Coffee, lauded for its ability to keep drinkers awake and lively, is incredibly popular — estimates guess that 1.6 billion cups are drunk every day. 

new study may come as a rude awakening, pardon the pun, to a good number of these coffee dreinkers. According to the study, drinking 28 cups of the beverage or more per week increased a person's odds of dying prematurely by 21 percent. And in adults under 55 years old the quoted risk jumped 50 percent higher.

"There continues to be considerable debate about the health effects of caffeine, and coffee specifically, with some reports suggesting toxicity and some even suggesting beneficial effects," study co-author Dr. Carl Lavie, a cardiology researcher at the Ochsner Medical Center in New Orleans, said in a statement.

Lavie could be referring to a 2012 study published in the New England Journal of Medicine that found that people who drank four or five cups of coffee a day tended to live longer than those who only drank one cup (or no cups) of coffee. In men, their risk of death dropped 12 percent; in women it was 16 percent. Or perhaps the 2013 study that hypothesized that Greek coffee was the key to Ikarian longevity. 

But Lavie's research found data that contradicted — or at least complicated — these earlier studies.

For the study, Lavie and his colleagues tracked data from the Aerobics Center Longitudinal Study, which encompassed 43,727 participants. The researchers collected data via in-person interviews as well as medical examinations, including fasting blood chemistry analysis, anthropometry, blood pressure, electrocardiography, and a maximal graded exercise test, between February 3, 1971, and December 30, 2002.

During the 17-year median follow-up, 2512 deaths occurred, of which 32 percent were due to cardiovascular disease. In particular, the researchers observed that younger men and women showed a significant association between high coffee consumption and mortality rates. For scientists, these results are not surprising, as it has been known for some time that coffee has negative effects on the body due to its caffeine content. In studies, researchers have found evidence of caffeine's potential to inhibit insulin activity, and increase blood pressure and levels of homocysteine.

“On the basis of these findings, it seems appropriate to suggest that younger people avoid heavy coffee consumption,” write the authors of the current study.

Such restraint may not happen anytime soon. According to a NCA National Coffee Drinking Trends (NCDT) market research study, 83 percent of the U.S. adult population drinks coffee with 63 percent of Americans doing so daily. How many cups they consume is the real question.

Source: Lavie C, van Dam R, Lin YL, HuxleyR. Association of Coffee Consumption With All-Cause and Cardiovascular Disease Mortality. Mayo Clinic Proceedings, 2013.