Image copyright PA

A sugar tax may have to be introduced to curb obesity rates, the chief medical officer for England has said.

Dame Sally Davies told a committee of MPs that unless the government was strong with food and drink manufacturers, it was unlikely they would reformulate their products.

She said she believed "research will find sugar is addictive", and that "we may need to introduce a sugar tax".

The food industry said it was working on reducing sugar in products.

Speaking to the health select committee, Dame Sally said: "We have a generation of children who, because they're overweight and their lack of activity, may well not live as long as my generation.

"They will be the first generation that live less, and that is of great concern."

Education urged

She said being overweight had been "normalised", adding: "I worry that we have re-sized a women's dress size so that a size 14 now was a size 12 when I was student.

"We have to find a new way - not of ostracising people who are obese and making them feel bad about themselves - but somehow of helping them to understand this is pathological and will cause them harm."

She said she thought researchers would find that sugars were addictive, and the public needed to have "a big education" over how "calorie packed" some smoothies, fruit juices and carbonated drinks were.

Media playback is unsupported on your device Media caption In November, the president of Coca-cola Europe was challenged on Newsnight about the amount of sugar in its drinks

She said: "People need to know one's fine, but not lots of them.

"We may need to move towards some form of sugar tax, but I hope we don't have to."

Earlier this year, doctors called for a soft drinks tax to reduce sugar intake.

Image caption Milkshakes, cola drinks, some brands of fruit-flavoured water, energy drinks and fruit juices contain more sugar than many people think

'Voluntary pledges'

The charity Sustain, which advises the government on the food and farming industry, says the UK consumes more than 5,727 million litres of sugary soft drinks a year. Adding a 20p tax for every litre sold would raise more than £1.1bn.

The Department of Health already has a "responsibility deal", which is a series of voluntary pledges by industry designed to tackle issues such as obesity.

Facts about sugar Evidence shows most adults and children in the UK eat more sugar than is recommended as part of a healthy balanced diet

Food and drinks that have a lot of added sugar contain calories, but often have few other nutrients

Sugary foods and drinks can also cause tooth decay, especially eaten between meals

Sugar found naturally in whole fruit is less likely to cause tooth decay than juices or blends because the sugar is contained within the body of the fruit

Source: NHS Choices Five foods surprisingly high in sugar

Much of the focus of those pledges is on reducing salt and calorie count rather than sugar per se.

And ministers are also pushing ahead with front-of-pack labelling, which includes information about sugar, but again, this will be voluntary.

Front-and-back labelling will include a combination of colour coding and nutritional information that will be used to show how much fat, salt and sugar and how many calories are in each product.

A Department of Health spokesperson said: "To help the nation to be healthier by eating fewer calories, including sugar, we are working with industry through the Responsibility Deal.

"This work has already delivered results but we have always been clear that, if food and drink companies fail to act, we will look at other options and are keeping all international evidence under review."

Terry Jones, of the Food and Drink Federation, said any extra tax on sugar would "hit the poorest families hardest at a time when they can least afford it."

Sugar content was already clearly labelled among products' ingredients, Mr Jones said.

He said: "Food and drink producers in the UK have taken action to reduce salt and saturated fat in the diet, in line with robust evidence linking excessive consumption of these nutrients with a negative impact on health."

Prof Barry Everitt, Professor of Behavioural Neuroscience, University of Cambridge, said pinning down whether sugar was actually addictive was a complex matter.

He said sugar - and fats - did impact on the chemistry of the brain's reward circuits - but in a much smaller way than drugs such as cocaine.

He said: "The important issue is that some individuals lose control over their food, especially sugar (and junk or fat-rich) food. This small sub-group might, then be viewed as 'addicted', but it may also be discovered that the loss of control in this sub-group might have a predisposing condition.

"The message that 'we'd better watch out for this sugar stuff is misleading', as far as I am concerned, because it suggests if you eat it you risk becoming addicted and the evidence does not support that."