Irn-Bru makes me sleepy. Any idea why?

July 23, 2007 2:07 PM

Irn-Bru makes me sleepy. Any idea why?

I'm Scottish and like many other Scots, I was raised on Irn-Bru. If you're not familiar with it, it's a bright orange carbonated drink produced in Scotland since 1901. It outsells every other carbonated drink in many areas of Scotland and is the third most popular soft-drink in the UK.

The problem is... I've started to notice over the last 2 or so years that about 20 minutes after drinking it I get very drowsy, often to the point of falling asleep. I wake up later feeling drained and exhausted.

This never used to happen, and doesn't happen with any other soft-drink. I prefer Diet Irn-Bru (the sugar free variety) but this seems to happen with both diet and regular. I've asked many friends but can't find anyone else affected in this way.

Actually, nothing I drink or eat does this to me at all. Only Irn-Bru. And the effect is so strong, I usually just slump over on my bed and snooze for a while. It's not a normal sleep. It's a drowsy, drained and sluggish sleep. It's kinda horrible actually and leaves me feeling pretty crap.

I don't drink it as much as I used to because of this, but I really like it. I'd like to be able to drink it more often. The question isn't "how do I stop the happening?" (the obvious answer to that is to stop drinking it). I just want to know why it happens in the first place.

Does anyone have any insight into why this might be happening? Bonus points of a definitive answer!

Thanks MeFites! :)

posted by TheAspiringCatapult to Food & Drink (7 answers total)

Late-onset girder allergy?
posted by zemblamatic at 2:29 PM on July 23, 2007

Have you tried drinking it when you don't have a hangover?
posted by TheManticore at 3:51 PM on July 23, 2007

I don't know if that's a possible allergic reaction, I'd guess that it is. Several people in my family can't drink Irn Bru at all because it gives them rashes or asthma attacks, it's the food dye, and I understand it's a common ingredient to react to.
posted by crabintheocean at 4:19 PM on July 23, 2007

This coloring, which is (sort of) banned in the US.
posted by crabintheocean at 4:32 PM on July 23, 2007

It could also be a sugar crash. Irn Bru has something like 22 spoonfuls of sugar in a given amount (I can't remember if it's a can or bottle)
posted by bonaldi at 4:37 PM on July 23, 2007

Unless you are diabetic or hypoglycemic, sugar rush/crash is a myth.
posted by BrotherCaine at 7:24 PM on July 23, 2007

Thanks. From what I've read, Sunset Yellow FCF might just be the culprit! I doubt it's sugar rush/crash - it happens with diet (sugar free) Irn-Bru too and I'm not diabetic or hypoglycaemic.

Again MeFi prevails! Thanks!
posted by TheAspiringCatapult at 2:47 AM on July 24, 2007