I am a runner. I am also the brother of "Karl S" who is a pretty active Chowhound member; he pointed me to these forums (Thanks!)
Over the last several years, I have paid close attention to something that happens occasionally to me, and I am wondering if there are other people who get the same thing, but haven't been able to isolate it.
Here's the deal:
For many years, there were times I would go out for a training run (typically 10K, but could be 5K, 10 miles, whatever), and during the run, I would develop a tingly, itchy, red, hot rash over most of my body (most noticeably in my trunk). The rash would usually go away within a couple of hours of finishing my run.
It took me a really long time to figure out what was causing the rash. At first I thought it was just heat or dehydration, but that proved not to be the case. (Medical review revealed that it's not an allergy as well).
Then I thought it might have to do with my vitamin supplements, since the reaction was very similar to a "niacin flush" that I had experienced when taking Niacin several years ago (something I never did again!). So I stopped taking them for a while.
Of course, I considered what I had eaten, and noticed that it would almost always occur after having a meal of Mexican food.
But not always!
Several more months go by, and...
Lo and behold, I discovered that it was *tortilla chips* that caused the rash! And the more I ate, the worse the rash was. But even if it was just 10 or so, I would get the rash. (I had to run within an hour or two of eating the chips; longer waits eliminate the issue consistently.)
So, I wondered something: is there some sort of extra amount of niacin in tortilla chips?
Product packaging didn't seem to note it. But then again, snack food manufacturers don't have to report all vitamins that occur in their foods, unless they happen to add the vitamins as supplements.
So I did some research about how corn is prepared for tortilla chips, and, well, wouldn't you know - when ground corn is processed in its usual manner (with lye, etc.), it releases a fair amount of niacin! This was discovered during the fight against Pellagra in the 1930s:
More information is here:
You can Google the rest.
So: Tortilla chips + running shortly thereafter = handy way to get a niacin flush? Indeed, at least for me.
Here's my point: I read things all the time (including in Runner's World) about people having mysterious rashes that sound suspiciously like what I am dubbing "Tortilla Chip Flush" - but I don't think there has been a study with a group of runners to get a sense for how common this condition might be.
Is anyone out there willing to risk a Tortilla Chip Flush in the interest of science?
(Also posted in http://www.runnersworld.com/community...)