The researchers based at Queen Mary University of London found that many other shakes contain more than half the daily recommended amount of calories for an adult.

They say that of the 46 products included in the survey with nutrition labelling available online, all would receive a red/high label for excessive levels of sugar per serving.

Action on Sugar, which is made up of specialists concerned with sugar and its effects on health, are calling for mandatory traffic light-coloured nutrition labelling across all menus.

Public Health England (PHE) also has a sugar reduction programme as part of the government’s childhood obesity plan. It is challenging businesses to cut sugar by 20% by 2020 and milkshakes are included in that.

Professor of Cardiovascular Medicine at Queen Mary University of London and Chairman of Action on Sugar Graham MacGregor said ‘Despite milkshakes being incorporated into the Public Health England’s Sugar Reduction Programme as part of the government’s childhood obesity plan, it is clear from our survey that much more needs to be done than a 20% reduction. These very high calorie drinks if consumed on a daily basis, would result in children becoming obese and suffer from tooth decay – that is not acceptable.

‘These high calorie milkshakes need to be reduced immediately below the 300kcal per serving.’

Dr Linda Greenwall and charity founder of the Dental Wellness Trust says, ‘These findings are remarkable, especially given tooth decay among children in Britain is now at a record high, largely because food and drink products are packed with unnecessary sugar.

‘As the number of youngsters admitted to hospital to have their teeth extracted continues to escalate at a cost of more than £36million to the NHS, manufacturers, the out of home sector and parents must take immediate responsibility by significantly reducing the amount of sugar given to children, as well as enforcing daily brushing to reduce the likelihood of tooth decay.’

For more information on Action for Sugar see www.actiononsugar.org