Wetenschap - 9 november 2011

Half as much salt, just as much appetite

People do not change what they eat at breakfast even when their bread has 52 percent less salt. They eat just as much bread without resorting to extra savoury fillings. This finding is useful when it comes to lowering salt intake in the Netherlands.

zoutbrood.jpg
zoutbrood.jpg

Foto: .

Wageningen researchers demonstrated this by giving students bread with decreasing salt content at breakfast. In one breakfast serving, the difference is about 0.65 grams. 'Frankly, I hadn't expected that such a big decrease would work,' says Dieuwerke Bolhuis, researcher in the Product Design and Quality Management Group. The research results appeared in early November on the website of the Journal of Nutrition.
During the experiment, 116 students breakfasted in the Restaurant of the Future for four weeks. They had a choice of bread, cornflakes, biscuit and a wide spread of sandwich fillings and fruit. 'The mornings were pretty much convivial mostly,' Bolhuis relates. 'There were also many cliques with people who know one another.' The breakfast-goers were divided into three groups, each of which got their food from separate counters. Unknown to them, they were given, respectively, normal bread, bread with less salt, and bread with less salt but more food flavouring.
In the last two groups, the salt content was lowered week by week. In the second week, it was 31 percent less than normal, and thereafter, 52 and 67 percent less. The researchers recorded how much the students ate and left behind. Even when salt was reduced by half, they consumed almost as much bread, without resorting to extra savoury sandwich fillings. The group of students given bread with extra food flavouring even ate as much when salt was reduced by 67 percent.
The results suggest that salt content in bread can be lowered. This is good news as the Dutch consume ten grams too much salt per day on the average. 'This gives rise to higher blood pressure,' says Bolhuis, 'and that in turn will lead to heart and cardiovascular diseases.' According to the Nutrition Centre, the maximum salt intake per day is six grams, while the World Health Organization places the limit at five grams.
After the experimental breakfast weeks, the researchers also conducted a taste test. It showed that the two diet groups rated less-salted bread better than the control group did. It seems that taste buds can adapt slightly. Differences vanish when something is spread on the bread. This may be why bread with so much less salt has been accepted. Breakfast-goers do not realize that their bread is less salted due to sandwich fillings. As such, Bolhuis does not think that halving the amount of salt will work with all products high in salt, such as prepared soups and sandwich meats.

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