Knowledge of iodine nutrition

In contrast to the low level of knowledge of iodine nutrition in some countries, people in other countries seem to be better informed. In the Philippines, awareness regarding the importance of iodized salt consumption was 81%, while consumption was much lower at 21% (Tuazon and Habito, 2007). Awareness rates were of similarly high magnitude in Iran, where it was also found that literate women were more likely to use iodized salt in the household than iUiter-ate women (Sheikholeslam, 1996). 

From these limited examples, it appears that the knowledge level of iodine nutrition varies virtually from one extreme to the other in different countries. These variable knowledge levels have the potential to impact not only on the iodine status of the population, but also on the sustainability of national salt iodization programs. Because knowledge of iodine nutrition is viewed as one of the important determinants in the success of salt iodization programs, we take an in-depth look at the fundamentals of iodine knowledge in this chapter. 

Hardly any information is available on the knowledge of iodine nutrition among wholesalers and retailers. As a group they are probably the least informed about iodine nutrition and the consequences of iodine deficiency or excess (Ling, 2004). Only in circumstances where repackaging occurs, and in wholesaler or large retailer companies with in-house quality control laboratories, may one find some awareness of iodine nutrition and an awareness of legal requirements and consumers iodine health. 

In addition, the supply of iodized salt in the Phifippines was short because of a low production rate of iodized salt despite adequate capacity, which in turn was attributable to a low public demand for iodized salt, in a situation where abundant noniodized, cheaper salt was available. This example illustrates a number of factors that may play a role in the discrepancy sometimes seen between iodine knowledge level and behavior. More factors may be present in other countries, but the message for program managers is to be watchful for these factors that may weaken the iodine program, even when knowledge of iodine nutrition is satisfactory. 

Small producers pose an even greater challenge to educate, because their subsistence operations with small turnovers and modest profits leave little room for additional expenses such as iodization. In addition, their salt is invariably of inferior quality, making iodization less effective. Despite these potential barriers, they should share in the iodine-related information flow and have exposure to educational activities that may improve their iodine knowledge and positively influence their attitude and perspective of iodine nutrition and iodization of salt. 

In this situation of deficiency, iodized salt plays a very important role, the average UIE of the women who included it in their diet was higher than 200 pg/1 whereas in the rest it was below this critical level. Almost two thirds of the women not using iodized salt are iodine deficient as opposed to the 20% who do use it. In other words, iodized salt intake has a positive effect on the nutritional status of iodine in the pregnant women, but it is insufficient as the only source of iodine. Nevertheless, this observation has a limited reliability since, frequently, people lacking knowledge confuse iodized salt with noniodized salt, labeled as marine salt, and almost 23% of the women do not know what kind of salt has been bought for home consumption. 

The monitoring program of iodine intake and thyroid diseases (DanThyr) was designed to secure optimal iodine nutrition of the Danish population, and also to improve knowledge on how to evaluate the iodine status of a population. Moreover, the design would give information on the epidemiology of thyroid disorders in areas with different levels of iodine intake, and the effects of an increase in iodine intake. An additional aim was to clarify the role of various environmental factors for the development of thyroid disease in the population, and in particular to study how these factors may interact with iodine intake. 

Several minerals are essential in small amounts (micronutrient minerals). Of these, four—iron, copper, zinc, and iodine—are allowed to be listed on Nutrition Facts labels, iron being mandatory and the others optional. Other minerals known to be essential are selenium, manganese, fluorine, chromium, and molybdenum. Still other minerals (10 or more) are known to be essential in other mammals and are present and probably essential in humans. The list of trace minerals and our knowledge of their functions are constantly evolving. 

Is iodine insufficiency of current parenteral nutrition regimens potentially compromising the brain development of extreme and preterm infants when it is their only, or predominant, source of nutrition The determination of the iodide requirements of extreme preterm infants, and the safe levels of iodide supplementation necessary to achieve optimal blood levels, requires carefully piloted and designed clinical trials so that iodine toxicity is avoided. We have started this program of work (Ibrahim et al., 2003) and extended our knowledge through three further pilot studies in infants <30 weeks gestation. 

Twenty years ago it may have been quite difficult to justify the word "importance in the title of this paper. Though the clinical significance of iron and iodine deficiencies was appreciated, this did not apply to the broader concept of "trace element nutrition" as a whole. However, while many gaps in our knowledge remain, recent progress has been very substantial. As a consequence, it is unnecessary to start with any justification of the relevance of human trace element nutrition. Rather, I will proceed directly to a consideration of the special importance of trace element nutrition during the years of growth. 

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