Is drinking decaffeinated coffee just as good for your health?

Use Chemex brewing (Chemex pour-over method) to make coffee.

Some people think that drinking coffee is a "bad habit" that needs to be corrected. In an article on Monday, I reviewed the evidence about coffee drinking and health to clear up these misunderstandings.

In this regard, readers have made a lot of comments and raised a lot of questions. Therefore, we decided to pick out some of the most representative questions to answer, which may be helpful to you.

Is drinking decaffeinated coffee just as good for your health?

Most studies did not include data on decaffeinated coffee, perhaps because too few people drank the coffee, or because the data were not available. Only a few studies included data on this type of coffee, but did not produce consistent results. Decaffeinated coffee does not seem to protect against cardiovascular disease as regular coffee does. A meta-analysis of stroke shows that decaffeinated coffee has the same preventive effect as regular coffee. Two analyses of breast cancer showed that decaffeinated coffee and regular coffee had no effect. Decaffeinated coffee also protects against lung cancer, but has little effect on Parkinson's disease; decaffeinated coffee plays a role in preventing diabetes and reducing overall mortality, but may be slightly weaker than normal coffee.

But most studies lack relevant data. Our conclusion is that, overall, there is little evidence of the potential benefits of decaffeinated coffee, but there is no evidence that it is harmful.

How much capacity does a cup of coffee mean?

Almost all studies define a cup of coffee as an 8-ounce serving. I think it's a little less than most people usually drink. The grande-size coffee in Starbucks is 16 ounces.

Is drinking tea as beneficial as drinking coffee?

There is as much literature about tea as about coffee, and it takes a lot of time to go through them thoroughly, and it doesn't seem to take so much trouble for this column. However, some of the studies I reviewed earlier did include tea in the analysis, so I'll give you a brief introduction. People who drank more tea had a lower risk of Parkinson's disease and cognitive impairment. Black tea may prevent diabetes, but it is not statistically significant. There is no correlation between green tea and diabetes.

Is drinking coffee good for your health because of caffeine or other ingredients in coffee?

It's not clear yet. In my opinion, the ingredients that play a preventive role in different diseases may not be the same. For example, for many neurological problems, caffeine may play a role as a brain stimulant. My hypothesis is based on facts: both coffee and tea can prevent these problems, while decaffeinated coffee does not. However, for some other diseases, drinking other caffeinated drinks did not show the same benefits. No one has ever suggested that drinking diet soda is associated with a reduced risk of cancer. In addition, decaffeinated coffee can also prevent some diseases. So there's probably something else at work, but we don't know exactly what it is.

So, does drinking coffee have any effect on high blood pressure or cholesterol?

A 2005 meta-analysis found that caffeine was associated with elevated blood pressure in randomized controlled trials. However, when caffeine comes from coffee, it has little effect on blood pressure. A 2011 study found that the blood pressure-boosting effect of caffeine intake lasted at least three hours. However, there was still no significant correlation between long-term coffee consumption and higher blood pressure. A 2012 meta-analysis included 10 randomized controlled trials and five cohort studies and found that coffee consumption had no significant effect on blood pressure or high blood pressure.

But, as the New York Times once reported, two studies have shown that drinking unfiltered coffee, such as Turkish coffee, can lead to an increase in serum cholesterol and triglycerides. However, filtering coffee with filter paper seems to remove caffeine, a cholesterol-raising substance.

High blood pressure and high cholesterol attract people's attention because they can lead to heart disease and even death. Drinking coffee is good for all these problems, which is the crux of the problem.

I forgot to mention the harmful effects of caffeine, which made some readers unhappy. So what is the relationship between coffee drinking and nervousness and mood changes?

I would like to reiterate that the argument of this article is not to advise everyone to drink coffee. As I said in a recent article on dietary advice, I don't think it makes sense to point and judge other people's food and drink. Moreover, all the above are epidemiological evidence, that is to say, they are patterns found in observational studies. Until we get evidence from randomized controlled trials, I don't want to easily advise people to change their current eating behavior, because this advice may be wrong.

This article just wants to point out that there is no evidence that coffee is harmful to ordinary people. Some people think that we drink too much coffee, but the available data do not support this view. Coffee has nothing to do with health damage-in fact, just the opposite. In view of this, we should no longer stop people from drinking coffee, or tell coffee drinkers what to do, nor should we feel ashamed or think we should refrain from drinking coffee.

Of course, if drinking coffee makes you feel uncomfortable, that's another matter. As I have said before, when it comes to nutrition, it may be necessary to make trial and error according to the specific situation of the individual. Some people can't take caffeine for medical reasons, so they shouldn't drink coffee. If drinking coffee makes you feel uncomfortable, makes it difficult for you to fall asleep, or makes you an unlikable person, you can drink less or no coffee.

But if you like coffee, enjoy it as much as you want.