Selenium and zinc status are suboptimal in a sample of older New Zealand women in a community-based study.

The importance of selenium and zinc in the immune functioning of the aged is widely recognized. Seniors in New Zealand are at particularly high risk of low selenium status because of the low selenium soil environment. The zinc status of the New Zealand elderly has never been assessed. In this cross-sectional study, the biochemical selenium, zinc and lipid levels, physical functional capacity and dietary intakes of 103 randomly selected free-living New Zealand women (mean age +/- SD, 75 +/- 3 y) were assessed. Among nonusers of selenium supplements (n = 80), 80% [95% confidence interval (CI): 70; 88%] had plasma selenium levels (0.85 +/- 0.23 micromol/L) below 1.00 micromol/L [ approximately 10% below mean plasma selenium necessary for full expression of glutathione peroxidase (GPx) activity in New Zealand subjects]. Plasma selenium was strongly correlated with GPx: r = 0.56; P < 0.0001. For nonusers of zinc supplements (n = 88), serum zinc concentrations were 12.4 +/- 1.4 micromol/L, with 12% (95% CI: 6; 21%) having levels below the cut-off value (10.7 micromol/L). Estimated mean daily selenium and zinc intakes were 34 +/- 10 microg and 8.7 +/- 2.0 mg, respectively. Subjects in the highest tertile of a functional capacity index had higher biochemical zinc and selenium values than those in the lowest tertile (P < 0.05). The correlation between plasma selenium and GPx indicates that selenium intake in these women is still insufficient for full expression of GPx activity. Lower serum zinc levels also appear to be prevalent. Because a suboptimal trace element status may be more common among those with a poor physical functioning, promotion of the consumption of nutrient dense foods or supplements to improve selenium and zinc status of elderly women in New Zealand may be beneficial.

Attention is needed to the high prevalence of vitamin D deficiency in our older population.

The aim of this study was to assess the prevalence of vitamin D deficiency in females residing in one large, aged-care facility in Auckland. Thirty-nine residents, most of whom were able to go outdoors without assistance, were tested for midwinter 25-hydroxyvitamin D, and, of these, 36 were tested again in midsummer. The prevalence of frank hypovitaminosis (<10 microg/L) was found to be 49% in midwinter and 33% in midsummer. The vitamin D status of such at-risk individuals could be normalised either by 15-30 minutes of daily sun exposure or, alternatively, a programme of supplementation.

Validity of a short food frequency questionnaire for estimating nutrient intake in elderly people.

Nutrient intakes estimated using a short self-administered semi-quantitative food frequency questionnaire (FFQ) were compared with results obtained from five 2 d diet records using household measures in a group of fifty-three elderly people (mean age 70 years) in Dunedin, New Zealand in 1989. Mean intakes for most nutrients were less than 5% different between the two methods. Correlations between the nutrient intake values (excluding supplements) from the diet records and those from the FFQ ranged from 0.34 for Zn in women to more than 0.75 for protein, Zn and Ca in men. For most nutrients, at least 70% of the subjects when classified by the food records fell into the same quintile or into the within-one-quintile category when classified by the FFQ. These data indicate that in elderly subjects a simple self-administered semi-quantitative FFQ can provide very similar information (for both group and individual intakes for many nutrients) to that obtained from 10 d of careful diet recording.

Dietary supplement use in a randomly selected group of elderly Australians. Results from a large nutrition and health survey.

The prevalence of dietary supplementation and its relationship to health and dietary habits was investigated in a random mail survey of 2,195 people aged 65 years and over in Adelaide, South Australia. Subjects were selected from the electoral rolls in an urban area, and 77% returned completed survey instruments. Thirty-five percent of men and 46% of women reported taking some form of supplement at least once a week regularly throughout the year (these are defined as "regular" supplementers). The most popular supplements (in descending order of popularity for the total group) were: unprocessed bran, wheatgerm, vitamin C, and multivitamins or minerals. Thirteen percent of men and 15% of women reported the use of supplements on an occasional basis (once every few months or "now and then")--these are defined as "irregular" or "occasional" supplementers. Supplement users did not differ from non-supplementers in their use of medical facilities or in the number of bouts of minor illness they had experienced in the preceding year. Regular supplement users had more favorable dietary habits and higher intakes of several vitamins, minerals, trace elements and fiber than either non-supplementers or occasional supplementers.