You are what you eat, even on a genetic level. What you consume can affect your DNA and your health. So how does that apply to coffee?
As one of humanity's primary caffeine sources, coffee is among the world's most popular drinks after tea—between 2015 and 2016, people consumed over nine billion kilograms of coffee. In this video, Trace Dominguez from DNews (Discovery News), a scientific YouTube channel, explained how our favorite pick-me-up can break your DNA.
In 1972, a study on coffee in Biophysical Journal found that caffeine binds to broken DNA, which occurs when there is a natural or chemical change in the strand. Iff caffeine were present during the formation of DNA, it could cause breaks in the chromosomes, threadlike structures that carry genetic information. That's why pregnant women usually shouldn't drink coffee, Dominguez said.
When DNA is broken by other processes, caffeine has a tendency to affect those broken pieces, which keeps them broken, he said. However, according to a March 2016 study in Molecular Nutrition and Food Research, drinking coffee also reduced naturally occurring DNA breakage by a third, and that reduction continued several hours later.
"So coffee or caffeine, really, can break DNA or keep it from being broken depending on when the coffee hits your DNA," Dominguez said.
While coffee's ability to break your DNA might sound drastic, DNA breakage is actually somewhat normal and can be caused by several factors, such as normal cell function or UV light.
The kind of coffee you drink is also part of the equation. Dark roast coffee fan experienced spontaneous DNA strand breaks less frequently than drinkers of other kinds of coffee, according to the European Journal of Nutrition.
Meanwhile, other studies have shown that coffee drinkers pass their habit onto their kids. In fact, there may be genes associated with drinking coffee. A mutation on the gene PDSS2, for example, is associated with drinking less coffee. And if coffee doesn't change DNA itself, it can contribute to epigenetic changes, or how gene function (rather than the genes themselves) change.
While it can affect your DNA, coffee can also have protective effects on a variety of ailments, including cardiovascular disease, Alzheimer's, Parkinson's, Type 2 Diabetes, some types of cancer, and sleep disturbances, Dominguez said.
So next time you drink a cup of coffee, think about how your parents consume it, and how your own kids might consume it. We can't say that it's necessarily good or bad for you based on the conflicting research. But coffee has more to do with our genes than we think.
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