▎ WuXi AppTec content team editor
Coffee is one of the most popular drinks in the world. Especially among young people, it is welcomed by more and more people, and it is a "life-sustaining artifact" for many people who stay up late and work overtime, relying on it to refresh their minds and improve work efficiency.
As scientific research progressed, scientists discovered that coffee is not only a delicious drink, but also has excellent health properties. But at the same time, scientists have also found that "excessive" coffee drinking can also bring health hazards.
So how much coffee is safe to drink per day? What are the health benefits of drinking coffee in moderation? What are the dangers of drinking too much? Today, let's take a look at it together.
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How much coffee is safe to drink per day?
Coffee contains a variety of bioactive compounds, such as the most important ingredient, caffeine. The coffee mentioned in this article mainly refers to coffee containing caffeine.
According to the European Food Safety Authority (EFSA), coffee is the main source of caffeine for adults, accounting for 40%-94% of total intake. In addition, coffee also contains chlorogenic acid, polyphenols, flavonoids, potassium, magnesium, vitamin E and other ingredients.
Both the U.S. Food and Drug Administration (FDA) and the European Food Safety Authority recommend that adults consume no more than 400 mg of caffeine per day. During pregnancy and lactation, the daily intake is best controlled within 200 mg.
Typically, 1 cup of espresso (60 ml) contains approximately 80 mg of caffeine and one cup of filtered coffee (200 ml) contains 90 mg of caffeine.
That is to say, adults should not drink more than 5 cups of espresso per day (300 ml), and pregnant and lactating women should not drink more than 2.5 cups of espresso per day (150 ml). Adults should not drink more than 4.5 cups of filtered coffee per day (about 889 ml), and pregnant and lactating women should not drink more than 2 cups of filtered coffee per day (about 445 ml).
What are the benefits of drinking coffee in moderation?
Multiple studies have found that drinking caffeinated coffee is associated with a reduced risk of morbidity and mortality for a variety of diseases.
01
May reduce the risk of Parkinson's disease
In 2010, a study published in the Journal of Alzheimer's Disease found that coffee drinkers had a 25 percent lower risk of Parkinson's disease compared to coffee-not drinkers; every 300 mg increase in caffeine intake was associated with a 24 percent lower risk of Parkinson's disease.
In 2020, a study published in Neurology found that even in people carrying mutations in the LRRK2 gene, one of the main causative genes for Parkinson's disease, drinking coffee was associated with a reduced risk of developing Parkinson's disease.
In addition, studies have found that drinking coffee may help people with more severe Parkinson's disease to better control their movements.
02
May reduce the risk of type 2 diabetes
Although studies have found that drinking coffee may raise blood sugar and insulin levels in people with diabetes, for people who do not have diabetes, regular coffee drinking is associated with a reduced risk of developing diabetes.
In 2014, a study published in Diabetologia followed 123733 participants for up to four years.
The findings showed that drinking 1 cup of coffee per day was associated with an 11% lower risk of developing type 2 diabetes compared to participants who drank no change in the number of coffees per day during the follow-up period, while drinking at least 1 cup of coffee per day was associated with a 17% increased risk of developing type 2 diabetes.
03
May have a protective effect on the liver
In 2017, a study published in the World Journal of Hepatology found that drinking coffee had a protective effect on the liver, appeared to reduce the risk of liver cancer and potentially slow the progression of chronic liver disease.
In 2021, a study published in BMC Medicine showed that compared with people who did not drink coffee, regardless of the type of coffee they drank (ground, instant, etc.), they were associated with a reduced risk of developing and dying from chronic liver disease, including a 21% lower risk of chronic liver disease and a 49% lower risk of death; a 20% lower risk of liver steatosis; and a 20% lower risk of hepatocellular carcinoma.
Moreover, people who drank ground coffee benefited more than people who did not drink coffee, such as a 36% lower risk of developing chronic liver disease and a 63% lower risk of death; a 36% lower risk of chronic liver disease or liver steatosis; and a 38% lower risk of hepatocellular carcinoma.
04
May be good for the heart
In 2021, a study published in circulation: Heart Failure, a journal of the American Heart Association (AHA), found no significant difference in the risk of heart failure in people who drank 1 cup of coffee a day compared to those who did not drink coffee; compared with those who drank 2 cups of coffee per day, the risk of heart failure was reduced by 31 percent; and those who drank at least 3 cups of coffee per day had a 29 percent lower risk of heart failure.
In addition, a study published in jama cardiology, the Journal of the American Medical Association, found no significant association between coffee drinking and arrhythmias.
05
May be beneficial for the brain
In 2021, a large study published in the Public Science Library of Medicine (PLOS Medicine) found that drinking coffee was associated not only with a reduced risk of two neurological disorders that affect brain health— stroke and dementia— but also with a reduced risk of dementia after stroke.
The study showed that drinking 0.5-1 cups, 2-3 cups, and ≥ 4 cups of coffee per day was associated with a 10%, 12%, and 8 percent reduction in stroke risk compared to people who didn't drink coffee; and a 6%, 7%, and 4 percent reduction in dementia risk, respectively.
At the same time, studies have found that drinking coffee can improve energy balance and help weight management; promote dopamine secretion, make people feel happy, promote mental health, and reduce the risk of depression; and also be associated with a lower overall risk of death.
Scientists have analyzed that coffee contains hundreds of compounds, some of which, or combinations of some, are thought to have health benefits. However, exactly which ingredients, and how they work to promote health, is not yet clear, and further research is needed.
Since there are so many health benefits to drinking coffee, isn't it better to drink as much as possible? Of course not, drinking too much coffee is not only not good for health, but also brings some harm.
What are the dangers of drinking too much coffee?
Excessive caffeine intake can trigger anxiety, restlessness, nervousness, restlessness, insomnia, hyperexcitement, psychomotor agitation, and poor thinking or language. Studies estimate that caffeine intakes above 1200 mg produce toxic effects, and intakes of 10,000 mg to 14,000 mg are more likely to be fatal.
Drinking more affects sleep
Drinking more coffee may affect sleep. Caffeine is a stimulant that keeps people awake, even when they want to fall asleep. For people with sleep difficulties, coffee should not be drunk again in the afternoon and evening.
Drinking more increases anxiety
Drinking caffeine can make people feel nervous or anxious, especially if you drink more coffee. The National Institute of Mental Health believes that anyone with anxiety disorders should avoid caffeinated coffee because caffeine can worsen symptoms, including excessive worry and nervousness.
Drinking more affects the health of fetuses, infants and young children
The fetus and infant's body breaks down caffeine more slowly, so women who are pregnant and nursing may drink more coffee may endanger the health of the developing fetus and infant.
At the same time, the American Academy of Pediatrics recommends that children should not drink coffee because they are more susceptible to the effects of caffeine, which is harmful to health.
Drinking too much may affect digestive health
Since the taste of caffeine is bitter, bitter foods or drinks cause the body to produce more stomach acid. Therefore, for people with esophageal reflux disease, drinking more coffee may worsen symptoms.
Drinking more may increase the risk of dementia
In 2021, a study published in Nutritional Neuroscience found that coffee intake was associated with a decrease in brain volume, and the more you drank, the more your whole brain volume decreased. Drinking more than 6 cups of coffee per day was associated with a 53% increased risk of dementia compared to people who drank 1-2 cups of coffee per day. But at the same time, studies have also found that not drinking or drinking coffee with low caffeine content also slightly increased the risk of dementia.
It should be noted that each person's physical condition is different, the tolerance to caffeine is also different, if there is a heart rate and breathing speed, insomnia, irritability, headache, stomach discomfort and other symptoms, is the body in the prompt to drink too much, should pay attention to reduce.
All in all, drinking coffee in moderation is good for health, and excessive amounts will be harmful to health.
For some people, such as people who have difficulty sleeping, people who will feel uncomfortable after drinking coffee, they should pay attention to drinking less coffee to avoid the harm of coffee to health.
For people who drink coffee regularly, it should be noted that although there are more and more studies that find that drinking coffee is beneficial to health, drinking coffee cannot be used as the only way to reduce the risk of disease, and the health of the overall lifestyle should be paid attention to; at the same time, when drinking coffee, it is necessary to reduce the intake of added sugar, if too much sugar is added, it will also endanger health.