Sweet foods popular with children can also mask dangerous levels of salt, parents were warned yesterday.

Desserts, sweet drinks and snacks, which may on the face of it pose no harm in terms of salt content, can actually carry large amounts of the substance.

Consensus Action on Salt and Health (Cash) wants an overall reduction of salt in food manufacturing and clearer labelling on foods so that parents can make informed choices on what their children eat.

The call comes after tests of a range of food products raised concerns about hidden salt content. One small portion of Butterkist's The Simpsons honey nut popcorn contained 1.26g of salt.

That is 63% of the daily limit for children aged between one and three and 42% of the guideline amount for those aged between four and six.

However, since the tests were carried out, the manufacturers have taken the product off the market.

Half a packet of Tesco banana flavour Delight pudding made with skimmed milk carried 1g of salt, and tests on one blueberry muffin showed it contained the equivalent salt level of two packets of crisps.

Analysis of a quarter- portion of a Heinz treacle sponge pudding showed that it has 27% of the salt content limit for a child aged between four and six.

Ollie Heath is nine years old and has never had a McDonald's. His favourite snack is a few slices of mango.

His eating habits may be unusual among his friends, but his mother has brought up her children to understand the importance of fresh, wholesome food. Salt is not allowed for Ollie but Amanda Heath does like to add salt to her plate from time to time.

Mrs Heath, a photographer from Edinburgh, said: "I am very salt-conscious when it comes to Ollie and his sister, but having said that I do like salt myself, although I only use sea salt which is slightly less harmful.

"I never buy processed food. I just think it is absolute rubbish, full of salt and colourings, and at home we make everything from scratch so you know exactly what is in it.

"I am really passionate about food and cooking and about people eating well.

"I think people just need re-educating about the quality of food they eat and what it actually contains."

Pointing out that recent research showed children with high salt diets had higher blood pressure, Cash chairman Professor Graham MacGregor said: "We want to see all manufacturers doing everything they can to reduce the salt they put in children's food."

The daily recommended maximum salt intake for children depends on their age. It starts at 2g per day for children aged one to three years, rising to 3g daily for youngsters aged four to six years. Children aged seven to 10 years should eat no more than 5g per day, according to the Food Standards Agency.

A spokesman for Monkhill Confectionery, which makes Butterkist, said its ready-to-eat The Simpsons honey nut popcorn had been de-listed last autumn and was no longer being made.

A Heinz spokesman said: "Heinz has been praised for reducing salt in beans, soups, pasta and ketchup and our new Hidden Veg range has lower salt especially for kids.

"But when it comes to our tinned sponge pudding, Cash and the Food Standards Agency accept we would need to add lots more sugar if we took the salt out."

A spokesman for Tesco could not be contacted last night.

At Grassroots Cafe in Glasgow, where Mrs Heath and her son had breakfast yesterday, chef Robin Campbell keeps a watchful eye over the salt content of the food he serves up.

Mr Campbell, 32, said: "Everything we make here is made from scratch so it is easy to keep an eye on how much we use. Salt is really kept to a minimum. We use a lot of herbs and spices so the food is really tasty and full of flavour.

"It breaks my heart when you send out the food and the first thing a customer will do is sprinkle on the salt when they haven't even tasted it."