Caffeine could counteract the inflammation that comes with aging, a new study finds.
The difference could come down to just a few cups of coffee a day, study co-author and Stanford University professor of microbiology and immunology Mark Davis told Live Science. The study's findings may explain why coffee drinkers tend to live longer than those who do not drink coffee, the researchers suggested in a statement from Stanford University.
The study had a few parts: First, researchers analyzed data from more than 100 people who are taking part in an ongoing study, called the Stanford-Ellison cohort, which aims to investigate how the system changes during aging. The researchers reviewed the participants' blood samples, survey data and medical and family histories. [10 Interesting Facts About Caffeine]
The results showed that the older participants had higher levels of an inflammatory protein, called IL-1-beta, compared with the younger participants. What's more, among the older participants, those with higher levels of IL-1-beta had a greater risk of stiff arteries, high blood pressure and mortality during the study period, compared with those who had lower levels of this inflammatory protein.
To identify whether there was any causal link between IL-1-beta and conditions like high blood pressure, researchers then conducted a study on mice. The scientists found that injecting the mice with substances that increased the production of IL-1-beta triggered large amounts of inflammation and hypertension, supporting the idea of a cause-effect relationship, said Davis.
Next, researchers investigated why some older adults showed lower activation of the genes that encode IL-1-beta, and found an interesting correlation: The older participants who reported that they consumed more caffeinated beverages generally showed a lower activation of these inflammation-causing genes.
When researchers looked again at the blood samples of the older participants, they found that those whose blood had higher levels of caffeine and its breakdown products showed lower activation of these genes than participants whose blood had lower levels of caffeine and its breakdown products.
Researchers then turned to the laboratory again to confirm a cause-effect relationship. This time, they added caffeine into human immune cells growing in lab dishes, along with compounds that would trigger inflammation. Results showed that caffeine actually prevented these compounds from causing inflammation in cells. [10 Things You Need to Know About Coffee]
This finding may "explain why caffeine consumption correlates with lower blood pressure," Davis told Live Science.
The researchers noted in their study that lowering chronic inflammation in older people may prevent a number of age-associated diseases, including high blood pressure, stiff arteries and other cardiovascular problems, although more research is needed to confirm this.
For now, drinking coffee may be one way to decrease the inflammatory processes that naturally come with age, the researchers wrote in their paper.
But the researchers said they hope their work will spur other scientists to develop more sophisticated drugs that could target these culprits of inflammation.
Originally published on Live Science.