Latest data shows more than one in four children assessed were overweight or obese in 2016/17. With the gap in levels of obesity now 6.2 per cent between those living in the most disadvantaged areas (14.9 per cent) and the least disadvantaged (8.7 per cent).

The CMP is a national surveillance programme run by Public Health Wales recording the heights and weights of children in their reception year of primary school.

Linda Bailey, Consultant Lead for the Child Measurement Programme said: "The number of children that are obese at the age of four to five years old has been going in the wrong direction over the past two years.

"In particular, over the last two years the level of obesity has shown a statistically significant increase. While it is too soon to see an overall trend, there is an increasing gap in obesity levels between the most and least disadvantaged areas in Wales."

With the problem of obesity remaining prevalent in children and younger people, Public Health Wales created the Every Child Wales programme in July 2017.

The programme put together by both parents and health experts, aims to bring together a range of new and existing programmes to support parents in giving their child a happy and healthy start in life.

Every Child Wales was launched last year with the 10 Steps to a Healthy Weight to encourage parents to think about how they can be the best support for their child in their early years.

Over 2018, the programme aims to help parents of under-fives to recognise whether their child is of a healthy weight. Understanding the behaviours that contribute to obesity in the early years, with particular emphasis on reducing the consumption of sugary drinks, is important to future health.

Natalie Field, Consultant Lead for the 10 Steps to a Healthy Weight programme at Public Health Wales said: "Public Health Wales will be working with the Welsh Government to develop a new national Obesity Strategy. We expect to have a consultation version of this ready by July this year.

"The findings of the Child Measurement Programme underline just how much work we have to do to turn the tide on these figures. We are concerned that parents and professionals may find it difficult to recognise when children are overweight as it is more commonplace than it once was.

"Our research shows that parents are more likely to identify children who are a healthy weight as underweight. This may give them false reassurance that their overweight or obese child is okay. Our hope is through a variety of initiatives throughout the year we can go someway to change this perception."

Being overweight or obese can have a direct effect on children’s wellbeing – low self-esteem, anxiety and depression. Obesity can also lead to a range of other health problems in adulthood such a type II diabetes.

Every Child Wales will continue to provide parents and carers with easily accessible resources and practical advice to support the management of their child’s health and wellbeing.

Natalie Field continues: "If we get it right during the early stages of a child’s life we can build healthier and more resilient future population.

"Tackling childhood obesity not only prevents adverse health consequences, but prevention is so much easier than treatment for the child. We know that every parent wants the best for their children, and we want to give them all the tools and support to do just that," she concludes.