Re-evaluation of energy requirements in Canadian women over fifty years using doubly-labelled water and multimedia diet records

• Main Author: Kaczkowski, Crystal H.
• Other Authors: Jones, Peter J. H. (advisor)
• Format: Others
• Language: en
• Published: McGill University 1999
• Subjects: Diet > Canada.; Older women > Nutrition.; Women > Nutrition.
• Online Access: http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=21577

Dietary assessment methods are often plagued with inconsistent or inaccurate data. Self-reported intakes are particularly susceptible to error as research has shown that humans habitually report food intake inappropriately. Self-reported intakes have been used to create energy recommendations for populations. In order to assess energy intake, a novel 4 day multimedia dietary assessment method was developed utilizing a tape-recorder and camera in an attempt to more accurately quantify energy intake than traditional methods. The Recommended Nutrient Intakes for Canadians ( RNIC) provide population mean energy estimations. An objective was to determine whether the RNIC provides an accurate index of energy requirements. Current literature suggests that the RNIC is inadequate in some populations to meet energy needs when validated against methods such as doubly-labelled water (DLW). Total energy expenditure (TEE) and body composition were determined through the use of DLW in 76 women (49--93 years) over 13 days. The multimedia diet records did not reflect true intake in these subjects as demonstrated by a mean 24% underreporting rate when compared to TEE. Mean energy expenditure (MJ/day) as determined by doubly-labelled water was significantly higher (p < 0.01) in each stratified age range when compared to reported energy intake by multimedia diet records. The use of tabulated RNIC's underestimated true energy requirements by a mean of 29%. Food and Agriculture Organization/World Health Organization energy predictions closely estimated actual TEE in the study population. This research agrees with current literature questioning the validity of self-reported dietary intake data.