Decision-making patterns for dietary supplement purchases among women aged 25 to 45 years

Testing the Impact of Familiarity with Health Benefits Information on Dietary Supplement Choice in Pregnancy: An Online Choice Experiment

To help meet the increased requirements for critical nutrients during and around pregnancy, supplementation with essential nutrients is recommended. This study aims to determine how the previous awareness of nutrient health benefits and/or the provision of this information influences the importance placed on nutrients (folate, iodine, omega-3 fatty acids, and vitamin D) when choosing between dietary supplement products for pregnancy. Discrete choice experiment data were collected as part of a cross-sectional online survey administered to 857 pregnant women living in Australia. Four segments of women were identified that differ in their preference criteria when choosing among dietary supplement products for pregnancy. When choosing between products, the reinforcement of perceived health benefits (i.e., showing information on health benefits to those already aware of the benefits) was most effective at increasing the importance of folate (in all segments) and iodine (in two segments, 63% of the sample). Neither prior awareness of health benefits alone nor information provided at the point-of-purchase without prior awareness were enough to increase the importance of folate. Our findings suggest a need for simultaneous strategies that (1) provide information on health benefits before purchase and (2) ensure that information on health benefits is available at the point-of-purchase.

Individual differences in the conceptualization of food across eating contexts

Individual differences in food-related knowledge structures were explored by applying schema theory to examine the categories 42 adults used to classify foods across four eating contexts. Food card-sort labels were organized into 12 categories, category salience for each person was evaluated, and cluster analysis was used to identify clusters of participants according to the salience of their categories. Clusters were further evaluated for complexity and consistency of category use across contexts. Seven food schema clusters were identified. Meal/time and Routine categories were the most salient overall and were used by most clusters. Well-being, Person, Source, Convenience, Meal component, and Food group categories varied in salience across clusters. The complexity and consistency of the food categories participants used across the contexts varied among the clusters. This study provided insight about cognitions that may underlie food-choice behaviors. Understanding individuals' food schemas could help nutrition professionals tailor messages to maximize health impact.

Limited agreement exists between rationale and practice in athletes' supplement use for maintenance of health: a retrospective study

Background

The widespread use of nutritional supplements among athletes is poorly understood. The prevalence of supplement intake and users' knowledge have been researched independently leading to useful, but disconnected, information on supplement use.

Methods

The 'UK Sport 2005 Drug Free Survey' data (n = 874) were re-analysed using association [χ²] and 'strength of association' tests [φ], to discover observed incongruencies between self-reported supplement use and the underlying motives. Results are given for test pairs between 'motive for use' [doctor's advice, avoiding sickness, overcoming injuries and enhancement of diet] and each supplement used and these were categorized as strong (φ > .7), intermediate (7 < φ > .3) and weak (φ < .3).

Results

The use of selected supplements varied widely as follows: multivitamin (72.7%), vitamin C (70.4%), echinacea (30.8%), iron (29.8%), magnesium (11.0%) and ginseng (8.3%). Associations with motive were found in 8 of the 10 test pairs which were expected from literature precedents, however only weak associations exist. Of these, four were associated with avoidance of sickness [iron (χ² = 11.94, p < .001; φ = .15, p = .001), multivitamin (χ² = 6.43, p < .001; φ = .11, p = .011), vitamin C (χ² = 54.67, p < .001; φ = .32, p < .001) and echinacea (χ² = 40.34, p < .001; φ = .28, p < .001)]. The remaining 4 associations were: no time to prepare meals with ginseng (χ² = 7.64, p = .006; φ = .12, p = .006) and multivitamin (χ² = 9.103, p = .003; φ = .13, p = .003); overcoming injuries with magnesium (χ² = 6.99, p = .008; φ = .11, p = .008); doctors' advice and iron (χ² = 35.00, p < .001; φ = .25, p = .001).

Conclusion

These results suggest a lack of understanding regarding supplements and health maintenance, except for vitamin C and echinacea. Furthermore, supplement use is apparently independent of physicians/dieticians' advice, except for iron. This may suggest a widespread circumvention of expert advice in the growing area of supplement use and therefore should be addressed to underscore potential health risks.

Supplement use in sport: is there a potentially dangerous incongruence between rationale and practice?

BACKGROUND

Supplement use by athletes is complex and research supports the alarming notion of misinformed decisions regarding supplements.

HYPOTHESIS

A frequent divergence between the type of supplements chosen by athletes and the rationale dictating the supplement use is hypothesized. Thus, a potentially dangerous incongruence may exist between rationale and practice.

TESTING THE HYPOTHESIS

In the continued absence of reliable data on supplement use, an alternative approach of studying the reasons underlying supplement use in athletes is proposed to determine whether there is an incongruence between rationale and practice. Existing data from large scale national surveys can be used to investigate this incongruence.

IMPLICATIONS OF THE HYPOTHESIS

In this report, analyses of distinctive patterns between the use and rationale for use of supplements among athletes are recommended to explore this potentially dangerous phenomenon.