The average 4 year old ate 4.7g a day, which is considerably above the 2-3g recommended for this age group, the Journal of Human Hypertension reports. Each extra gram eaten raised blood pressure significantly, increasing the risk of heart disease and stroke.
In the study, which involved 2,127 4-18 year olds in Britain as part of an official audit for the Department of Health called the National Diet and Nutrition Survey, salt intake did not include salt added in cooking or at the table, although this often occurred.
About 1,658 kept a diary of what they ate and drank and their salt intake and blood pressure was recorded.
The children eating the highest salt diet had the highest levels of blood pressure, even after other factors such as age, sex and weight had been taken into account.
Jo Butten of Consensus Action on Salt and Health said: “The message for parents is to check labels, especially on foods such as breakfast cereals and snack products, which they may not expect to contain high levels of salt, and choose the lower salt options.
“It may be difficult for parents to tell their children they can’t have crisps every day, or that they need to eat a different breakfast cereal, or that some instant noodles should be avoided completely, but surely it’s a small price to pay to reduce their risk of having a heart attack or stroke when they are older?”