Validation of a photographic seafood portion guide to assess fish and shrimp intakes

OBJECTIVE To validate a novel photographic portion guide as a tool to estimate consumption of fish and shrimp. Application of such a validated tool can facilitate accurate individual and community seafood intake assessments and provide meaningful data relative to health benefits and hazard assessment, particularly in response to environmental contamination and disasters. DESIGN A photographic fish and shrimp portion guide presenting a stepped range of cooked portion sizes was used by participants to estimate their typical portion sizes. Participants selected their typical portion size from the photographic guide and also from a selection of freshly cooked reference meals. Photographic portions selections were compared with plated reference portions for each participant. SETTING Academic sensory testing laboratory in the USA. SUBJECTS Separate groups of adults (25-64 years) contributed to fish (n 54) and shrimp (n 53) portion size comparison studies. RESULTS In the fish study, there was no difference between photographic portion selections (6·59 (sd 2·65) oz (186·8 (sd 75·1) g)) and reference plate selections (7·04 (sd 2·63) oz (199·6 (sd 74·6) g); P=0·384). Similarly in the shrimp study, there was no difference between photographic portion selections (6·88 (sd 3·40) oz (195·0 (sd 96·4) g)) and reference plate selections (6·06 (sd 2·65) oz (171·8 (sd 75·1) g); P=0·159). Photographic portions predicted plated reference portions for both fish and shrimp based on linear regression (P<0·001). Bland-Altman plot analyses showed good agreement between the two methods, <1 oz (<28·3 g) bias, in both fish and shrimp studies. CONCLUSIONS This validated photographic seafood portion guide provides a utilitarian tool for accurately assessing fish and shrimp intake in a community setting.