Salt fortified with both iodine and iron may help to improve iron status in populations where fortification of other staple foods does not achieve the desired coverage, according to a new study.
The research, which reviewed previous trials of double fortified salt and performed a cost:benefit analysis of a fortification programme found that the double fortification of salt, with both iodine and iron, “is a very attractive alternative where fortification of other staples is not currently possible.”
Writing in the journal Food Policy, the authors from Wilfrid Laurier University, Canada, and the Micronutrient Initiative added that double-fortified salt is helpful where cases anaemia is high and fortification of cereals is not easy.
“Practically everyone uses salt, making it the most natural vehicle for fortification.
The iodization of salt worldwide has been a remarkable public health success story,” said the researchers, led by Sue Horton from Wilfrid Laurier.
“Double-fortified salt is not the complete solution, but can be a component of the solution,” they added.
However, Clare Farrand, Nutritionist and World Action on Salt and Health (WASH) Coordinator, told FoodNavigator that with many countries around the world working to reduce population level salt intake, “salt should not now be promoted to the public as a means to increase iron and iodine intake.”
“Salt puts up our blood pressure, which is a major cause of cardiovascular disease, the leading cause of death worldwide. Using salt as a vehicle for fortification for iron, or iodine, presents a real conflict of interest in public health and it is the view of WASH that further research is needed to identify other possible vehicles for fortification,” she said.
The authors noted that iron deficiency is one of the most widespread micronutrient deficiencies worldwide.
It is associated with important health consequences, including reduced cognitive development in young children, lower economic productivity, in addition to higher maternal mortality and higher mortality in very young infants.
Horton and her colleagues noted that iron supplementation is not suitable in the long-term, whilst cereal fortification is not feasible in many countries where milling occurs locally.
“Iron fortification was ranked as the third-highest current development priority, out of more than forty interventions considered, at the 2008 Copenhagen Consensus,” noted the authors.
“Despite global goals to reduce iron deficiency anaemia, programs attempting to achieve these goals over the last 30 years have been dismally unsuccessful,” they added.
For many programmes, the researchers noted “it is clear that the root cause of failure is their inability to reach vulnerable populations with appropriate, sustainable and cost-effective solutions.”
Horton and her co-workers said that though there are several choices of fortified foods to enhance the micronutrient content, especially iron content, of diets in developing countries, it has been a challenge to reach the populations in the poor and remote locations where centrally processed foods are not commonly consumed.
“In these circumstances, double-fortified salt (fortified with an iron compound as well as iodine) has been proposed as a feasible and cost-effective alternative,” they noted.
The researchers undertook a literature survey to find the effect of double-fortified salt on hemoglobin, and then used previous research to make calculations for the cost:benefits applied to the Indian population.
When assessing previous research, they found that in six out of seven trials using double-fortified salt, anemia was improved.
Horton and her team recommended that double-fortified salt “is somewhat less attractive than wheat fortification, but a good choice where wheat is not a major staple.”
They added that level of fortification with both iodine and iron can be adjusted to take account of actual salt intake in the diet, so that fortification does not conflict with efforts to prevent excessive intake.
“We recognize that a certain amount of salt intake is essential for health, although excessive salt intake has undesirable health consequences such as higher blood pressure,” they said.
“If double fortified salt, with iron and iodine is the only means to successfully combat iron deficiency in some countries, they must be added all sources of salt in a quantity that allows salt intake to be gradually reduced to less than the WHO recommended maximum salt intake of 5g per day,” said Farrand
Source: Food Policy
Published online ahead of print, doi: doi:10.1016/j.foodpol.2011.06.002
“Double-fortified salt reduces anemia, benefit:cost ratio is modestly favourable”
Authors: S. Horton, A. Wesley, M.G. Venkatesh Manna