Tuesday March 11 2014
Bread and cereals were among the main sources of dietary salt
“Children eat too much salt,” reports The Daily Telegraph, one of several news outlets to report on new findings that have led researchers to call for further reductions in the salt content of processed food.
The news is based on the results of a study assessing the salt intake of 340 children in south London by keeping a record of everything they ate and drank over 24 hours and measuring the salt content in their urine.
It found that on average, children aged from five to six ate 3.75g salt/day, children aged from eight to nine ate 4.72g/day and 13 to 17 year olds ate 7.55g/day.
Bread, breakfast cereals and other cereal-based products were the biggest source of dietary salt (36%) followed by meat products (19%), milk and milk products (11%).
On average, five and six-year-old children in the study consumed 3.75g of salt a day – more than the Government’s recommended 3g maximum for that age group. Eight and nine-year olds consumed 4.72g a day – within their 5g limit. Thirteen to 17-year-olds consumed 7.55g a day – more than the 6g limit.
This study provides a single snapshot of the salt levels of a relatively small sample of children from south London only. It doesn’t tell us whether the same results would consistently be obtained if salt levels were measured on a number of different occasions in these children; or in a sample of children from another area. They also cannot tell us whether there are any detrimental health effects of this level of salt consumption.
Where did the story come from?
The study was carried out by researchers from St George’s University of London and Queen Mary University of London and was funded by the British Heart Foundation. It was published in the peer-reviewed medical journal Hypertension.
What kind of research was this?
This was a cross sectional study assessing dietary salt intake by measuring levels of salt in urine among five to six years olds, eight to nine years olds and 13 to 17 year olds in south London, identifying the main sources of salt in children’s diets.
Cross-sectional studies are the ideal study design to assess current salt intake; however, they only provide a single snapshot. They don’t tell us whether the same results would consistently be obtained if salt levels were measured on a number of different occasions. They also cannot tell us whether there are any detrimental health effects of this salt consumption.
What did the research involve?
Dietary salt intake was assessed in 340 children by analysing the level of sodium in urine collected over 24 hours.
The Scientific Advisory Committee on Nutrition (SACN) recommends a maximum intake of salt of 6g a day for adults.
Although there are existing recommendations for salt intake for children, researchers devised their own daily upper limits based on body size:
- 2g for three to four year old children
- 3g for five to eight year old children
- 4g for nine to 11 year old children
- 5g for 12-15 year old children
- 6g for young adults aged 16 years and over
The children’s dietary salt intake was compared to the study’s own maximum salt intake recommendations.
To identify the sources of salt in their diet, children were also provided with a digital camera and asked to photograph everything they ate over 24 hours. The parent or child was also asked to keep a detailed dietary record of the food and drinks consumed. Details of recipes used were requested, as well as brand names of products, cooking methods, and portion sizes using household measurers.
What were the basic results?
The average salt intakes were:
- 3.75g/day for five to six year olds
- 4.72g/day for eight to nine year olds
- 7.55g/day for 13 to 17 year olds.
Compared to the study’s own maximum daily intake recommendations:
- 66% of five to six year old children ate too much salt
- 73% of eight to nine year olds ate too much salt
- 73% of 13 to 17 year olds ate too much salt
The main sources of dietary salt were cereal-based products, such as bread, breakfast cereals, biscuits, cakes, pasta and rice (36%), meat products, including chicken, turkey, sausages and ham (19%), milk and milk products, such as cheese (11%).
How did the researchers interpret the results?
The researchers concluded “this study demonstrates that salt intake in children in south London is high, with most of the salt coming from processed foods. Much further effort is required to reduce the salt content of manufactured foods.”
This study has found that salt intake in 340 children in south London is high. The researchers have proposed new maximum recommendations for salt intake based on recommendations for adults adjusted for differences in body size. Based on the study's own recommendations on salt intake, around two-thirds of five to six year olds, and three-quarters of those aged eight to nine and 13 to 17 had too much salt in their diet.
The scope of the study has some limitations. It provides a single snapshot of the salt levels of a relatively small sample of children from south London. It doesn’t tell us whether the same results would consistently be obtained if salt levels were measured on a number of different occasions in these children; or in a sample of children from another area. They also cannot tell us whether there are any detrimental health effects of this level of salt consumption.
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.