If you're a coffee lover, it might be partly because of your parents.
Researchers from UC San Diego found that some people are genetically predisposed to drink more coffee than others. They looked at data from DNA testing 23andMe and studied thousands of coffee drinkers' habits.
One of the lead researchers told NBC 7 that while it's not cut and dry, there's a clear link between certain genetic variants and how much coffee we drink.
"The amount of coffee that somebody consumes is partially influenced by genetics, which means that siblings will be similar to one another," Dr. Abraham Palmer, a professor in the UCSD School of Medicine Department of Psychiatry, said.
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High levels of coffee consumption were also associated with other types of drug consumption, according to the researchers.
"Too much of anything can be problematic, and what we identified is that people that drink excessive amounts of coffee also tend to take more drugs, alcohol, smoking," said Dr. Sandra Sanchez-Roige, an associate professor in the UCSD School of Medicine Department of Psychiatry. "By learning about how much people drink coffee excessively, we also hope to learn something about fundamental reasons why people overdrink or overconsume other substances."
Palmer says the researchers also found a link between coffee consumption and obesity.
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"People who drink a lot of coffee tend to be heavier than people who are genetically predisposed to drink less coffee," Palmer said.
Researchers say they combined their data with a similar study in the U.K., and the results weren't always the same. They say this is most likely due to environmental and cultural factors like the types of coffee Americans drink and the way they drink it.
