Reducing the Salt Added to Takeaway Food: Within-Subjects Comparison of Salt Delivered by Five and 17 Holed Salt Shakers in Controlled Conditions

Abstract

ObjectivesTo determine if the amount of salt delivered by standard salt shakers commonly used in English independent takeaways varies between those with five and 17 holes; and to determine if any differences are robust to variations in: the amount of salt in the shaker, the length of time spent shaking, and the person serving.DesignFour laboratory experiments comparing the amount of salt delivered by shakers. Independent variables considered were: type of shaker used (five or 17 holes), amount of salt in the shaker before shaking commences (shaker full, half full or nearly empty), time spent shaking (3s, 5s or 10s), and individual serving.SettingControlled, laboratory, conditions.ParticipantsA quota-based convenience sample of 10 participants (five women) aged 18–59 years.Main Outcome MeasuresAmount of salt delivered by salt shakers.ResultsAcross all trials, the 17 holed shaker delivered a mean (SD) of 7.86g (4.54) per trial, whilst the five holed shaker delivered 2.65g (1.22). The five holed shaker delivered a mean of 33.7% of the salt of the 17 holed shaker. There was a significant difference in salt delivered between the five and 17 holed salt shakers when time spent shaking, amount of salt in the shaker and participant were all kept constant (p<0.001). This difference was robust to variations in the starting weight of shakers, time spent shaking and participant shaking (ps</ = 0.001).ConclusionsFive holed salt shakers have the potential to reduce the salt content of takeaway food, and particularly food from Fish & Chip shops, where these shakers are particularly used. Further research will be required to determine the effects of this intervention on customers’ salt intake with takeaway food and on total dietary salt intake.

Nudging sugar portions: a real-world experiment

“…The present findings, that were derived from a real-world experiment, show that making minor changes to daily food environments can lead to positive effects on sugar intake in habitual behaviors. Modifying the functional design of sugar shakers resulted in a reduction of the amount of added sugar of 19.75% compared to the default condition, which strengthens the results on table salt use [ 7 – 10 , 15 ] and adds to the evidential basis that reducing dispensed quantities can sustainably change individual behaviors in public places.…”

The challenges of interventions to promote healthier food in independent takeaways in England: qualitative study of intervention deliverers’ views

“…Single-target interventions, with one nutritional focus, were rare. However, there was one widely cited example that involved replacing the 17-hole cap of a counter-top salt shaker with a 5-hole cap to reduce the amount of salt dispensed [ 32 , 33 ]. Multi-component interventions were more common, especially healthy catering award schemes.…”

“…Future work should look for opportunities to develop, deliver and evaluate covert (to the consumer) interventions. The 5-hole salt shaker is one such intervention, which we recently evaluated [ 32 , 33 ]. We concluded that their use is associated with lower relative sodium content of fish and chip meals [ 32 ].…”

Frequency of adding salt at the table and risk of incident cardiovascular disease and all-cause mortality: a prospective cohort study

“…Restricting the habit of adding salt to food at the table has been proposed to reduce salt intake [ 35 , 36 ]. Public health education or removing/replacing salt shakers could also partially reduce salt added at the table [ 4 , 37 , 38 ]. However, the habit of adding salt at the table is prevalent, whether in developed regions [ 3 – 5 ] or in low- and middle-income countries [ 12 , 39 – 41 ].…”