Weekend wonderings: MSG and night wakings

Little boy has never been a good sleeper until some time ago, when we finally managed to get him to sleep on his own in his room (after a period of night-weaning).  For the past few months, there have been some peaceful nights where he would wake once a night, or sometimes none at all, interspersed with some nights where he would wake up a few (or many times!) screaming and crying.  So far, we attributed most of these night-wakings to him falling sick or teething.

However, we also noticed another trend: if we fed the boy outside food, there was an increased likelihood of him waking up at night.  Make it Asian food (especially Chinese restaurants), and the likelihood increases even further.  So we suspected that the consumption of MSG (Monosodium glutamate, or what is sometimes known as Ajinomoto) might be the cause of some of these night wakings.  Initially, I thought it was just paranoia on my part, but we started being very careful about the stuff we fed the boy when we ate out.  I would try to either bring out home-cooked food for the boy when we ate out, or would try to avoid food that had a higher likelihood of containing MSG.  The problem seemed to improve somewhat, and the frequency of nights having the boy wake up 6-8 times a night screaming his head off decreased.

The hubby and I in general seem to also react to MSG as well.  For the hubby, consuming MSG in food makes him thirsty, and sometimes results in him being unable to sleep (which seems to be a known effect of MSG).  I too, get extremely thirsty and start getting headaches after an MSG-laden meal.  So it probably comes as no surprise that the boy too may react to MSG.  Not only does it seem to affect his sleep, it also seems to make him hyper.  Just this weekend, we had sandwiches and soup at a eatery (we assumed MSG was not added to their food, as they sold all the healthy stuff!).  However, hubby and I ended up feeling really thirsty after the meal, and the little boy got extremely hyper (and was so revved up, he couldn't go down for his afternoon nap!).  That day, hubby had to babysit the boy as he bounced off the walls while I took a nap, and henceforth has concluded that yes... we'd better stay far away from MSG in the boy's case if possible!  (He used to say I was paranoid, heh.)

The odd thing is, it seems that most scientific research on the effects of MSG have been inconclusive (click here for a pretty comprehensive discussion on the topic), and most of the evidence has been anecdotal (for example, this parent's sharing on how MSG seemed to trigger off night terrors in her daughter's case).  We've had a close friend who has also observed the same trend, as her daughter would wake up over 6 times a night after eating out at eateries serving Asian food (to the point that she orders sandwiches now when she eats out), so we're not ditching our theory as of yet.  Of course, the grandparents all tell us the boy needs to get his chicken rice and other local yummies, to build up some tolerance to MSG, but then again, they don't have to stay up with the kid while he thrashes around in bed and cries through the entire night!

So I'm curious... do any of your kids experience night wakings, or get really hyper after eating a meal containing MSG?  Do share!