title_body: Alcohol to improve blood flow?
upvoted_answer: Alcohol relaxes your blood vessels as it is a vasodilator.
  
  That means it can improve blood flow - although the negatives far outweigh the positives and most people aren't required to take vasodilators and can be harmed by them. 
  
  This is also where the old wives tale about drinking whiskey if you're cold comes from (think St Bernards). It can save your fingers from frost bite, but your body is actually restricting the blood flow for good reason - you may loose fingers but you have a better chance of survival - so it's better to only have that whiskey once you're back in the warmth. Drinking will relax the capillaries in your fingers and toes, allowing the warm blood from your centre-of-mass to flow. This actually means the overall temp of your body will cool down.
  
  As to which kind is "best" it's simply the drink with the highest alcohol content.  Hence traditionally something such as Whiskey or Brandy. For added effect though, you could consider drinks with a high concentration of other naturally occurring vasodilators such as these (from first link):
  
  
  Coenzyme Q10
  L-arginine
  Magnesium
  Cocoa
  Garlic
  Niacin (nicotinic acid or vitamin B3)
  mint (which contains levomenthol)