Coffee and I have had a distant, distrustful relationship — that is, until recently. I was warned early of the “evils” of coffee. I saw how addictive coffee could be for some people, so I reasoned that it was better not to start. I live in Portland, however, where coffee is an important part of the culture.
My attitude changed the year my second daughter was born. I was so tired from lack of sleep and I thought some coffee would help. It certainly did! I was up until the wee hours of the morning, wide awake. I stayed away from coffee for a couple of months after that experience.
These days, I'm not really committed to being either a coffee drinker long-term or a coffee teetotaler. So, I thought I'd look into some of the studies on coffee, and here's what I learned.
Why you should drink coffee
1. Coffee and heart disease: Research presented in November 2017 at the American Heart Association’s Scientific Sessions linked drinking coffee to a lower risk of heart failure, coronary heart disease and stroke. Researchers said drinking coffee led to a "decreased risk of developing heart failure by 7 percent and stroke by 8 percent with every additional cup of coffee consumed per week compared with non-coffee drinkers," according to a news release. A 2019 study by the British Heart Foundation debunked some earlier studies that linked drinking coffee with hardening of the arteries that can lead to heart attack or stroke. The study found that even people who drink up to 25 cups of coffee a day don't have a greater risk of having stiffer arteries.
2. Coffee and life span: Two 2017 studies publishes in the Annals of Internal Medicine indicated that coffee drinking led to a longer life, and that it did so for multiple ethnicities. The first study, conducted by a team from the University of Southern California, found that higher coffee consumption among more than 215,000 participants in both white and non-white populations resulted in a lower risk of death due to heart disease, stroke, diabetes, cancer and kidney disease, among other conditions. The second study, led by the Imperial College London and International Agency for Research on Cancer, considered half a million Europeans from 10 different countries. Those who consumed three cups a day tended to live longer than non-coffee drinkers and saw a reduced risk of death from circulatory diseases and diseases related to the digestive tract. In both studies, decaf drinkers experienced the same results as those who drank regular coffee.
3. Coffee and cancer: Overall, coffee drinkers are found to have lower rates of certain cancers, including skin, colon, endometrial and prostate cancer. There is some discussion about whether coffee promotes estrogen-dominant breast cancers, but this 22-year follow-up paper found no link to estrogen-dominant breast cancer in pre-menopausal woman with either caffeinated or decaf tea and coffee intake. There was a slight correlation between breast cancer and post-menopausal women, however. A study by the World Cancer Research Fund International found a strong link between coffee consumption and a decreased risk of liver cancer. (Despite these findings, however, there are still some concerns about how coffee affects cancer risk, as noted in No. 3 under the "why maybe you shouldn't" section below.)
4. Coffee and diabetes: Another benefit to coffee drinkers (at least those who drink four cups or more per day) is a significant decrease in risk of developing Type 2 diabetes. Some research has pointed to three components of coffee for this effect: caffeic acid, chlorogenic acid and caffeine.
5. Coffee, dementia and Alzheimer's disease: Coffee also shows promise in decreasing risk of dementia and Alzheimer’s disease. One study found a decrease in Alzheimer’s risk with long-term caffeine exposure. Another found that consumption of coffee and tea were linked to lower risks of Alzheimer’s disease and dementia. For that study, about 1,4000 people in Finland and Sweden were followed for two decades, and those who reported drinking three to five cups of coffee daily were 65 percent less likely to develop dementia and Alzheimer's, compared with those who didn't drink coffee or only drank it occasionally. And, in case you were wondering, roasted coffee beans have the best brain-protecting elements.
6. Coffee and Parkinson's disease: There has also been a link to decreased risk of Parkinson’s disease among coffee drinkers. However, recent research cautions women taking replacement hormones against drinking coffee, as the two combined could increase your risk. There may be an explanation on why some people are protected from Parkinson’s disease when drinking coffee. About 25 percent of the population has a gene, GRIN2A, that appears to protect them from developing Parkinson’s disease if they drink coffee. If you don’t have that gene, you may not get the protective benefit of drinking coffee.
7. Coffee and aging: Caffeine may counter age-related inflammation. A study published in Nature Medicine found that older people with lower levels of inflammation — which is believed to contribute to conditions such as cardiovascular disease, cancer, diabetes, osteoarthritis, Alzheimer's, depression and more — also happened to be coffee drinkers. The more caffeine they drank, the more protected they were from this age-related inflammation.
8. Coffee and obesity. In a study published in Scientific Reports, scientists from the University of Nottingham discovered that drinking coffee can stimulate "brown fat," which could be the key to fighting obesity. Brown fat plays a role in how fast we burn calories. Researchers say more study is needed to see if caffeine or caffeine supplements can help with the activation of brown fat.
9. Coffee, depression and MRSA: If that wasn’t enough, some studies also show less depression in coffee drinkers and that coffee drinkers are to less likely to be carriers of the superbug, MRSA.
I don’t know about you, but this makes me want to go out and get an espresso. So what’s the holdup? Why do some doctors, health experts and nutritionists caution against drinking coffee? Here are a couple of reasons.
And why maybe you shouldn't ...
1. Coffee and pregnant women: The American College of Obstetricians and Gynecologists stated that moderate caffeine consumption — less than 200 mg per day, which is the amount in about 12 ounces of coffee — doesn't appear to have an impact on premature birth miscarriage, or fetal growth. The effects of larger amounts of caffeine during pregnancy are unclear.
2. Coffee and nutritional deficiencies: Coffee can block the absorption of certain minerals, including iron. This can obviously be a problem. But more then that, it is a powerful appetite suppressor for many. If you drink coffee instead of eating a well-balanced meal, you can end up with deficiencies of macro and micronutrients, which can lead to a host of problems. And don’t think that this appetite-suppressing effect will help you lose weight long-term, because you can turn down your metabolism rate when you don’t eat enough.
3. Coffee and cancer: As noted earlier, coffee drinkers seem to be generally safer from certain cancers. Yet there are also some concerns that coffee can actually increase cancer risk. In California, a judge ruled that coffee roasters and stores must include warning labels on coffee about acrylamide — a possible human carcinogen created when coffee beans are roasted. (According to the National Cancer Institute, acrylamide is "reasonably anticipated to be a human carcinogen," although it adds that studies "have found no consistent evidence that dietary acrylamide exposure is associated with the risk of any type of cancer" in humans.)
4. Coffee and sleeping issues, irritability, anxiety: If you are stimulating your body for a fight-or-flight response with coffee, sleeping won't be the most likely first response from your body, hence why many people suffer from sleep issues when they drink coffee. Caffeine can also make you shaky, irritable or anxious.
5. Caffeine and GABA metabolism: GABA (gamma-aminobutyric acid) is a neurotransmitter that's produced in the brain, nervous system and GI tract. It helps you with stress management and exerts a calming influence. I’ve taken it as a supplement to help me sleep before. Caffeine can prevent the binding of GABA to GABA receptors, which is another reason why caffeine can make some people feel more anxious.
6. Caffeine and metabolic syndrome: In a study published in the Journal of Agricultural and Food Chemistry conducted on mice, Australian researchers found that drinking more than five or six cups of caffeinated coffee a day increased the risk of metabolic system and led to weight gain.
What's the right answer for you?
This is where I am now on the coffee issue: Coffee is a highly sprayed crop, so I almost always buy an organic brand to avoid a high pesticide residue. Coffee, in my mind, should also be bought fair-trade as workers are often abused in the industry. This makes coffee much more expensive, which also limits my coffee drinking.
As for coffee and health, I've had a lot of issues with overwhelming tiredness in the past. While coffee could have helped me survive some hard days more easily, I took the hard route and rebuilt my health using food and nutrition. It was worth it.
Coffee should never be a substitute for good energy caused by good health. (When I was writing my salad cookbook, I got such a huge energy boost from all the salads I was stuffing my face with all day, that I didn’t even want to drink regular coffee — I didn’t need any more energy!)
To get all the benefits coffee has to offer, it seems you have to drink a lot of it. Yet, if you drink too much, then you risk health problems. A 2019 study in The American Journal of Clinical Nutrition that analyzed 347,077 coffee drinkers found that five cups of coffee is the most you should drink in a day.
"In order to maintain a healthy heart and a healthy blood pressure, people must limit their coffees to fewer than six cups a day - based on our data six was the tipping point where caffeine started to negatively affect cardiovascular risk," said researcher Professor Elina Hyppönen of the Australian Centre for Precision Health, in a statement.
So, for now, I am enjoying coffee on a somewhat regular schedule, but not every day or even every week. I'm definitely not drinking enough to reap the health benefits found in the above studies, but I drink it for the enjoyment. Whatever your situation, I hope you've found a good balance, too.
Editor's note: This story was originally published in May 2012 and has been updated with new information.