Can of Coke a day increases heart attack risk by third

New sugar guidelines mean one can of fizzy drink would exceed the daily limit. Photo / iStock.

Just one can of fizzy drink a day can increase the risk of heart attack by a third and dramatically raise the chance of diabetes and stroke, the largest ever study has found.

The research by Harvard school of public health found that regularly drinking sugary drinks increases the risk of developing type 2 diabetes by a quarter (26 per cent), the risk of heart attack or fatal heart disease by a third (35 per cent) and the risk of stroke by a sixth (16 per cent).

The study - the most comprehensive review of evidence of health effects of sugary drinks to date - follows new official UK advice which says adults should restrict their sugar intake to just 30 grams (seven teaspoons) a day.

The guidelines mean that one can of fizzy drink such as Coke, would exceed the daily limit.

The new research looked at dozens of studies, and explored how different types of sugar metabolise in the body.

Experts said eliminating or cutting out sugar-sweetened drinks was a simple way to reduce weight and prevent a host of cardio-metabolic diseases.

Harvard Professor of Nutrition and Epidemiology Dr Frank Hu said: "Regular consumption of sugar-sweetened beverages can lead to weight gain because the liquid calories are not filling, and so people don't reduce their food intake at subsequent meals.

"Although reducing the consumption of sugar-sweetened beverages or added sugar alone is unlikely to solve the obesity epidemic entirely, limiting intake is one simple change that will have a measurable impact on weight control and prevention of cardio-metabolic diseases," Hu and his team conclude.

"Our findings underscore the urgent need for public health strategies that reduce the consumption of these drinks."

Hu said additional research was needed to explore the health effects of different types of sugars and how liquid versus solid forms of sugar affect the body.

The study was published in the Journal of the American College of Cardiology.

Public health experts said families should think carefully about whether children should be allowed fizzy drinks at all, and said people should be encouraged to swap such beverages for low calorie versions, or water.

Officials are now drawing up further advice about how to reduce sugar levels in the British diet. The plans could see reductions in standard portion sizes of chocolate and sweets.

Earlier this month, a study published in the Lancet found that Britain's junk food diet has become the leading cause of death and ill-health, ahead of smoking.

The study shows that 40 per cent of NHS resources are spent dealing with ills caused by potentially preventable lifestyle factors such as unhealthy eating habits, obesity, alcohol and smoking.

Dr Aseem Malhotra, cardiologist and adviser to campaign group Action on Sugar said: "The evidence is now overwhelming. Sugary drinks are linked to tens of thousands of deaths worldwide and eliminating them from the food supply would have a substantial impact in reducing hospital admissions within a very short space of time."