Cigarette smokers tend to drink more coffee according to scientists. A study published last month has found that an inherited genetic variant that causes people to smoke more might also cause them to crave more caffeine.
You can have zero, one, or two copies of the variant in a gene called CHRNA5. The study found that each copy of the gene led to an increase in smoking of one more cigarette per day and 0.15 cups of coffee per day.
“You could extrapolate from that and say that if you smoked 10 cigarettes per day more than the next person, you would be drinking the equivalent of about one and a half extra cups of coffee per day,” Marcus Munafò, the lead researcher, told the New Scientist. He doesn’t know yet what the actual purpose of gene variant is, but the side effect shows up clearly in the data.
According to a 2014 study, smoking also blunts taste buds, especially for the bitters in caffeinated drinks. Some smokers might claim that the blunting is taste-enhancing, but coffee connoisseurs likely turn up their noses at such an excuse.