--Gall stone disease

--Gout

--Depression

--Parkinson's disease

--Alzheimer's disease

How much is enough

The BMJ study found that three to five cups a day was the range associated with positive health outcomes. This corresponds to the 2015-2020 Dietary Guidelines for Americans definition of moderate coffee consumption as part of a healthy eating pattern.

The java jolt

By and large, moderate coffee intake is safe for healthy people, however some might need to limit intake. In The BMJ paper, high consumption of caffeinated (> 400 mg, about four cups) coffee was linked with a higher risk of fracture in women, but a lower risk in men. To that end, women at higher risk of fracture should probably limit caffeinated coffee to four cups a day. Pregnant women are advised to limit caffeine intake to 200 mg a day (about two cups), as higher amounts have been tied to risk of miscarriage, low birth-weight babies, and premature birth.

Some evidence shows that those with heart disease ought to limit caffeinated coffee to five cups a day to decrease risk of heart attack. Excess caffeine itself can cause one to feel jittery, agitated, and nauseous. Such adverse effects are more commonly experienced in persons who don't consume caffeinated beverages consistently. Caffeine also can interfere with sleep if consumed late in the day.

(Environmental Nutrition is the award-winning independent newsletter written by nutrition experts dedicated to providing readers up-to-date, accurate information about health and nutrition in clear, concise English. For more information, visit www.environmentalnutrition.com.)