'No evidence' that coffee drinking harms heart

Long-term heavy coffee drinking does not increase the risk of coronary heart disease (CHD) say Harvard researchers, results that also have positive implications for the stimulant drink industry.

Coffee, one of the world's largest traded commodities produced in more than 60 countries and generating more than $70bn in retail sales a year, continues to spawn research and interest, and has been linked to reduced risks of certain diseases, especially of the liver and diabetes.

Studies have also continued into the possible role of coffee and/or caffeine and the risk of increased blood pressure, and heart disease. Indeed, Greek researchers recently proposed that caffeine increased aortic stiffness and, subsequently, the risk of heart disease (American Journal of Clinical Nutrition, 2005, Vol. 81, pp. 1307-1312).

The new prospective cohort study, published on-line in the journal Circulation (doi:10.1161/ circulationaha.105.598664), reports that both coffee and caffeine consumption may not be linked to an increased risk of coronary heart disease (CHD), conditions are the cause of 20 per cent of deaths in the US and 17 per cent of deaths in Europe.

The researchers used data from the 44,005 men of the Health Professionals Follow-up study, started in 1986, and the 84,488 women in the Nurses' Health Study, started in 1976, to investigate the link between coffee consumption and the risk of CHD.

Coffee consumption was measured from validated questionnaires that were administered every two to four years.

After approximately 20 years of follow-up there were 4427 recorded cases of coronary heart disease. After adjusting the results for age, smoking, alcohol consumption, and BMI, the researchers found that people who drank between four and five cups of coffee per day had the same risk of CHD as those who drank less one cup of coffee per month.

The average American consumption is 3.2 cups of coffee per day.

Women who drank more than six cups per day actually had a 28 per cent lower risk of CHD, while the same intake was associated with a 13 per cent lower risk.

The difference between the highest and lowest intakes of caffeine was also not significant.

"These data do not provide any evidence that coffee consumption increase the risk of CHD," concluded lead researcher Esther Lopez-Garcia from the Harvard School of Public Health.

However, the researchers did find that people who drank more coffee were more likely to be smokers, drink more alcohol, drink less tea, take vitamin supplements, or exercise regularly, all of which have been linked to increased risks of heart problems.

Based on this, it appears that it may be the other lifestyle factors of heavy coffee drinkers that may promote the risk of heart-related health problems.

This news is not only good for the coffee industry, but also for the caffeine-enriched products in the energy and stimulant drinks market.

Consumption leaped by 18 per cent in 2004 to 2,410m litres, and is expected to grow to over 4,100m litres in 2009, according to a 2005 Global Energy Drinks report from specialist drinks consultancy Zenith International.

Coca-Cola recently launched a mid-calorie cola containing coffee in France called Blak. The product is said to contain twice the caffeine of regular coke, a third less than the average cup of coffee and well below what is normally in energy drinks.