The HMRC and Treasury consultation proposes reducing the Soft Drinks Industry Levy (SDIL) threshold from 5g to 4g per 100ml.

The consultation also proposes removing the exemption for milk-based drinks while introducing a ‘lactose allowance' to account for the natural sugars in the milk component of these drinks.

It also proposes removing the exemption for milk substitute drinks with ‘added sugars' beyond those sugars derived from the principal ingredient, such as oats or rice.

Dr Charlotte Eckhardt, the Dean of the Faculty of Dental Surgery at RCS England, said: ‘We fully support proposals to strengthen the SDIL by lowering the sugar threshold from 5g to 4g per 100ml and by expanding its scope to include sugary milk-based drinks, a raft of which have more sugar per 100ml than the worst offending fizzy drinks. These steps are essential for protecting children's dental health and encouraging healthier reformulations.'

RCS England called for a portion of the £338m SDIL revenue to be committed to prevention measures such as supervised toothbrushing programmes and community fluoride varnish schemes and for timely access to NHS dental services and general anaesthetic services to manage those suffering.

Dr Eckhardt added: ‘People need to understand the long-term health risks of excessive sugar consumption. This is a critical moment to drive meaningful change and prevent the preventable.'

The average sugar content of soft drinks fell by 47% between 2015 and 2024 after the sugar tax was announced. 

Research suggests sugar reductions delivered by the levy could have prevented up to 5,000 cases of obesity in girls in the last year of primary school while the incidence of hospital admissions for caries related tooth extractions for children aged up to 9 years has also declined.

A decision on the SDIL is expected in the Autumn Budget.