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World Action on Salt. Sugar & Health

Emphasized warning reduces salt intake: a randomized controlled trial


A new study by researchers in Croatia and Bosnia found that applying warning stickers on all household salt containers, similar to warning signs found on cigarette packets, significantly reduced salt intake and blood pressure (BP) in adults treated for hypertension. The randomised controlled trial split 150 participants into 2 groups: the control group (n=74) who received a leaflet about the harmful effects of salt and the intervention group (n=76) who in addition, received warning stickers. 

Salt intake was measured by 24-hr urinary sodium excretion (Na24) at the start of the trial and 1 and 2 months later. The average starting Na24 was 207 ± 71 mmol in the control group and 211 ±  85 mmol in the intervention group (P = .745). One month and 2 months later, a significant decrease was observed in the intervention group (to 183 ±  63 mmol and 176 ±  55 mmol; P < .0001), as opposed to the control group (203 ±  60 mmol and 200 ± 58 mmol; P = .1466).

As the majority of salt in less developed countries is added during cooking or at the table, an important strategy to reduce population salt intake would be to encourage the general public to reduce the amount of salt used at home. This study has demonstrated that applying health warning stickers could be part of such a strategy

The authors (Markota NP et al) concluded that “A short-term intervention cannot completely correct dietary habits, but in the long run, combined with other measures, it may significantly contribute to a reduction in salt intake and BP lowering, particularly in countries where industrial, processed food is not the main source of sodium.”

Steph Tucker, Assistant Nutritionist at WASH says “In transitional and developing countries, where the majority of salt is added at home, either as table salt, stock cubes or soy sauce, this is such a simple measure to replicate. By reinforcing the message that eating too much salt is bad for us at the point of us reaching for the salt container, this study shows that salt intake can effectively be reduced in the short term.”

For the full paper, click here [PDF 511KB].



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