Scientists are always searching for new ways to understand how the human body works, and a research team from the University of Toronto has discovered something surprising about coffee and kidney health. Led by researcher Ahmed El-Sohemy, the team found that the way coffee affects people depends largely on their genes.
At the center of the discovery is a gene called CYP1A2. This gene controls how quickly the body breaks down caffeine. You can think of it as an instruction manual that tells your body how fast to process the caffeine from coffee, tea, or energy drinks.
Some people have a version of this gene that works very quickly. Their bodies break down caffeine fast, so they can usually drink several cups of coffee without feeling strong effects. Others have a slower version of the gene.
In these people, caffeine stays in the body much longer, which can lead to stronger effects such as jitteriness, trouble sleeping, or added stress on the body.
The researchers found that this difference may also affect kidney health. For slow caffeine metabolizers, drinking too much coffee could increase strain on the kidneys over time. The kidneys play a vital role in filtering waste from the blood, balancing fluids, and maintaining overall health, so protecting them is very important.
The study suggests that about three cups of coffee per day is a safe amount for most people. Some individuals may tolerate four cups, but the right amount depends on their genetic makeup. Interestingly, about half of the population has the fast-processing gene, while the other half has the slow version.
There is even a genetic test that can show which type a person has. Knowing this information can help people make smarter choices about their caffeine intake and reduce potential health risks.
This research highlights how personalized nutrition may become more important in the future. Instead of one-size-fits-all advice, health recommendations may be tailored to each person’s genetic profile.
The findings were published in JAMA Network Open and add to growing evidence that genes influence how our bodies react to everyday foods and drinks. As scientists continue studying the connection between diet and genetics, people may gain more tools to protect their health and prevent disease.
Understanding how your body handles caffeine can help you enjoy coffee safely while taking care of your kidneys and overall well-being.
If you care about kidney health, please read studies about how to protect your kidneys from diabetes, and drinking coffee could help reduce risk of kidney injury.
For more information about kidney health, please see recent studies about foods that may prevent recurrence of kidney stones, and eating nuts linked to lower risk of chronic kidney disease and death.
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