Selenium deficiency in the British diet could be corrected with new fertiliser
Wednesday 9 September 2009
British diets contain only around half the selenium we need. New research shows how our dietary intake could easily be brought up to recommended levels by adding selenium to the fertilisers applied to British wheat.
The world food crisis is not just about providing enough food; it's also about people getting the right food. Micronutrients such as selenium (Se) are only needed in small amounts but are still essential to health. British diets are low in Se. “The average UK diet contains about half the daily reference nutrient intake”, explains Professor Margaret Rayman of the University of Surrey.” Low Se levels in the diet have been linked to: increased risk of death, poor immune function, male infertility, female reproductive problems and decreased brain function in the elderly. It has also been suggested that low Se increases the risk from cancer. Part of the problem is the low levels of Se in UK wheat (around 20 times less than those in US wheat). Consequently we are getting less Se than we should when eating bread, cakes and biscuits baked with British flour.
Research findings, released for the first time today at the British Science Festival show that adding tiny amounts of Se to the soil (around 20 g per ha) brings Se levels in British wheat grain up to those found in their US counterparts. These higher levels were reflected in products baked with flour milled from the grain. A slice of bread baked from a Se fertilised crop had around 13 times the Se content of bread baked from the control crop (10 ug of Se per slice compared to 0.76 ug in the control). Just three of four slices of bread with improved Se levels would make up the deficit between the present average intake and the recommended levels for females and males. Little of the added Se was detected in the soil after crop harvest and none was found in the subsequent wheat crop. This demonstrates that a build up of Se in the soil is unlikely, minimising the risk of environmental problems.
Professor Steve McGrath of Rothamsted Research states “This is a really easy and cheap solution to a public health problem. The government should be pushing the industry to fortify fertilisers in this way.”