Every year on 1 October, the world comes together to celebrate coffee. Coffee has never been more popular, with an estimated 3 billion cups consumed every day. But is coffee good or bad for you?
How does it work? Coffee contains caffeine. Caffeine works by stimulating the central nervous system (CNS), heart, and muscles. Coffee also contains other chemicals that might have other benefits.
However coffee containing caffeine can cause insomnia, nervousness and restlessness, stomach upset, nausea and vomiting, increased heart and breathing rate, and other side effects. Consuming large amounts of coffee might also cause headache, anxiety, agitation, ringing in the ears, and irregular heartbeats.
Drinking unfiltered coffee can increase total cholesterol, low-density lipoprotein (LDL), and levels of another type of blood fat called triglycerides. This might increase the risk of developing heart disease. Using coffee filters helps to reduce these effects on cholesterol.
There is some concern that drinking more than 5 cups of coffee per day might not be safe for people with heart disease. But for people who don’t have heart disease, drinking several cups daily does not seem to increase the chance of developing a heart problem.
Coffee has been around for a long time and blamed for many ills — from stunting your growth to causing heart disease — but newer research shows that it may actually have health benefits.
People most commonly drink coffee to relieve mental and physical fatigue and to increase mental alertness. Coffee is also used to prevent Parkinson’s disease, Alzheimer’s disease, dementia, and cognitive decline. It can also help to prevent gallstones, gout, type 2 diabetes, and certain types of cancer.
Some studies have found an association between coffee consumption and decreased overall mortality and possibly cardiovascular mortality, although this may not be true in younger people who drink large amounts of coffee.
Why the apparent reversal in the thinking about coffee? Earlier studies didn’t always take into account that known high-risk behaviours, such as smoking
and physical inactivity, tended to be more common among heavy coffee drinkers.
Studies have shown that coffee may have health benefits, including protecting against Parkinson’s disease, type 2 diabetes and liver disease, including liver cancer. Coffee also appears to improve cognitive function and decrease the risk of depression.
However, the research appears to bear out some risks. High consumption of unfiltered coffee (boiled or espresso) has been associated with mild elevations in cholesterol levels.
In addition, some studies found that two or more cups of coffee a day can increase the risk of heart disease in people with a specific — and fairly common — genetic mutation that slows the breakdown of caffeine in the body. So, how quickly you metabolize coffee may affect your health risk.
Although coffee may have fewer risks compared with benefits, keep in mind that other beverages, such as milk and some fruit juices, contain nutrients that coffee doesn’t. Also, adding cream and sugar to your coffee adds fat and calories — up to hundreds of calories in some cases.