Drinking Coffee May Be Genetically Driven, Analysis From Harvard Shows

Are you the type who needs an extra-large black coffee just to get to your 9 a.m. meeting, or does a single latte leave you bouncing off the walls? It turns out that either way, your genetics may be at least partially responsible for how you respond to caffeine.

A paper published on October 7 in the journal Molecular Psychiatry analyzed data from 120,000 coffee drinkers across dozens of studies to identify six gene variations that are connected to caffeine processing and coffee consumption. The analysis was undertaken by researchers from the Harvard School of Public Health and Brigham and Women’s Hospital.

Coffee and Health

Interestingly enough, the genetic influence does not appear to be linked to flavor preferences or taste.

“The genes we identified were predominantly related to caffeine and its metabolism,” said study leader Marilyn Cornelis, who is a research associate in the Harvard’s nutrition department. “We didn’t find gene variants related to taste.”

These genetic variations may account for some of the health benefits attributed to drinking coffee, as well as some of coffee’s potential downsides. Two variations were found near the genes BDNF and SLC6A4, both thought to be involved in the positive effects of caffeine. Others were near genes known to influence addiction and the metabolism of fats and sugars.

Those whose bodies were able to metabolize caffeine more quickly were more likely to be heavy coffee drinkers since, as Cornelis explained, they lose the effect of the caffeine more quickly.

Coffee drinkers were found to have higher blood sugar and cholesterol levels than those who don’t drink coffee, but lower blood pressure.

Subjects who had five or six of the variations were slightly more likely to drink coffee heavily (four or more cups per day) than those with only one or two variations.

The Next Steps

Cornelis, whose previous research has also focused on linking caffeine consumption to genetic codes, said that her next goal is to focus in on various studies with competing results on coffee’s positive or negative health impacts.

As recently as October 10, new research has shown that both caffeinated and decaf coffee can contribute to liver health, and coffee has previously been positively linked to weight loss, increased brain activity, and a reduced risk of Parkinson’s and dementia.

“Health wise, coffee is a huge benefit for certain types of cancer. You are less likely to have type 2 diabetes, Parkinson’s disease, and dementia. Business wise, coffee is the second most traded item in the world — it is a huge commodity and always in demand,” explains Ken Lathrop, President of Coffee Crafters.

The reality is that some people may react well to coffee, while others will not, based on their genetic composition.

“We’ve been bombarded with studies showing good and bad findings related to coffee,” said Cornelis. “But genes may account for these health differences among people that also lead some to drink coffee and others to abstain.”