Continuing with the xmas theme of over-drinking...
If i drink enough wine, I usally start to feel very sleepy, after more wine, I start to get a headache..Why is this? What might the component of the wine be that causes this??
They have found that red grapes contain high levels of Melatonin (specifically the skin of the grape), which could help regulate sleep patterns.
Red wine headaches (RWH) are not too uncommon. Some people are very sensitive to red wine and can be more prone to these headahces. I won't postulate on why because there is no definitive answer at this point.