L Hallberg’s research while affiliated with Mid Sweden University and other places

European Journal of Clinical Nutrition is a high quality, peer-reviewed journal that covers all aspects of human nutrition.

Studies of the menstrual blood loss have been performed before by several authors. Usually these investigations have been based on small and selected series, involving hospital personnel or students. Early reports on menstrual blood loss were reviewed by Barer and Fowler (1936) and also by Frenchman and Johnston (1949). A summary of the reports after 1936 is given in Table I. The table shows that the series studied differed in many respects and that various technical procedures were used to determine the menstrual blood loss. Repeated measurements of consecutive periods were made in some investigations and a good agreement between the various periods in the same individual has been reported by most authors (Barer and Fowler, 1936; Leverton and Roberts, 1937; Frenchman and Johnston, 1949; Millis, 1951; Apte and Venkatachalam, 1963, and Hytten, Cheyne and Klopper, 1964). Other authors, however, have found a great variation between various periods in the same individual. Thus, Arens (1945) found that the menstrual blood loss varied from one period to another in 5 out of 7 women whose menstrual blood loss was measured more than once. S c h 1 a p p h o f f and John ston (I 949) also reported great variation between different periods in 6 girls aged 13 to 14 years. Baldwin, Whalley,

When it comes to iron balance and absorption the primary dietary aspects to consider are; iron bioavailability, and the amount of iron in the diet. When it comes to the scientific evidence for the comparative effect from each of these measures in improving iron balance in man, there are still questions. In 1994 Swedish millers decided to withdraw the voluntary iron fortification of all white wheat flour which had been carried out for 50 years. This unique situation made it possible to study the effect of iron fortification, and the effects of withdrawal of iron fortification among vulnerable groups in the population. To study the effects of the withdrawal of iron fortification, two cross-sectional studies were performed in Göteborg, Sweden. One in 1994 were a random sample of approximately 600 fifteen- to sixteen year-old girls was examined, and the other in year 2000 were another sample of girls of the same age was examined. Adolescents menstruating girls were chosen as a suitable model since they have high iron requirements as well as for menstrual losses. The primary outcome assessed before, and six years after the Swedish iron fortification withdrawal, was iron status. Also series of possible confounding factors were examined and eliminated such as differences in diet, use of contraceptive pills, physical activity, intake of iron supplements etc. The result showed that, in 1994, fortification iron from wheat flour represented almost 40% of the dietary iron intake. Six years after the withdrawal, the marked decrease in total iron intake led to a lower amount of available iron. During the same time, the prevalence of iron deficiency (serum ferritin <16 μg/L) increased from 39 before the withdrawal to 50% after the withdrawal, an increase of 28%. Considering differences in the diet, and composition of separate meals there was a slight decrease in dietary iron bioavailability. Taken together, the combined action of a decreased intake of fortification iron, and a dietary composition giving a lower dietary iron bioavailability, gave six years after iron fortification, an situation of decreased iron balance. This was also evident from the increased iron deficiency prevalence.

'Sports anemia' may best be regarded as a 'side-effect' of the hard training in endurance sports, a physiologic response of the regulatory systems controlling the hemoglobin concentration in blood to an unphysiologically heavy and prolonged exercise load.

Serum iron and total iron binding capacity (TIBC) were determined in a population sample of 1462 women in age strata between 38 and 60. Serum iron and TIBC values were similar in the various ages studied but with a slight trend towards higher serum iron and lower TIBC values in the upper ages. Transferrin saturation was used to divide the material arbitrarily into women with and without iron deficiency. The dividing point chosen was 16%. The women thus defined as iron deficient had lower mean haemoglobin values than women in the total population sample and were more often anaemic. They had also lower MCV, MCH and MCHC indices than women in the total population sample. Of these indices, MCH seemed to discriminate the state of iron deficiency better than MCV and MCHC. Except for an increased mean menstrual blood loss no obvious cause of iron deficiency could be found in these women with low transferrin saturation.

Abstract A population study of women in Gothenburg, Sweden, is presented. The women were representative of the total female population in Gothenburg in the age strata 38, 46, 50, 54 and 60 years. Altogether 1 462 women participated in the examination, the participation rate being 90.1%. Social data of participants and non-participants are given. The performance of the examination is described and research projects are outlined. It is concluded that the selection of a strictly representative sample, together with careful uniformity of performance and high participation rate, will make it possible to draw valid conclusions about the total population of middle-aged women in Gothenburg.