Every second, 26,000 cups of coffee are drunk around the world. That’s more than two billion cups of coffee consumed every day. Yet most of us think of coffee as unhealthy. If coffee is your guilty pleasure you’ll be pleased to hear you can forget the guilt: coffee is good for you.
We’ve known for a long time caffeine is a very effective stimulant; it can wake you up, keep you alert and help you concentrate. Of course we also know that coffee is addictive and it’s not surprising we consider addictions to be bad for us. Caffeine is the world’s most popular drug.
But coffee is more than just caffeine. It’s actually chock-a-block full of different compounds, some of them with important health benefits. Some act as antioxidants, others reduce inflammation, and still others regulate insulin (the hormone involved in diabetes).
![The life cycle of the humble coffee bean. But could it be that coffee could extend your life? Image credit : Thomas [CC BY 2.0] via Flickr.](https://espressoscience.files.wordpress.com/2014/09/coffeelifecycle.jpg?w=960&h=720)
The life cycle of the humble coffee bean. But could it be that coffee could extend your life? Image credit : ‘Thomas’ via Flickr.
Are you sure coffee isn’t bad for me?
The first thing you’ll be pleased to hear: research published in 2008 found no link between drinking coffee and an increased risk of dying. This study followed about 130,000 people in their 40s and 50s for around 20 years. These volunteers were part of the Nurses’ Health Study (all female) and Health Professionals Follow-up Study (all male).
The researchers collected detailed health information about the volunteers, including their diet and coffee-drinking habits. At the same time they kept records of who died during the study. Even people drinking six cups of coffee a day were not at higher risk of death.
Could it really be good for me?
It gets even better. Not only will coffee not kill you, it may even protect you from a whole heap of nasty illnesses.
For example, research indicates coffee consumption reduces the risk of lethal prostate cancer in men. Drinking one to three cups of coffee a day (either normal or decaf), was linked to a 30% decreased risk of this cancer. Coffee also appears to reduce the risk of liver cancer by up to 40%.
Coffee drinking also reduces the risk of type 2 diabetes. Not only that, but within limits, the more coffee you drink, the lower your risk. Three to four cups of coffee a day was associated with a 25% reduced risk of developing type 2 diabetes, compared with people who drank fewer cups each day. Another study found that each additional cup of coffee reduced the risk by a further 7 or 8%. And in type 2 diabetes sufferers, drinking coffee reduced the risk of dying during a 20-year period by 30%.
What about for my brain?
A study published in 2012 followed 124 individuals aged 65–88 years. All of these people were showing the first signs of forgetfulness that commonly leads to Alzheimer’s disease. The researchers measured levels of caffeine in the blood and assessed their brain function over two to four years. Not only was coffee drinking not associated with decreased brain function, people with not much or no caffeine in their bloodstream were much more likely to have progressed to Alzheimer’s than people who had three cups’ worth of caffeine in their system.
Similarly, coffee drinking improves our long-term memory. Researchers found caffeine significantly reduced rates of forgetting over a 24-hour period. And moderate caffeine intake reduces your risk of getting Parkinson’s disease by somewhere between 30 and 60%.
Why the bad rap?
Despite all of this, we all know coffee has a bad name. This is likely to be because of other behaviours that go hand-in-hand with coffee drinking. People who drink a lot of coffee often smoke, may not exercise very much and tend to have a more unhealthy diet in general. As a result, a lot of early studies that concluded coffee was bad may have been reporting on confounded results. This means it was the smoking, lack of exercise or diet that was to blame for poor health, not the coffee drinking.
Can you drink too much coffee?
But of course too much coffee may still not be a great idea.
If you’re drinking so much coffee that you get tremors, have sleeping problems, or feel stressed and uncomfortable, then obviously you’re drinking too much coffee. Dr Rob van Dam, Harvard School of Public Health
And if you’re pregnant, it’s probably still wise to avoid or limit your coffee intake. We don’t have a complete picture of the effects of coffee on the foetus, but we do know that caffeine can cross the placenta and that a foetus is not very good at breaking the caffeine down.
Unfortunately, all of this is terrible news for yours truly. I’m one of a small group of people actually allergic to caffeine. But for most of my fellow Melbournites: drink up, now you’ve got a whole lot more reason to enjoy your latte.
Dr Jen Martin 
Except for the fact that if you drink heaps of coffee all the time you become a nervous wreck and permanently stressed due to all the cortisol in your bloodstream. Don’t get me wrong – I love coffee – but you need to moderate your consumption despite some of the benefits (and apparently you should also moderate your blogs about the benefits of coffee) 🙂 see -> http://stress.about.com/od/stresshealth/a/caffeine.htm
Many thanks for the useful link Howard. And yes, I totally agree. Exactly as I said in the post, if any amount of coffee is having a bad effect on you (whether that be anxiety, sleep problems etc), it is too much for you!! Moderation will mean different things for different people. But the results in the primary scientific literature are very clear – coffee (and not just caffeine) have multiple health benefits too. Thank you for reading and commenting.
Great read, Jen.
I’m curious to know if there are there any data that has assessed the health effects of the little extras most people add to their coffee. Are people who prefer lattes etc at greater obesity risk than, say, an espresso drinker? What about sweet–toothed coffee fiends as compared to those who eschew sweeteners? It isn’t too much of a stretch to consider those who regularly imbibe the industrial sized Starbucks type ‘coffees’ may be at greater risk.
Hi Bobbi,
Many thanks for reading and for your question. I think you are spot-on in your comments. Someone who is consuming their coffee as a Starbucks Frappachino with whipped cream is obviously getting a huge whack of their daily calories in that one drink. If they don’t take into account that the drink has enough calories to replace a whole meal they are obviously at huge risk of weight gain. I haven’t read any specific studies about that issue but they are sure to exist. Most of the papers I read suggest that black or white coffee is fine, just don’t add sugar or anything else!
There is also some evidence that coffee can raise your bad (LDL) cholesterol levels because of a substance called carestol. One way to get around this is to brew your coffee with a paper filter because the cafestol is in the oily fraction of the coffee and gets left on the filter. But on balance, coffee (when taken into account in a balanced diet) has many more healthy benefits than potential costs.
How do you like your coffee? Cheers, Jen
Another case where moderation is the key.
I’m an espresso drinker when I drink coffee Jen but my preference is for tea as it offers so much more variety!
Yes, as in most things. I’m a herbal tea drinker and the variety there is amazing. People often say they feel sorry for me that I don’t/can’t drink coffee but I can’t say it’s the slightest problem!
Great to see such good news posts 😉
Thanks for reading Jon!
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