They do research on alcohol. I am sure that you knew that.
A recent study compared the effects of drinking whiskey to vodka. The two alcoholic beverages were similar except that those who over indulged in whiskey had worse "hang overs" than those who did the same with vodka. The symptoms being headache, nausea and thirst. The two groups did not have differences in performance or sleep.
In the news article from the BBC it was said that the reason may be that whiskey has more of something referred to as congeners than vodka does. In the article, congeners were said to be molecules and examples of them were acetone, acetaldehyde and tannins. Most of us have heard of tannins, at least I had heard of them, in regards to something in red wine that could trigger a migraine.
More interestingly, I had heard of the first two congeners with regard to tobacco. I thought, HUH, I bet that has something to do with the making of the product because a lot of times the toxins in tobacco are actually CREATED in the curing or fermenting process. And that was IT! I looked it up and in alcoholic beverages, congeners refer to chemicals that are created during fermentation. The term congener has several meanings.
So whiskey has more of these congeners than vodka. Alcohol scientists think that the congener content may lead to worse hang over symptoms. Brown University used over 90 volunteers to study the difference between the two alcohols. The research volunteers drank until their BAC was a third over the US/UK legal limit, so I think that would be about .1%. [btw, the chemicals are said to offer up aroma, flavor and color]
Long term over indulgence of alcohol has serious health effects which I would imagine could be attributed to some of the toxins that are found in alcohol. I may study this in the future, but at this time I do not know which types of alcohol, i.e. liquor, wine or beer - would be the worst. I do know that evidence exists to support some alcohol intake as health promoting if it can be done in moderation.
This research study was done in the USA, but the article I read was from the BBC and in that article there was mention of a charity that strives to promote responsible drinking. I went to their website and thought it was pretty darn cool. You might enjoy it as well. In the meantime, please do be mindful of all your food and beverage intake. Your body needs you to make wise decisions!