Coffee and consumer health: good-news research
By Rose Simone
Good news for coffee drinkers: It’s good for you!
By Rose Simone
David Furman has upped his single shot of espresso to a double shot.
He has always enjoyed coffee, and as a medical researcher, he was aware of studies showing its possible health benefits. But after leading a recent Stanford University School of Medicine study that pointed strongly to a link between coffee and heart health, Furman became convinced that more of this dark, rich brew is better than less.
“Now I’ll drink the double espresso in the morning and again after lunch. I’ll take it black,” he says.
The study he led, published in Nature Medicine in January this year, wasn’t initially about coffee. It was about the age-related systemic inflammation that seems to be associated with cardiovascular disease in some older people. But in the process of looking at what might reduce that inflammation, researchers found that the answer could be found in a cup of coffee.
Systemic inflammation is now being implicated “as a basic mechanism in most, if not all, diseases related to aging,” Furman said. That includes high blood pressure and heart disease, Alzheimer’s, dementia, arthritis and even many types of cancer.
Furman says when he talks about inflammation he doesn’t mean the kind of inflammation you might see if you have a cut or a wound. That kind of temporary inflammation is actually an important part of the body’s repair process. But chronic, systemic inflammation that happens inside the body as it responds to long-term, ongoing assaults from the environment and what we ingest has a sinister side.
When we are young, our bodies are very good at coping with inflammatory triggers, Furman says. “But as we age, our metabolic plasticity starts to shrink,” and this inflammatory process is no longer well regulated.
The body’s response is to send inflammatory proteins constantly coursing through the blood and replacing normal tissue with scar tissue. Ultimately that’s bad for the body’s organs. “We can measure it in the blood and we can also see it in cells that are exposed to an inflammatory milieu,” he says.
The researchers did an extensive analysis of data that was gathered from both young and old people enrolled in a long-term program known as the Stanford-Ellison cohort that started over 10 years ago. The program involved collecting data on over 100 people, both young and old, in the form of blood samples, surveys and medical and family history.
The researchers were particularly interested in the blood samples of two groups of older people, one group showing a high level of a particular inflammatory protein called Interleukin 1 beta in their blood samples, and the other group with very low levels of it.
They found individuals in the “high” group were much more likely to have stiff arteries, a risk factor for cardiovascular disease. The high group also had increased activity of free radicals, which can harm cells.
So how did all this lead to the coffee connection? Well, says Furman, the researchers knew of a molecule called adenosine (related to adenine, one of the building blocks of DNA) that can trigger this inflammatory process. They also knew, from previous studies, that coffee can actually block the effects of adenosine.
Intrigued, they began looking for the coffee connection in their survey data, and there it was, clear as day. People who were coffee drinkers had lower blood pressure, fewer cardiovascular problems and were living longer.
Furman was surprised by how clear the link was. “It was a pretty outstanding result,” he says. “It was linear and simple. Those with more caffeine intake had the lowest level of inflammation.”
Better still, he says, it shows up “in vitro,” in the petri dish. They found that incubated cells that had caffeine and its breakdown products in the mix showed significantly less inflammation when the inflammatory agents were added than those that didn’t.
The Stanford study is not the only one showing the benefits of coffee.
Eric Yoshida, professor of medicine at the University of British Columbia and chair of the Canadian Liver Foundation’s medical advisory committee, says coffee appears to reduce the risk of liver cirrhosis (scarring of the liver tissue) as well as liver cancer.
Once again, researchers think that caffeine may help reduce the effects of adenosine, which is also implicated in liver scarring.
Yoshida says what’s amazing is that the studies are all pointing in the same direction. “There are many studies that show a beneficial effect to drinking coffee and none so far that show a harmful effect on the liver,” Yoshida says. “For the liver at least, it seems more coffee is better.”
The studies indicate that to get this beneficial effect, you have to drink at least two cups of coffee a day, he adds. In Vancouver, where he lives, “that’s par for the course.”
Exactly how the coffee is working to protect the liver is not entirely known “because coffee is such a complex organic brew, which is why it is so wonderful,” he adds.
Both Furman and Yoshida add a few cautions. Overdosing on caffeine can mess with your sleep. Furman adds that people with some pre-existing conditions like inflammatory bowel disease need to watch it, because coffee can irritate the gut. Yoshida cautions that just because coffee protects against cirrhosis, you can’t assume that you can therefore drink more alcohol. “Alcohol is just generally bad for the liver,” he says.
They both strongly caution against the extra-large double caramel mocha fully loaded with a lot of sugar and cream on top and 300 calories. “If you start adding all these extra things like sugar or saccharin, that’s bad,” Furman says.
But if you are just a simple non-nonsense coffee drinker, these studies should put a smile on your face as you brew your morning pot. At a time when we are typically inundated with news about favourite foods and drinks that are bad for us, “it’s great that something we actually enjoy can help us achieve better health and quality of life,” Furman says.