Doctors give wake-up call on dark side of caffeine

Sarah Whyte

Caffeine is creeping into our diets at an alarming rate with the number of cafes and energy drink sales ballooning in a decade, a consultation paper prepared for the Australian and New Zealand governments shows.

Australians drink 1 billion coffees a year while out and another 4 billion at home, according to the Australian Beverages Council.

The consumption of energy drinks has grown from 34.5 million litres in 2001 to 155.6 million litres in 2010.

Foods that contain a surprisingly high level of caffeine, including chocolate, muffins and breakfast cereals, are also on the rise, the paper said.

The burgeoning presence of caffeine in diets, particularly those of children, has led to a joint Australian and New Zealand health working group to review policy guidelines on the addition of caffeine in foods and drinks, to be released on Tuesday.

There are more than 40 products that can contain caffeine, yet don't necessarily have caffeine labelled in their ingredients list. When caffeine is ''naturally present'', such as in cocoa, the amount of caffeine is not listed, the report said.

Doctors are warning against excessive consumption of caffeine, which can lead to insomnia, nervousness, headaches, tachycardia, arrhythmia and nausea.

''Energy drinks have the potential to increase your heart rate and therefore blood pressure,'' said Rob Grenfell, director of cardiovascular health at the National Heart Foundation.

''It is unknown what the long-term effects of high dosages of caffeine are. However, increased blood pressure is a major risk factor for future coronary heart disease.''

But despite health warnings, there are no dietary guidelines on caffeine consumption. The Dietitians Association of Australia recommends against drinking more than four to five cups of instant coffee a day, or 300 to 400 milligrams per day.

V Pocket Rocket has 200 milligrams in just 100 millilitres.

Beyond coffees and energy drinks, there has been a growth in ''novelty'' products containing caffeine such as chewing gum and corn chips, the report said.