A comparison of food portion size estimation by older adults, young adults and nutritionists

Abstract

Abstract:Objectives: To investigate the ability of older adults, younger adults and nutritionists to assess portion size using traditional methods versus a computer-based method. This was to inform the development of a novel dietary assessment method for older adults "The NANA system". Design: Older and younger adults assessed the portion size of self-served portions of foods from a buffet style set up using traditional and computerised portion size assessment aids. Nutritionists assessed the portion size of foods from digital photographs using computerised portion size aids. These estimates were compared to known weights of foods using univariate analyses of covariance (ANCOVA). Setting: The University of Sheffield, United Kingdom. Subjects: Forty older adults (aged 65 years and over), 41 younger adults (aged between 18 and 40 years) and 25 nutritionists. Results: There was little difference in the abilities of older and younger adults to assess portion size using both assessment aids with the exception of small pieces morphology. Even though the methods were not directly comparable among the test groups, there was less variability in portion size estimates made by the nutritionists. Conclusion: Older adults and younger adults are similar in their ability to assess food portion size and demonstrate wide variability of estimation compared to the ability of nutritionists to estimate portion size from photographs. The results suggest that the use of photographs of meals consumed for portion size assessment by a nutritionist may improve the accuracy of dietary assessment. Improved portion size assessment aids are required for all age groups.

Feasibility of Reviewing Digital Food Images for Dietary Assessment among Nutrition Professionals

“…The high work commitment and time constraint may have caused a high drop out among the recruited nutrition professionals. This response rate, however, is higher than a previous study on nutritionists [ 18 ], and the sample size seems to be larger than the typical sample size (10 to 25 participants) presented in previous nutrition estimation studies conducted among registered nutritionists or dietitians [ 15 , 18 , 20 ]. We acknowledge that our modest sample size may have limited statistical power to detect small weight differences for some food items.…”

“…Rice, as the staple for Malaysians, is the common feature in all meals and thus often estimated with accuracy in diet records by the nutrition professionals. The consistent shapes and cuts of foods could also help in accurate portion size estimation of fruits [ 15 , 35 , 39 ]. Raw vegetables (e.g., cucumber, carrots, bean sprouts) were significantly under-estimated, while drinks and chicken were consistently over-estimated in both images.…”

“…The increased application of image-assisted and image-based dietary methods has heightened the need for accurate image review by human analysts. Food portion size estimation by nutritionists, who had undergone training in dietary assessment, specifically in portion size estimation were reported to be most accurate and had less variability compared to those without training [ 9 , 15 , 16 ]. However, very few studies have examined the reliability of nutrition professionals such as nutritionists or dietitians in assessing dietary intake based on food images [ 12 , 17 , 18 , 19 ].…”

“…However, very few studies have examined the reliability of nutrition professionals such as nutritionists or dietitians in assessing dietary intake based on food images [ 12 , 17 , 18 , 19 ]. To date, only five studies have examined the accuracy of trained human analysts in reviewing food images for dietary assessment, albeit among nutritionists [ 15 ], dietitians [ 12 , 20 ], nutrition students [ 21 ], dietetic students and interns [ 22 ] in a Western context. The receptiveness of nutrition professionals towards image-assisted or image-based methods and their ability to review food images also remain unknown.…”

A Comparative Study on Carbohydrate Estimation: GoCARB vs. Dietitians

“…Thus, it was concluded that nutrition students need more training, in order to quantify the portion size more accurately. Lastly, a comparison study that was implemented between older adults, young adults, and nutritionists regarding portion size estimation, showed that the nutritionists achieved more accurate results when compared to the other groups [ 27 ]. In the current study, we compared the visual estimation of dietitians with the GTR and showed that food items, such as pasta, rice, and chips are difficult to estimate, which corroborates previous observations [ 28 ].…”