You’ve been at that party where someone says, “Oh, no red wine for me. It makes me so sleepy.”
Is there any truth in there?
Yes. The phenolic elements of the grapes (seeds and skin) contain melatonin, a hormone produced by the brain, that controls your sleep cycles. Fermentation, supposedly, increases the amount of melatonin. So there is a scientific explanation to the sleepiness. Since red wines have more contact with the skin, the melatonin levels in red wine would ultimately be higher than in white wine, meaning red wine should make us sleepier than white wine.
But we have to consider scale. A glass of red wine might contain anywhere between 60 and 120 nanograms (nano meaning one billionth) of melatonin. The melatonin pills we take to sleep (we all take those, right?) contain about 10,000 times as much. Even if we drink more than we should, we likely don’t drink enough to incur the kind of sleepiness that a melatonin pill induces.
So what are the likely culprits? The fact that you’re out, drinking, and drinking wine. (Or any alcohol.) At the end of the day, the melatonin is a bit of a shove into sleepiness.
