Research shows that it may generally be good, but there are exceptions.

Key points

• Coffee contains polyphenols, vitamins, and minerals that are good for our body and the brain.
• There is not much consensus on how many cups per day can be beneficial.
• Coffee may not be good for you if you have certain health problems.

There are many coffee drinkers around the world (author included). It is estimated that drinking coffee is a ritual shared by about 80% of adults worldwide. So let’s try to pay some more attention to what most of us put daily into our body.

To make coffee, we brew ground coffee beans, which are the processed and roasted seeds of a coffee cherry plant. Coffee beans contain caffeine, tannin, fixed oil, carbohydrates, and more than 100 chemicals. Coffee is very low in calories if drank plain — no sugar, no heavy cream. It may be surprising to find out that coffee contains vitamins, nutrients, and minerals. It has vitamin B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), magnesium, potassium, phosphorus, manganese, folate, choline, sodium, and antioxidants such as polyphenols and hydrocinnamic acid.

Antioxidants are known for reducing inflammation and protecting against diseases. Coffee also contains about 200 mg of protein per 6 oz. cup. The protein intake can be increased by adding milk. It needs to be noted that the vitamin and mineral content varies depending on the variety of the coffee plants, the region of growth, and the processing and roasting methods.

Health benefits of coffee

Coffee is a psychostimulant. Research indicates that it helps increase alertness and may also improve mood and limit depression. It may also help with simple and complex attention and with working memory. (Generally speaking, working memory is the ability to perform mental operations on immediate memory (Lin, Y.S. at al. 2023).) Lifelong caffeine consumption may prevent cognitive decline and reduce risk of stroke and brain degenerative diseases such as Parkinson’s and Alzheimer’s.

According to Donald Hensrud of the Mayo Clinic (2022), coffee can be somewhat protective in Parkinson’s disease, type 2 Diabetes, liver disease, heart attack and stroke. Decreased risk for Parkinson’s among coffee and tea drinkers was found in a 2013 study (Qi, H. & Li, S.). Drinking coffee also reduces the risk of cardiovascular diseases (Muchira, J. 2022). Coffee is low in calories so it may help with weight management, providing that you do not put a lot of sugar and heavy cream in it.

How many cups per day are beneficial?

There is not much consensus in this area. Some research suggests that drinking caffeine in moderate amounts is safe up to 400 mg, which is about 4 cups of coffee daily (Wilson, C. 2018). However, intake of several grams can cause toxicity and potential lethality in arrhythmias and myocardial infarctions. Some other research indicates that caffeine may not be harmful in up to about 5 cups per day.

However, other research suggests that only 1-to-2 cups of coffee daily is beneficial and drinking more than 6 cups per day was associated with 53% higher probability of dementia (Pham, K. at al. 2022). Drinking 2-to-3 cups of coffee was associated with the lowest risk for heart arrhythmias, but 4-to-5 cups was best for warding off atrial fibrillation (Muchira, J. 2022), and drinking about 3 cups per day offered maximum protection from developing Parkinson’s disease (Qi, H. & Li, S. 2013).

Side effects of coffee

In sensitive people, the caffeine in coffee may interfere with sleep and raise anxiety. On average, caffeine remains in the body for about 5 hours, so it is better to stop drinking it after 2 or 3 PM. However, this depends on your body mass and degree of tolerance. Some people can drink it after supper and still have a good night’s sleep. If you drink a lot of coffee, you may experience withdrawal. Coffee can interfere with pain medications and can cause headaches and migraines. It may hinder absorption of iron, calcium and zinc. Excessive drinking of coffee is also linked to kidney stones. All research also points to recommendations that pregnant and breast-feeding women should limit caffeine intake and they need to talk to their doctor about it.

About the Author

Barbara Koltuska-Haskin, Ph.D., is a neuropsychologist in private practice in Albuquerque, New Mexico with over 30 years of clinical experience, and the author of How My Brain Works: A Guide to Understanding It Better and Keeping It Healthy. Her book has won 2 International Book Awards and 5 National Book Awards.