Possible health benefits of coffee include providing essential nutrients and supporting brain health. However, it can cause side effects such as anxiety and sleep problems.

The health effects of coffee are controversial. It contains a range of nutrients and may reduce the risk of certain conditions.

However, it also contains caffeine, a stimulant that can cause problems in some people and disrupt sleep.

This article takes a detailed look at coffee and its health effects, looking at both the positives and negatives.

Coffee is rich in many of the nutrients naturally found in coffee beans.

A typical 8-ounce (237-gram) cup of coffee provides a source of:

  • vitamin B2 (riboflavin)
  • vitamin B5 (pantothenic acid)
  • vitamin B1 (thiamine)
  • vitamin B3 (niacin)
  • folate
  • manganese
  • potassium
  • magnesium
  • phosphorus

The caffeine content of a single cup of coffee is somewhere around 95 mg.

Caffeine is a known stimulant. In your brain, it blocks the function of an inhibitory neurotransmitter (brain hormone) called adenosine.

By blocking adenosine, caffeine increases activity in your brain and releases other neurotransmitters like norepinephrine and dopamine. This reduces tiredness and makes you feel more alert.

A 2018 randomized controlled trial demonstrated that both caffeinated and decaf coffee can lead to a short-term boost in brain function, improving mood, reaction time, vigilance and general cognitive function.

Parkinson’s is the second most common neurodegenerative disease and is caused by the death of dopamine-generating neurons in the brain.

Coffee drinkers may have a lower risk of Parkinson’s disease.

More research is necessary to better understand this. Speak with your doctor for more information about ways to lower the risk of Parkinson’s disease.

Type 2 diabetes is characterized by elevated blood sugar levels due to resistance to the effects of insulin.

Studies show that coffee drinkers may have a reduced risk of developing type 2 diabetes. According to a 2021 review, drinking coffee often may lower type 2 diabetes risk by protecting the liver and preserving beta cell function.

A 2018 systematic review shows similar results, showing that coffee provides significant antioxidant and anti-inflammatory effects.

A 2021 review concluded that all types of coffee, including decaf, may protect against chronic liver disease.

Coffee drinkers may also have a significantly lower risk of liver cancer. More research is necessary.

In a 2018 study, people who drank at least 4 cups of coffee per day had a 63% lower risk of depression compared with those who drank under 1 cup per day.

A 2020 article also found that drinking coffee may help lower the risk of depression. However, the article also notes that more research is necessary.

While coffee can offer some health benefits, it can also cause side effects.

Consuming too much caffeine can lead to:

  • jitteriness
  • anxiety
  • heart palpitations
  • sleep problems

If you are sensitive to caffeine and tend to become overstimulated, you may want to avoid coffee altogether.

Caffeine can also have diuretic and blood pressure-raising effects. However, a 2023 systematic review showed that coffee drinkers experienced a lower risk of high blood pressure. This suggests that, over time, coffee may lower rather than raise blood pressure.

Some people — especially pregnant people — should definitely avoid or severely limit coffee consumption.

People with anxiety issues, high blood pressure, or insomnia might also want to reduce their intake for a while to see if it helps.

Addiction and withdrawal

Another issue with caffeine is that it can lead to addiction.

When people consume caffeine regularly, they become tolerant to it. It either stops working as it did, or a larger dose is needed to produce the same effects.

When people abstain from caffeine, they can experience withdrawal symptoms. These can include:

  • headaches
  • exhaustion
  • brain fog
  • irritability

These symptoms can last for a few days.

Speak with a doctor for information on how to manage symptoms of withdrawal if you wish to stop drinking coffee.

There are some things you can do to maximize the beneficial health effects of coffee.

The most important thing is to not add a lot of sugar to it.

Another technique is to brew coffee with a paper filter. Unfiltered coffee contains cafestol, a substance that can increase cholesterol levels.

Bear in mind that some coffee drinks at cafés and franchises contain hundreds of calories and a lot of sugar. It is best to drink these in moderation.

Given that the association is strong and consistent among studies, coffee may indeed play a positive role in your health. It provides various essential nutrients, and it may support brain health, protect against Parkinson’s disease, and lower the risk of type 2 diabetes.

However, coffee can provide some side effects, such as headaches, jitters, and disrupted sleep. Stopping drinking coffee can also cause withdrawal symptoms.

Speak with a doctor for more information about the possible health benefits of coffee.