Since at least the middle of the 15th century, people have been roasting and brewing coffee beans into the aromatic beverage enjoyed by billions of people today. But caffeine – and coffee in particular – has often come under scrutiny as health experts debated its impact on our health. In fact, as recently as 1991 the World Health organization included coffee in a list of possible carcinogens. But just 15 years later, further research showed that it did not increase the risk of cancer, and in fact could provide some protections against certain types of cancer. Today most researchers and health experts consider coffee to be a safe beverage, when consumed in moderation. But what does that mean for your health? And how much is too much?
Coffee is made up of thousands of different compounds, and the types of beans used, the way they are grown, harvested and roasted, and even the way the coffee is made can all affect the chemical makeup. The best-known component of coffee is caffeine – a natural stimulant that many of us rely on to get us going in the morning. But coffee also contains lots of other antioxidants and active ingredients that can actually boost your health. In fact, the latest research shows that coffee may help in more ways than you probably know, including:
- Lowering your risk of Type II diabetes. The polyphenols and minerals in coffee may help improve the way your body processes glucose and improve the effectiveness of insulin.
- Protect your heart health. The Nurses' Health Study – one of the largest studies into the risk factors for diseases in women – showed that women drinking four or more cups of coffee a day had a 20% lower risk for stroke compared to non-coffee drinkers in the study. A different study showed that consumer two-three cups of coffee a day reduced the risk of heart disease by 21%. However, the method of brewing coffee is important, since unfiltered coffee (such as French press) contains diterpenes – a substance that can increased LDL (bad) cholesterol and triglycerides. For better heart health, choose filtered (drip) or instant coffee.
- Reduce risk of some types of cancers. As noted above, rather than being a carcinogen, coffee can actually help protect against some kinds of cancers. Coffee may reduce inflammation, which is a risk factor for many types of cancer. And a study at Johns Hopkins found that female coffee drinkers had a 26% lower risk of colon cancer.
- Improve depression. A large study of more than 260,000 participants showed a 10% decrease in the risk of depression among those who drank coffee daily.
- Protect your liver. Research shows that liver enzyme levels are more likely to be in the healthy range in people who drink coffee. However, this seems to be true whether participants drank regular or decaffeinated coffee, so caffeine can't take all of the credit on this one.
- Reduce risk of Alzheimer's disease. The Cardiovascular Risk Factors, Aging and Dementia (CAIDE) study showed that drinking three to five cups of coffee a day for middle aged people was associated with a decreased risk of Alzheimer's disease later in life. However, additional studies are needed to deliver conclusive results. Studies have also shown that coffee consumption may reduce the risk of Parkinson's disease as well.
- Longer life. Several studies have indicated an association between moderate coffee drinking and a reduced risk of early death – up to 16% in some studies.
What's the Downside?
Unlimited quantities of caffeine isn't healthy, and some people should avoid coffee and caffeine entirely. In fact, most studies show that 400 mg of coffee a day is safe and appropriate for most people. That equates to four to five cups of brewed coffee, or about three to four cups of pour-over or cold-brew coffee. Consuming more than that may be fine for some people, but for others it can cause anxiety, jitters, insomnia, increased heart rate, or high blood pressure. And if you are pregnant or breast feeding, be sure to talk to your doctor about how much coffee or caffeine is safe for you to consume.
The bottom line is this: if you enjoy your morning (or early afternoon) cup of joe, there's no reason to stop and plenty of reasons to keep drinking it guilt free. As with most things, moderation is the key. But if you've never been a coffee drinker, or are sensitive to the effects of caffeine, there’s no reason to start drinking it now. You can live a perfectly healthy life and take plenty of other steps to reduce your risk factors for chronic disease with diet and lifestyle changes.
This article first appeared in the August 2023 edition of the HealthPerks newsletter.