How much coffee is too much? Scientists decode

Drinking six or more cups of coffee a day can be harmful to your health, increasing the risk of heart disease by up to 22 per cent, a study claims.

A morning coffee is essential for many people looking to kick-start their day.

While the humble coffee may be a vital feature of the daily grind, researchers from the University of South Australia wondered how much caffeine is too much.

They investigated the association of long-term coffee consumption and cardiovascular disease, finding the point at which excess caffeine can cause high blood pressure, a precursor to heart disease.

According to the World Health Organization (WHO), cardiovascular disease is the leading cause of death, yet one of the most preventable.

This is the first time an upper limit has been placed on safe coffee consumption and cardiovascular health, according to the study published in The American Journal of Clinical Nutrition.

"Coffee is the most commonly consumed stimulant in the world -- it wakes us up, boosts our .