The Science Behind Hangovers and Prevention

By Wendy Bacigalupi-Bednarz, Editorial Contributor

Holiday parties are upon us and for many these festivities include alcoholic beverages. Whether you’re gulping eggnog laced with rum or sipping one of the season’s trendy cocktails, you may be headed for a hangover.

Those symptoms — headache, fatigue, thirst, dizziness, nausea and a loss of appetite — occur once alcohol has left the body. While drinking in moderation, or not at all, is the best way to avoid hangovers, scientific studies have identified types of alcoholic beverages that are likely to cause more severe symptoms, says Orlando Health registered dietitian Lauren Popeck.


The main active ingredient in alcoholic beverages is ethanol, which is made through distilling and fermenting. These processes also create toxic by-products — known as congeners — that include methanol, isopentanol and acetone. 

Numerous clinical studies have shown that alcoholic beverages containing high amounts of congeners may increase the likelihood and intensity of hangover symptoms as compared to beverages with low amounts. Drinks with low congener levels typically are clear beverages.

Drinks with High Congener Levels

  • Cognac/Brandy
  • Red Wine
  • Dark Rum
  • Tequila
  • Whiskey and Bourbon Whiskey

Drinks with Low Congener Levels

  • Vodka (has nearly no congeners)
  • White Wine
  • Gin
  • Light Rum
  • Certain Beers

More science-backed tips

Popeck also suggests reducing the symptoms and severity of hangovers by: 

  • Eating a healthy meal when drinking. This helps slow the rate that alcohol gets into your system. Aim for healthy proteins such as tuna or salmon, which contain B vitamins, to promote metabolism and eliminate alcohol from your body. 
  • Avoiding salty foods, which increase thirst and lead you to drink more.
  • Drinking water with alcohol to alleviate its dehydrating effects. Try mixing half a glass of wine with seltzer, or a tall mixed drink with only one shot of liquor plus double the club soda, or simply drinking a glass of water between each cocktail.
  • Reaching for potassium-rich foods the next day. Cantaloupe, kiwi or bananas can help replenish electrolytes lost due to increased urination. Potassium also will help reduce dizziness and lethargy. Plus, fruits contain healthy carbs that counteract alcohol-induced low blood sugar.