That means I may end up sleeping in the garage out of loving consideration for her. Why this effect from cooked onions but not raw? ---
**Author:** ![Duck\_Duck\_Goose](https://avatars.discourse-cdn.com/v4/letter/d/50afbb/32.png) [@Duck\_Duck\_Goose](https://boards.straightdope.com/u/Duck_Duck_Goose)\ **Post date:** [August 1, 2007, 4:36am UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919/2 "2007-08-01T04:36:31Z")
Since the heat of cooking drives off most of the volatile sulfur compounds that are the onion’s active irritant, my WAG would be that you personally don’t happen to chew up the raw onions you may encounter in a sandwich or salad well enough to release those sulfur compounds into your intestinal tract, so the chunks of basically unchanged onion merely shoot right through and out the other end, whereas cooked onions, being softer, get masticated somewhat better by you, and are able to release what remains of their sulfur, to deadly effect. Try wolfing down the French onion soup. You have to eat it, you know, or else she’ll cry. 😃 ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [August 1, 2007, 7:48am UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919/3 "2007-08-01T07:48:45Z")
Interesting - I have somewhat the opposite predicament - cooked onions I can eat by the plateful - raw onions, though I love them, give me symptoms resembling a hangover within minutes of eating. ---
**Author:** ![CookingWithGas](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cookingwithgas/32/485_2.png) [@CookingWithGas](https://boards.straightdope.com/u/CookingWithGas)\ **Post date:** [August 1, 2007, 2:20pm UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919/4 "2007-08-01T14:20:51Z")
I have a friend who also has the opposite problem. He says that raw onions have something that he does not have the enzymes to digest, and his gut bacteria are only too happy to do the job, releasing copious amounts of gas accompanied by much discomfort. This is similar to lactose intolerance. If onions are sufficiently cooked, he doesn’t have as much of a problem but he avoids them anyway so as not to take chances. ---
**Author:** ![CalMeacham](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/calmeacham/32/35_2.png) [@CalMeacham](https://boards.straightdope.com/u/CalMeacham)\ **Post date:** [August 1, 2007, 2:28pm UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919/5 "2007-08-01T14:28:49Z")
> [@](#): > > Interesting - I have somewhat the opposite predicament - cooked onions I can eat by the plateful - raw onions, though I love them, give me symptoms resembling a hangover within minutes of eating. Maybe you’re a vampire. Better stay away from the garlic. ---
**Author:** ![BwanaBob](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bwanabob/32/2985_2.png) [@BwanaBob](https://boards.straightdope.com/u/BwanaBob)\ **Post date:** [August 1, 2007, 2:35pm UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919/6 "2007-08-01T14:35:40Z")
Are talking about the “larger” onions, such as Bermuda? I have no problems with these, raw or cooked; but heaven help the world when I eat those little pearl onions. They must have something special inside them to cause such gaseous havoc. ---
**Author:** ![lieu](https://avatars.discourse-cdn.com/v4/letter/l/c2a13f/32.png) [@lieu](https://boards.straightdope.com/u/lieu)\ **Post date:** [August 1, 2007, 2:41pm UTC](https://boards.straightdope.com/t/digestion-of-cooked-vs-raw-onions-tmi-warning/413919/7 "2007-08-01T14:41:16Z")
[QUOTE=CookingWithGas] … onions … [/QUOTE] OP, meet perfect username.