Coffee: good for your health or not?

This is general information, not medical advice. Always discuss your blood values with your doctor.

1. 1

   No sign of harm at usual amounts

   An umbrella review of 201 meta-analyses of observational studies and 17 meta-analyses of interventional studies (Poole et al., BMJ 2017) found that coffee was more often linked to benefit than to harm. The largest benefit was at 3 to 4 cups a day versus none: about 17% lower all-cause mortality, 19% lower cardiovascular mortality and 15% lower cardiovascular disease. These are observational associations, not proof of cause. The exceptions were pregnancy and women at high risk of fractures. The studies looked at coffee itself, not at sugar, syrup or cream.

2. 2

   Heart rhythm: no need to cut out coffee

   In the DECAF trial (Wong et al., JAMA 2025), 200 patients with persistent atrial fibrillation after a successful cardioversion were randomised to about one cup of regular coffee a day on average or to complete abstinence from coffee and caffeine. After 6 months the rhythm problem had returned in 47% of the coffee group versus 64% of the abstinence group (HR 0.61). The trial was open-label and ran for only 6 months, and just 69% of the abstinence group stuck to the ban throughout. So it does not support the old advice to cut coffee by default, but it is a single study in patients.

3. 3

   Cholesterol: choose filtered coffee

   Unfiltered coffee, such as French press, boiled coffee and Turkish or Greek coffee, contains cafestol and kahweol, substances that raise LDL cholesterol. A meta-analysis of 14 randomised trials (Jee et al., 2001) found a dose-dependent rise in total and LDL cholesterol with unfiltered coffee, and very little with filtered coffee. A later meta-analysis of RCTs (Cai et al., 2012) confirmed that coffee, especially unfiltered, raises total cholesterol, LDL and triglycerides, and that people with high blood fats are more sensitive.

4. 4

   How much is safe? Up to 400 mg a day

   EFSA (2015) considers a habitual intake of up to 400 mg of caffeine a day from all sources of no concern for adults who are not pregnant, and 200 mg a day for pregnant women. A cup of coffee contains roughly 80 to 110 mg, so 400 mg comes down to four or five cups. Caffeine from energy drinks and pre-workouts counts too. A single dose of 100 mg can delay falling asleep and shorten sleep in some adults.

Updated in October 2026