Coffee is one of the most popular drinks in the world, and many people enjoy several cups a day. But how your body handles caffeine might play a big role in whether coffee is good or bad for your kidneys.
A recent study by scientists from the University of Toronto and other institutions looked at how heavy coffee drinking affects kidney health and whether your genes make a difference.
The researchers focused on a gene called CYP1A2. This gene helps control how fast your body breaks down caffeine. Some people break down caffeine quickly, while others do it slowly. These differences can affect how coffee impacts your body.
To make this clearer, think of two friends: Alice and Bob. They both love coffee and drink several cups every day. However, Alice’s body processes caffeine slowly, while Bob’s body clears it quickly. Because of this difference, the caffeine stays in Alice’s system much longer than in Bob’s.
The study found that people like Alice—slow caffeine metabolizers—who drink a lot of coffee, have nearly three times more signs of kidney problems than people like Bob.
These signs include high levels of protein in the urine, high blood pressure, and changes in how well the kidneys filter blood. These are all warning signs of potential kidney damage.
There has been some debate about coffee’s effect on kidney health. Some studies say it might protect the kidneys, while others say it could be harmful. This new study adds another piece to the puzzle: the way your body processes caffeine matters.
The researchers looked at people who drank more than three cups of coffee a day—about 300 milligrams of caffeine. This is close to the recommended daily limit in places like Canada and the U.S., where 400 milligrams per day is considered safe. But the effect of that caffeine depends a lot on how fast your body can clear it.
The research showed that among heavy coffee drinkers, the ones who were slow caffeine metabolizers had more signs of kidney strain.
These included albuminuria, which means too much protein in the urine, hyperfiltration, which means the kidneys are working too hard, and higher blood pressure. These problems can lead to kidney disease if not managed properly.
About half the population has the slow caffeine metabolism gene. This means many people may be at higher risk when they drink too much coffee.
Because of this, some clinics and companies now offer gene testing for CYP1A2. This can help people understand how their body handles caffeine and make better choices about how much coffee they should drink.
This study, led by researcher Ahmed El-Sohemy and published in the journal JAMA Network Open, shows why personalized nutrition is important. It means making food and drink choices based on your own body and genes, instead of general advice that may not fit everyone.
For coffee lovers, this research is a reminder to listen to your body—and maybe even learn a little about your genes. If you often feel jittery or have trouble sleeping after coffee, you might be a slow metabolizer. And if you’re drinking a lot every day, it could be putting stress on your kidneys.
Knowing more about your genes can help you make smarter choices about your health. This is a big step toward a future where healthcare is tailored to each person, leading to better health and fewer risks.
If you care about kidney health, please read studies about High blood pressure drugs may affect kidney health and findings of Effective home remedies for kidney infections.
For more health information, please read studies about important cause of kidney disease and Cruciferous vegetables may reverse kidney damage in diabetics.
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