Under- and overreporting of energy is related to obesity, lifestyle factors and food group intakes in Jamaican adults

Objective: Research in industrialised countries has documented a high prevalence of underreported energy intakes associated with characteristics such as obesity. This paper examines the prevalence, patterns and impact of energy under- and overreporting on diet-obesity relationships in a middle-income developing country. Design: A 70-item food-frequency questionnaire was used. Underreporters had reported energy intakes <1.35 X basal metabolic rate (BMR), overreporters > 2.4 X BMR. Multinomial models were used to identify characteristics associated with implausible reporting. Intakes were compared across reporting groups to assess evidence of bias. Associations between diet and obesity were compared with and without adjustment for implausible reporting. Setting: Spanish Town, neighbouring the capital city of Kingston, Jamaica. Subjects: Eight hundred and ninety-one Jamaican adults, aged 25-75 years, were randomly recruited. Results: More women than men (38.6% vs. 22.5%) underreported, but more men overreported energy (23.7% vs. 16.0%). Underreporting was positively associated with obesity, special diets, smoking and age; age was inversely associated with overreporting. Underreporters estimated lower energy from potentially socially undesirable food groups (e.g. snacks) and higher intakes of 'healthy' foods (e.g. fruit) than did plausible reporters. For some of these food groups, significant differences in intakes among normal-weight versus obese subjects observed among plausible reporters were absent when implausible reporters were included. in models of food group-obesity associations, adjusting for implausible energy yielded more credible results that more closely resembled findings in plausible reporters. Conclusions: Energy under- and overreporting are highly prevalent in Jamaica. Adjusting for implausible reporting may help to reduce bias in diet-health outcome associations.