The Role of Coffee in Heart Disease Risk

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Have you ever wondered if your coffee consumption impacts your heart health? The answer to this question could be in your genes! We each have some variation of the CYP1A2 gene, which determines how efficiently our bodies can break down caffeine. Some gene-coffee interaction studies have suggested that the effect of coffee on heart disease risk may be modified by a functional variant of the CYP1A2 gene. A recent study attempted to replicate the coffee-by-CYP1A2 interaction in terms of heart disease risk in a large population-based cohort. Today, we’ll be discussing what these researchers found as well as sharing some fast facts on caffeine.

What You Need to Know About Caffeine

Caffeine makes us feel alert by stimulating the nervous system. Many consume it through coffee, but caffeine is also present in energy drinks, some soft drinks, black tea, and some white, green and oolong teas. According to Health Canada, 400 mg of caffeine per day is considered a safe level for adults.  

People who are sensitive to caffeine can experience side effects like nervousness and rapid heart rate. Contrary to popular belief, caffeinated drinks like coffee will not dehydrate you. Caffeine in moderation is considered safe for the average healthy adult and may even boast some health benefits when included in a well-rounded, healthy diet. However, some research suggests that people with a functional variant at CYP1A2 may have an increased risk of heart attack and high blood pressure. 

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Does Coffee Increase Heart Disease Risk?

This study used data from the UK Biobank, a large prospective cohort study following over 500,000 adults over time to improve the prevention, diagnosis, and treatment of diseases of middle and old age. The UK Biobank included genome-wide genotyping of all participants and collection of a wide range of data from health and lifestyle questionnaires. For the present study, researchers took information on 347,077 participants’ coffee consumption, cardiovascular traits, and relevant covariates. Participants were categorized based on their daily coffee intake (i.e., non-drinkers, those drinking decaf coffee, and those drinking caffeinated coffee). Light coffee drinkers were defined as those consuming 1–2 cups/day, with heavy drinkers defined as those consuming more than 6 cups/day.

The results indicate a U-shaped relationship between habitual coffee intake and heart disease risk—that is, risk was lowest among participants drinking 1–2 cups/day, increasing for non-drinkers, decaf coffee drinkers, and heavy coffee drinkers. This study did not find that genetic variants modified the effect of coffee on heart disease risk. Slow caffeine metabolizers, however, did experience higher blood pressure, on average, compared to fast metabolizers.

These results cannot be generalized to everyone; however, the key takeaway is that heavy coffee consumption could increase your risk of heart disease. Whether your genes play a role is still being debated, so it’s best to limit your caffeine intake to just 400 mg per day.

Are you interested in learning about your genetic traits and how they might impact your nutrition? We now offer Nutrigenomix testing! Email us for more information.

Ryan Stallard