Researchers from the University of Leeds and University of Surrey examined the ingredients of 921 of the most popular yoghurts sold in supermarkets.
They found fewer than one in 10 of all products (9%) and only 2% of children’s yoghurts were classed as low in sugar, and contained the level required to carry a green “traffic light” nutritional label which is considered a healthy choice.
For a food product to be classed as low sugar it cannot contain more than 5g per 100g.
Children’s yoghurts typically contained 10.8g per 100g, the equivalent of more than two sugar cubes, the study found.
Organic yoghurts typically had 13.1g of sugar per 100g, while natural or Greek varieties had the lowest at around 5g.
Researchers separated the products and their findings into eight categories:
:: Desserts – 16.4g per 100g
:: Organic – 13.1g per 100g
:: Flavoured – 12g per 100g
:: Fruit – 11.9g per 100g
:: Children’s – 10.8g per 100g
:: Dairy alternatives – 9.2g per 100g
:: Drinks – 9.1g per 100g
:: Natural and Greek – 5g per 100g
“We conclude not all yoghurts are as healthy as perhaps consumers perceive them and reformulation for the reduction of free sugars is warranted,” the team said.
They warned the “health halo” effect means consumers often underestimate the nutritional content of organic products.
Lead author Dr Bernadette Moore, from the University of Leeds, said: “While there is good evidence that yoghurt can be beneficial to health, products on the market vary widely in nutrient content.
“Items labelled organic are often thought of as the ‘healthiest’ option, but they may be an unrecognised source of added sugars in many people’s diet.”
The NHS recommends that children aged four to six have no more than 19g of sugar, or five sugar cubes a day, and it is advised that those aged seven to 10 years old consume less than 24g daily.
Dr Barbara Fielding, study co-author from the University of Surrey, said: “In the UK, on average, children eat more yoghurt than adults, with children under three years old eating the most.
“It can be a great source of protein, calcium, and vitamin B12.
“However, we found that in many of the yoghurt products marketed towards children, a single serving could contain close to half of a child’s recommended daily maximum sugar intake.”
The study comes amid a government-drive to encourage manufacturers to reduce sugar content in their products – including yoghurts – by 20% by 2020.
A progress report published by Public Health England in May showed sugar content in yoghurts was reduced by 6% in the first year, making it the only food category to exceed the initial 5% target.