To describe the extent of use of medicines by older people living in Britain, and to explore relationships with vitamin status indices.

The National Diet and Nutrition Survey of people aged 65 years and over collected data from a British sample during 1994–95. The present study has made novel use of it, to relate medicine use with biochemical indices of vitamin status.

Eighty postcode areas, selected randomly from mainland Britain.

1506 people, 65 years and over gave information about use of medication, and a 4-day weighed food record. Three-quarters gave blood for status indices.

78% of those living in the community and 93% of those in institutions were using medication. Certain vitamin status indices: plasma retinol, erythrocyte folate and riboflavin, paradoxically suggested better status in users than in non-users of antihypertensive, gastrointestinal, central nervous system, corticosteroid or diabetic drugs. There was evidence of a link with renal insufficiency, especially for plasma retinol, but neither this nor increased nutrient intake, acute phase effects or haemoconcentration could explain the paradoxical associations.

Caution is needed in interpreting certain vitamin status indices, especially in older people who are extensively using medicines. New vitamin indices are needed, to avoid confounding interferences.

To determine the serum levels of three lipid-soluble antioxidants (retinol, β-carotene and α-tocopherol) in pregnant women attending an antenatal clinic (ANC) in Gondar, Ethiopia.

A cross-sectional study involving laboratory determination of serum levels of retinol, α-tocopherol and β-carotene using high-performance liquid chromatography and questionnaire-based assessment of socio-economic status.

ANC of a university teaching hospital.

Three hundred and twenty-two healthy pregnant women in their third trimester, who attended the ANC.

Mean serum levels of retinol, α-tocopherol and β-carotene were found to be 1.23±0.5, 25.5±0.9 and 0.21±0.09 μmol l−1, respectively. The prevalence of vitamin A deficiency (<1.05 μmol l−1) among pregnant women was 38.5%. Women having low retinol (vitamin A) levels were highly likely to live in earth-floored and mud-walled houses, and less likely to own a house and to have a latrine.

The study shows that serum levels of lipid-soluble antioxidants were low among ANC attendees in northern Ethiopia. It also indicates that some socio-economic factors (such as poor housing standard) are associated with vitamin A deficiency.

To validate intakes of protein, folic acid, retinol and n–3 fatty acids estimated from a food-frequency questionnaire in week 25 of pregnancy (FFQ-25).

Validation was done against a 7-day weighed food diary (FD) and biomarkers of the nutrients in gestation week 32–38.

The FFQ-25 to be validated was used in the Danish National Birth Cohort comprising 101 042 pregnant Danish women, of whom 88 participated in the present validation study.

Estimated intakes of protein, retinol and folic acid did not differ significantly between the two dietary methods, but intake of n–3 fatty acids was one third larger when estimated from the FFQ-25. The intakes estimated from the two dietary methods were all significantly correlated, ranging from 0.20 for retinol intake to 0.57 for folic acid intake. Sensitivities of being correctly classified into low and high quintiles were between 0.22 and 0.77, and specificities were between 0.62 and 0.89. Urinary protein content did not correlate significantly with protein estimated from the FFQ (r = 0.17, P > 0.05), but did with intake estimated from the FD (r = 0.56, P < 0.0001). Erythrocyte folate correlated significantly with the estimated total intake from the FFQ (r = 0.55, P < 0.0001) and the FD (r = 0.52, P < 0.0001). No correlations with plasma retinol were found. Erythrocyte eicosapentaenoic acid (C20:5n-3) correlated significantly with n–3 fatty acids intake estimated from both the FFQ-25 (r = 0.37, P < 0.001) and the FD (r = 0.62, P < 0.0001).

The FFQ-25 gives reasonable valid estimates of protein, retinol and folic acid intakes, but seems to overestimate intake of n–3 fatty acids.