Image copyright Christopher Furlong Image caption High Streets in the north of England and the Midlands were more likely to have a higher concentration of 'unhealthy' businesses, the study suggested

A league table of the "unhealthiest High Streets" has named Preston as the UK's worst offender.

The Royal Society for Public Health assessed 70 areas in the UK according to the types of businesses found there.

Bookmakers, loan shops, tanning salons and fast-food outlets were viewed as having a "negative impact" on public health, while leisure centres and health services were deemed positive.

Shrewsbury, in Shropshire, was named as having the "healthiest" High Street.

The society has called for a limit of 5% of each "unhealthy" type of business on a High Street to avoid saturation.

Image copyright Getty Images Image caption Loan shops were considered as having a negative impact on public health

Britain's "unhealthiest High Streets" ranked

1. Preston

2. Middlesbrough

3. Coventry

4. Blackpool

5. Northampton

6. Wolverhampton

7. Grimsby

8. Huddersfield

9. Stoke-on-Trent

10. Eastbourne

Source: Royal Society for Public Health

Businesses were scored by more than 2,000 members of the public, and by public health and local government experts, on the extent to which they encouraged healthy choices, promoted social interaction, provided access to health advice and promoted positive mental wellbeing.

The league table was drawn up based on scores and the prevalence of each type of businesses in each High Street.

The research found that towns and cities in the north of England and the Midlands were more likely to have higher concentrations of businesses which were deemed potentially harmful to the public's health.

Image caption Independent cafes were seen as a healthy business for the High Street

Britain's "healthiest High Streets" ranked

1. Shrewsbury

2. Ayr

3. Salisbury

4. Perth

5. Hereford

6. Carlisle

7. Cambridge

8. Cheltenham

9. York

10. Bristol

Source: Royal Society for Public Health

The organisation's chief executive Shirley Cramer said the table was by no means a reflection on whether each area was generally healthy or unhealthy, but it highlighted some trends.

"Our research does find higher concentrations of unhealthy businesses exist in places which already experience high levels of deprivation and premature mortality," she said.

She said local authorities should be given more planning powers to limit the numbers of certain types of businesses on High Streets.

The society is also campaigning for public health criteria to be a condition of licensing for all types of business.

It also wants mandatory food hygiene ratings linked to calorie and nutrition labelling for fast food outlets and for councils to be able to set varying business rates to encourage healthier outlets.

A government spokesman said planning measures had been introduced to stop High Streets becoming a "sea of payday loan and betting shops" and made it much easier for shops to change to "positive other uses" like cafes and health clubs.

But Peter Craske from the Association of British Bookmakers said betting shops had long been adding value to High Streets.

"We've been trading on the High Street for fifty years, and we employ 40,000 people and serve over eight million customers," he said.

"The majority of our shops have been in the same location for over 20 years and as with any other retailer we open because there are customers for our products."