To determine the impact of contaminant iron and geophagy on iron intake and status of persons living in developing countries.

Literature for review was identified by searching Medline and Agricola, from appropriate other texts and from three reports from the Opportunities for Micronutrient Interventions (OMNI) Project of USAID.

The dietary intake of iron by people living in developing countries is generally high but iron deficiency remains prevalent. This apparent paradox is because the iron being consumed is predominantly in the non-haem form, which is poorly absorbed. Some of this non-haem iron is from contamination of food with iron from soil, dust and water; iron leaching into food during storage and cooking; contamination during food processing such as milling; and the practice of geophagy.

Although the contribution of contaminant iron to overall iron intake is well documented, its absorption and thus its impact on iron status is not. To be available for absorption, contaminant iron must join the common non-haem pool, i.e. be exchangeable. The absorption of exchangeable contaminant iron is subject to the same interactions with other constituents in the diet as the non-haem iron that is intrinsic to food. The limited available evidence suggests wide variation in exchangeability. In situations where a significant fraction of the contaminating iron joins the pool, the impact on iron status could be substantial. Without a simple method for predicting exchangeability, the impact of contaminant iron on iron status in any particular situation is uncertain.

Interventions known to increase the absorption of iron intrinsic to foods will also increase absorption of any contaminant iron that has joined the common pool. Any positive effect of geophagy resulting from an increased intake of iron is highly unlikely, due to inhibiting constituents contained in soils and clays. The efficacy of approaches designed to increase the intake of contaminant iron remains encouraging but uncertain. An approach using multiple interventions will continue to be essential to reduce iron deficiency anaemia.

This paper provides a comprehensive review of the changes in the prevalence and the extent of anaemia among different population groups in Bangladesh up to the present time. The report also focuses on various factors in the aetiology of anaemia in the country.

All the available data have been examined in detail, including data from national nutrition surveys, as well as small studies in different population groups.

Over the past three decades a number of studies including four national nutrition surveys (1962/64; 1975/76; 1981/82 and 1995/96) have been carried out to investigate the prevalence of anaemia among different population groups in Bangladesh, and have demonstrated a significant public health problem. Since the 1975/76 survey the average national prevalence of anaemia has not fallen; in 1995/96, 74% were anaemic (64% in urban areas and 77% in rural areas). However, age-specific comparisons suggest that the rates have fallen in most groups except adult men: in preschool children in rural areas it has decreased by about 30%, but the current level (53%) still falls within internationally agreed high risk levels. Among the rural population, the prevalence of anaemia is 43% in adolescent girls, 45% in non-pregnant women and 49% in pregnant women. The rates in the urban population are slightly lower compared with rural areas, but are high enough to pose a considerable problem. It appears that severe anaemia in the Bangladeshi population is less frequent, possibly present among only 2–3% of the population. The data on the aetiology of anaemia reveal that iron deficiency may be a substantial cause of anaemia in the Bangladeshi population. Other dietary factors in addition to parasitic infestations may also precipitate the high prevalence of anaemia.

While the overall prevalence of anaemia among the Bangladeshi population is still very high, the rates of severe anaemia are almost non-existent. A large proportion of anaemia can be attributed to iron deficiency. There is a need for a comprehensive strategy for the prevention and control of anaemia in Bangladesh.

To identify risk factors for variation in serum retinol levels in children younger than 2 years of age in a rural South African community.

Children (n=97), 6–24 months of age, were divided into two groups according to their serum retinol levels, using 20 μg dl−1 as the cut-off point. The chi-square test, Fischer exact two-tailed test and analysis of variance were used to identify related variables which were significantly different between the two groups. To evaluate simultaneously the association between several potential risk factors and low serum retinol levels, a multiple regression model for categorical data was developed which included potential risk factors that were statistically significant in the bivariate analysis as the independent variables, and either low or normal vitamin A status as the dependent variable.

There was an association between serum retinol levels and: (i) the place of birth (hospital vs. home deliveries); (ii) the attitude of the care-giver towards family life; and (iii) the health status of the child. Although not included in the multiple variable model because of small numbers, all children who had a previous episode of measles, all underweight children, and all children of widowed care-givers were in the low serum retinol group.

The care-giver's attitude towards family life was positively associated with the child's vitamin A status, while home deliveries were associated with a low vitamin A status.

To identify influences on type of milk consumed and the impact of milk choice on calcium intakes in Australian women of pre- and postmenopausal age.

Questionnaires covering calcium intake, health-related dietary issues and priorities self-completed in a group setting.

A total of 300 women recruited from community groups and government departments.

Mean milk and calcium intake were higher in older (≥50 years) compared to younger women. Milk provided over 50% of calcium intake for both groups. Participants rated the importance of eating foods low in fat, energy or cholesterol, high in calcium or dietary fibre or of ‘limiting their intake of added sugar or sugary foods’. Younger and older women ranked eating foods low in fat as the most important food habit for their health, then ranked dietary fibre next in importance. Calcium ranked third for younger women, and fourth for older women. These rankings were reflected in the higher proportion of older women choosing fat-reduced milk in general, and skim milk in particular. This concern about eating foods low in fat was consistent with the choices made of skim, reduced fat/higher calcium or whole milk.

Results from this study suggest that concerns about fat are prejudicing the type of milk and amount of calcium consumed. Public health strategies targeting calcium intake need to address age-related differences in quantity and type of milk consumed, including the food attribute conflicts influencing these.

To evaluate the impact of nutrition education promoting lower dietary fat on the overall diet quality in children using a multidimensional index that measures nutrient and food intakes in relation to US dietary recommendations.

Prospective cohort study with two intervention and two control groups. Children with elevated low density lipoprotein (LDL) cholesterol were randomized to one of two intervention groups or an at-risk control group. The intervention children received either the parent–child autotutorial (PCAT) programme, a 10-week home-based self-instruction nutrition education programme, or nutrition counselling from a registered dietitian. Children with non-elevated plasma cholesterol formed the not-at-risk control group. Dietary and blood data were collected at baseline and at 3 months.

Paediatric practices in suburbs north of Philadelphia, PA.

Two hundred and twenty-seven 4–10-year-old children with elevated LDL cholesterol between the 80th and 98th percentiles, and 76 age- and gender-matched children with non-elevated plasma cholesterol, were studied.

Children who received PCAT or counselling significantly improved their overall diet quality (−0.6 and −0.4 change in diet quality index (DQI) scores) compared with at-risk control children. Children who received either form of nutrition education were more likely to meet the recommendations for three components of the DQI (total fat, saturated fat, sodium) (OR <1.7), but did not improve their intakes of three components of the DQI (vegetables and fruits, complex carbohydrates, calcium) at 3 months.

Nutrition education promoting lower dietary fat improved children's overall diet quality. However, several dietary behaviours important for long-term health remained unchanged.

To assess weight perceptions, weight concerns and weight control behaviours and related beliefs in a representative sample of adults.

Cross-sectional postal survey.

The survey was conducted between October and December 1997 in the state of Victoria, Australia.

A total of 2500 subjects were selected at random from the Australian electoral roll; 900 provided usable responses.

At the time of the survey, 2.7% of respondents were trying to gain weight, 26.6% were trying to avoid gaining weight, 22.9% were trying to lose weight and 47.9% were not doing anything for their weight. Men (47.2%) were less likely than women (55.3%) to be attempting any form of weight control. Watching the type of food eaten (95.6%), reducing dietary fat intake (87.3%) and engaging in physical activity or exercise (84.4%) were the most common weight control strategies used. Potentially harmful strategies, such as self-induced vomiting and smoking, were used by relatively few respondents. Many adults believed that vigorous activity (26.8%) and total omission of fat from the diet (35.3%) are necessary in order to lose weight.

Attempts at weight control are common in the community. However, many men, including men who are already overweight, appear to be unconcerned about their weight. Obesity prevention initiatives should attempt to influence individuals' weight-related beliefs and behaviours, as well as seeking to change policies and environments to better support weight control.

To evaluate the long-term effects of a horticultural and nutrition education intervention in rural Tanzania.

A quasi-experimental post-test design was used.

The research was carried out in 10 villages in Singida region, Tanzania.

Mothers and their children aged 6–71 months (n = 236) from an experimental (Ilongero) and control (Ihanja) area were interviewed regarding knowledge and practices related to vitamin A nutrition. Intake of vitamin A-rich foods by the children during the 7 days prior to the interview was recorded. Stools were examined for helminths and serum samples were analysed for retinol and C-reactive protein (CRP) (n = 146) for the children aged 12–71 months.

Knowledge and practices were more favourable to vitamin A intake in the experimental area than in the control area, and an increased frequency of intake of green leaves was associated with higher serum retinol values. The experimental area had lower mean serum retinol levels (13.7 μg dl−1, n = 75) than the control area (19.3 μg dl−1, n = 71). One likely confounder was the higher helminth infestation in the experimental area (n = 75, 79%) than in the control area (n = 71, 49%) (P > 0.001). Children with helminths (n = 94) had a lower mean serum retinol level than those without (n = 52) (12.3 ± 5 vs. 24 ± 10 μg dl−1; P = 0.001).

Food-based vitamin A programmes can make sustainable improvements in knowledge and dietary practices but these may not necessarily be reflected in increases in serum retinol. Programme implementation and evaluation should take confounders into consideration as, in this case, helminth infestation.

To examine risk factors for poor iron status in British toddlers.

National Diet and Nutrition Survey (NDNS) of children aged 1.5–4.5 years.

Mainland Britain, 1992/93.

Of the 1859 children whose parents or guardians were interviewed, a weighed dietary intake was provided for 1675, and a blood sample obtained from 1003.

Mean haemoglobin (Hb) and ferritin levels were significantly lower in younger (1.5–2.5 years) than in older (3.5–4.5 years) children, with boys having significantly lower ferritin levels than girls. Poor iron status (Hb>110 g l−1, ferritin >10 μg l−1, or low values for both indices) was associated with lower socioeconomic and employment status. Iron status was directly associated with meat and fruit consumption and inversely with that of milk and milk products, after adjustment for age and gender. The latter association remained significant after further adjustment for sociodemographic variables, energy intake and body weight. Children consuming <400 g day−1 of milk and cream were less likely to consume foods in other groups, with those also consuming little meat, fish, fruit and nuts at greatest risk of poor iron status. Few associations were observed between poor iron status and individual nutrient intakes, and iron status was not associated with either iron intake or with consumption of a vegetarian diet.

Overdependence on milk, where it displaces iron-rich or iron-enhancing foods, may put toddlers at increased risk of poor iron status. However, this becomes non-significant when moderate-to-high amounts of foods known to enhance iron status (e.g. meat and/or fruit) are also consumed. Milk consumption in this age group should ideally be part of a mixed and balanced diet including all food groups, and particularly lean meat (or other iron-rich or fortified foods) and fruit. This is particularly relevant for households of lower socioeconomic and employment status.