To examine the prevalence and dietary, sociodemographic and lifestyle risk factors of low iron intake and poor iron status in British young people.

National Diet and Nutrition Survey of young people aged 4–18 years.

Great Britain, 1997.

In total, 1699 young people provided 7-day weighed dietary records, of which 11% were excluded because the participant reported being unwell with eating habits affected. Blood was obtained from 1193 participants, with iron status indicated by haemoglobin, serum ferritin and transferrin saturation.

Iron intakes were generally adequate in most young people aged 4–18 years. However, low iron intakes (below the Lower Reference Nutrient Intake) occurred in 44% of adolescent girls (11–18 years), being less prevalent with high consumption of breakfast cereals. Low haemoglobin concentration (<115 gl−1, 4–12 years; <120 or <130 gl−1, 13+ years for girls and boys, respectively) was observed in 9% of children aged 4–6 years, pubertal boys (11–14 years) and older girls (15–18 years). Adolescent girls who were non-Caucasians or vegetarians had significantly poorer iron status than Caucasians or meat eaters, independent of other risk factors. The three iron status indices were correlated significantly with haem, but not non-haem, iron intake.

Adolescent girls showed the highest prevalence of low iron intake and poor iron status, with the latter independently associated with non-Caucasian ethnicity and vegetarianism. Risk of poor iron status may be reduced by consuming (particularly lean red) meat or enhancers of non-haem iron absorption (e.g. fruit or fruit juice) in vegetarians.

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.

To examine the relationship between cigarette smoking and a range of nutrient intakes and blood status indices in older people.

National Diet and Nutrition Survey: cross-sectional survey of nationally representative sample of people aged 65 years and over.

Mainland Britain during 1994/95.

1191 people (619 male, 572 female) aged 65 years and over, of whom 920 were living in private households and 271 were living in institutions.

Cigarette smoking was inversely correlated with intakes of antioxidants and other micronutrients after adjustment for age, sex and domicile. Cigarette smoking was also inversely correlated with a number of antioxidant micronutrient status indices including plasma vitamin C and the carotenoids (but not vitamin E status indices), and with other micronutrient status indices, including plasma pyridoxal phosphate, red cell and serum folate, after adjustment for age, sex, domicile and the corresponding nutrient intake. Previous cigarette smoking or cigar/pipe smoking was not generally associated with lower nutrient intakes or status indices, however, both current and previous cigarette smoking was associated with increased concentrations of acute phase indicators. Further adjustment for total energy intake and/or sociodemographic, health and drug usage variables attenuated only a few of the associations observed.

Older people who smoke cigarettes are at increased risk of suboptimal antioxidant and other micronutrient intakes and status, but the lower intakes found in cigarette smokers only partly explain their reduced blood indices.

To examine the relationships between alcohol consumption and a range of nutrient intakes and blood status indices in older people.

National Diet and Nutrition Survey: cross-sectional survey of nationally representative sample of people aged 65 years or over.

Mainland Britain during 1994/5.

1198 people (623 males, 575 females) aged 65 years or over, of whom 925 were living in private households and 273 were living in institutions.

Intermediate alcohol consumption (particularly 0.1–14 units week−1; 1 unit = 8g) derived from a 4-day diet diary or a 12-month recall questionnaire, was associated with higher intakes of vitamins C, E, B1, iron, calcium, energy from food, carbohydrate and non-starch polysaccharides than heavy alcohol consumption (28 + units week−1) or abstinence, after adjustment for a number of factors (age, sex, domicile, social class, cigarette smoking, self-reported health, grip strength and total energy intake). Intermediate alcohol consumption was also associated with higher blood concentrations (independent of intake) of vitamin C, β-cryptoxanthin, lutein and calcium, with the lowest concentrations being found in heavy alcohol users. The lowest concentrations of serum ferritin were found in light drinkers and the highest levels in heavier alcohol drinkers. Alcohol consumption ranging from 0.1 to > 28 units week−1 was directly correlated with intakes of B vitamins, total energy and fat, with blood concentrations (independent of intake) of lycopene. high density lipoprotein (HDL)-cholesterol, plasma pyridoxal phosphate and retinol, and with blood pressure and grip strength.

Compared with abstinence and heavy drinking, light to moderate alcohol consumption in older people is associated with higher intakes of certain nutrients, and higher blood concentrations (independent of intake) of some micronutrient status indices, including antioxidants. The explanation for the latter associations remains unclear and further investigation is recommended. Heavier alcohol consumption is associated with both beneficial and adverse effects with respect to nutrient intakes and health status.