At least one-third of children under the age of five - that is 200 million children worldwide - are either undernourished or overweight, a major new report from UNICEF has revealed.

According to the findings, almost two-thirds of children aged between six months and two years are not being fed food that supports their rapidly growing bodies and brains.

These children are therefore at risk of poor brain development, learning difficulties, reduced immunity, increased infections and in some cases, death.

"Despite all the technological, cultural and social advances of the last few decades, we have lost sight of this most basic fact - if children eat poorly, they live poorly," explained UNICEF executive director, Henrietta Fore,

She noted that millions of children subsist on an unhealthy diet "because they simply do not have a better choice".

"The way we understand and respond to malnutrition needs to change. It is not just about getting children enough to eat, it is above all about getting them the right food to eat. That is our common challenge today," she insisted.

The report states that poor feeding and eating practices begin in the earliest days of a child's life. For example, despite all the known benefits associated with it, just 42% of children under six months of age are exclusively breastfed.

It notes that the sale of formula milk has increased in many upper middle-income countries, such as Turkey and China, largely due to the inappropriate marketing of these products and inadequate policies aimed at promoting and supporting breastfeeding.

The report also notes that when children start to be weaned onto solid foods at around six months of age, too many are introduced to the wrong kind of diet. For example, almost 45% of children worldwide who are aged between six months and two years, are not fed any fruit or vegetables, while almost 60% do not eat any eggs, dairy, fish or meat.

According to the report, children face a "triple burden of malnutrition":
-Undernutrition
-Hidden hunger caused by a lack of essential nutrients
-Overweight.

Currently, around 149 million children under the age of five have stunted growth or are too short for their age, 50 million are wasted or too thin for their height and 40 million are overweight or obese.

A further 340 million - that is 50% of all under-5s - are deficient in essential vitamins and nutrients, such as iron and vitamin A.

The report points out that as children get older, their exposure to unhealthy food "becomes alarming". This is largely due to inappropriate marketing and advertising, increasing access to fast food and sugar sweetened drinks, and the easy availability of ultra-processed foods.

For example, in high-income countries, 62% of school-going teenagers consume sugary drinks at least once a day, while 49% consume fast food at least once a week.

As a result, overweight and obesity levels in childhood and adolescence are increasing throughout the world. Between 2000 and 2016, the proportion of overweight children between five and 19 years of age doubled from one in 10 to almost one in five.

Compared to 1975, 10 times more girls and 12 times more boys in this age group suffer from obesity today.

The report emphasises that the greatest burden of malnutrition is faced by children and teenagers in the poorest and most marginalised communities.

Just one in five children aged between six months and two years from the poorest households eats a sufficiently diverse diet for healthy growth. Even in high-income countries, the prevalence of overweight is more than twice as high in the poorest areas compared to the wealthiest areas.

In response to this, UNICEF has issued an urgent appeal to governments, businesses, the private sector and parents to tackle this issue. It makes a number of suggestions, including:
-Improving education and legislation around nutrition so that people are empowered to demand nutritious food
-Encouraging food suppliers to do the right thing by incentivising the provision of healthy, affordable foods
-Placing stronger controls on the marketing of unhealthy foods

"We are losing ground in the fight for healthy diets. This is not a battle we can win on our own. We need governments, the private sector and civil society to prioritise child nutrition and work together to address the causes of unhealthy eating in all its forms," Ms Fore said.

The report, State of the World's Children 2019: Children, Food and Nutrition: Growing Well in a Changing World, can be viewed here.