A junk food TV and online advertising ban comes into force.

Junk food adverts have been banned on television and online from Monday as part of a campaign to tackle childhood obesity.

Foods and drinks high in fat, salt, and sugar (HFSS) have been banned from being advertised on TV before 21:00 and online at any time, under a UK-wide ban.

This applies to products that are known to be the biggest drivers of childhood obesity, including soft drinks, chocolate and sweets, as well as pizza and ice cream.

Since October, the Food and Drink Federation (FDF) has voluntarily adhered to the new restrictions, demonstrating its commitment to promoting healthier eating habits.

In addition to more obviously unhealthy foods, the ban also includes some breakfast cereals and oatmeal, sweetened bread products, and main meals and sandwiches.

As well as more obviously unhealthy foods, the ban also includes some breakfast cereals and oatmeal, sweetened bread products, and main meals and sandwiches.

The decision about which products fall under the ban is based on a scoring tool that balances their nutrient levels with whether they are high in saturated fat, salt, or sugar.

Plain oats and most porridge, muesli, and granola are not banned by the action, but some versions with added sugar, chocolate, or syrup may be affected.

Companies can still promote healthier versions of banned products, which the government hopes will help food manufacturers develop healthier recipes.

Josh Tilly, brand strategy director at marketing agency Initials CX, said companies will still be allowed to advertise their brands in general, but not specific products.

Advertisements containing “things like the PepsiCo logo or McDonald’s arches” will not be banned, he said, meaning larger companies may be less affected by the new restrictions.

“Smaller companies can’t necessarily afford those big brand campaigns,” Tilly said. Their advertising is based on “educating people” about specific products, “and they won’t be able to do that anymore.”

The ban only includes ads that may feature unhealthy products being seen by viewers. Fast-food companies will still be able to advertise using their brand names.

Previously, the HFSS forbade food and beverage advertisements on any platform where more than 25% of the audience was under 16.

Companies that do not comply with the new rules risk action by the Advertising Standards Authority (ASA).

NHS data shows that almost one in 10 (9.2%) of reception-aged children are now living with obesity, while one in five have tooth decay by the age of five.

Obesity is estimated to cost the NHS more than £11 billion every year.

Evidence suggests that exposure to unhealthy food advertisements may affect what children eat from a young age, resulting in an increased risk of being overweight or obese.

The government estimates that the advertising ban would prevent approximately 20,000 cases of childhood obesity.

Katherine Brown, professor of behaviour change in health at the University of Hertfordshire, said the ban was “long overdue” and “a step in the right direction.”

He said, “Children are susceptible to aggressive marketing of unhealthy foods and exposure to them increases their risk of developing obesity and related chronic diseases.”

Ms. Brown called on the government to make nutritional options “more affordable, accessible, and attractive.”

According to the FDF, manufacturers are “committed to working in partnership with the government and others” to help people make healthier choices.

It said, “Investing in developing healthier products has been a key priority for food and drink manufacturers for many years, and as a result, our members’ products now contain one-third the salt and sugar and one-quarter the calories compared to ten years ago.”