News
Obese people may need more vitamin D
14 March 2012
Older adults with a higher body mass index have lower vitamin D levels, which needs to be taken into account when determining an adequate dietary vitamin D intake, a new UK study suggests.
25 July 2014
A new review from the UK says that due to a lack of dietary diversity, deficient intakes of iron, iodine and vitamin A are also widespread in industrialized nations.
The review identified recent reports on the worldwide incidence of micronutrient deficiencies (1). New studies have suggested that iodine status may not be as satisfactory in the UK – affluent southern counties of England – as previously thought (2). So the recently reported evidence of cognitive impairment in children of 8–9 years associated with poor maternal iodine status at the time of the children’s birth needs to be considered carefully (3). Foods may not actually be deficient in certain nutrients but may contain antagonists such as phytate or polyphenols in whole cereals, tea, coffee etc. and block absorption of minerals such as non-heme iron and zinc (4). Thus, bioavailability affects dietary iron, but it is also a factor influencing vitamin A status. The main dietary source of vitamin A for most people in the world is the provitamin A beta-carotene in green vegetables and fruits. Beta-Carotene is found within the cells of plant tissue, and to become available for absorption, the cellulose cytoskeleton needs to be broken up mechanically or by chewing and the beta-carotene released by heat and oil. However, too much heat can destroy the carotenoid and other micronutrients so overcooking can be counterproductive (5). Iron and vitamin A deficiencies continue to exist as many factors need to be corrected to ensure satisfactory absorption. In contrast to a deficiency of iron – the leading cause of anemia worldwide – and vitamin A – causing blindness – the successful supply and use of iodized salt helps to prevent the harmful effects of deficiency. However, in some European countries where salt iodization and iodine supplementation are not actively promoted, surveys are revealing evidence of mild to moderate iodine deficiency in pregnant women (6–8), which has been associated with cognitive impairment in their children (3).
The researchers commented that poor diets and micronutrient deficiencies can cause diseases and have potentially grave economic consequences for the individual, the family, the community and, if the condition is widespread, for the entire country. The type of food available will often determine which nutrient deficiency is of greatest importance. The main risk factors for micronutrient malnutrition are monotonous diets, poor bioavailability, little opportunity for diversification, low intakes of animal-source foods, low prevalence of breastfeeding and low micronutrient density in complementary foods. No staple food contains all the essential micronutrients.
14 March 2012
Older adults with a higher body mass index have lower vitamin D levels, which needs to be taken into account when determining an adequate dietary vitamin D intake, a new UK study suggests.
15 September 2014
Discussions about the sense and nonsense of dietary supplements take place regularly. Studies suggesting that high doses of vitamins and minerals may even shorten lives are gladly taken up by the media and enhance this dispute, the result of which being that many consumers who had previously been promised a health benefit of supplements are sometimes left feeling very uncertain.
8 August 2016
Recent headlines have warned women that vitamin supplements in pregnancy are a “pointless waste of money,” seemingly discouraging micronutrient supplementation at this crucial time. Check the story behind the headlines.