Safety of micronutrients – Part 1: fat-soluble vitamins
Excessive intake of high-energy macronutrients and their potential consequences for people’s health are a problem in many industrial nations. In the case of micronutrients, however, epidemiological data suggests that over-supply is the exception rather than the rule across the globe. Many people are therefore concerned that their dietary habits are failing to provide them with a sufficient supply of essential nutrients such as vitamins and carotenoids. Given that intakes of some nutrients are below officially recommended levels, it might at first sight appear unnecessary to set upper intake levels for micronutrients. However excessive intake of food supplements and fortified foods in addition to normal diets could conceivably lead to intake levels which could potentially be considered harmful. It may be sensible to define an upper daily intake level at which the risk of adverse effects on health is unlikely, particularly in the case of fat-soluble vitamins which are stored in small quantities in the body.
The role of maternal nutrition during pregnancy for fetal development
Maternal nutritional status, diet and exposure to environmental factors are increasingly acknowledged as potential factors affecting fetal growth, both by altering nutrient availability to the fetus and by modulating placental gene expression, thus modifying placental function. Study results show that many pregnant women do not follow an appropriate diet in pregnancy, having insuf-ficient intakes of micronutrients, particularly iron, omega-3 fatty acids and folate, as well as calcium and vitamin D. This may negatively affect fetal growth both directly and indirectly.
A new US study reports that the regular intake of fish oil supplements may produce beneficial structural changes in the brain, countering age-related brain shrinkage.
A new study from Greece reports that high blood vitamin D concentrations seem to increase the exercise performance of professional soccer players.