The use of novel foods enriched with long-chain n-3 fatty acids to increase dietary intake: a comparison of methodologies assessing nutrient intake.

OBJECTIVE: To evaluate the effect of consuming a variety of foods enriched in long-chain n-3 fatty acids in low fish eaters. DESIGN: Evaluation of reported dietary intakes in a 6-month, double-blind, randomized, controlled parallel design trial. SUBJECTS/SETTING: Eighty-five men and women with overweight and mildly elevated triglyceride levels who have a low habitual intake of fish. INTERVENTION: Subjects were randomized to consume foods either enriched in long-chain n-3 fats or control foods (not enriched). Subjects were asked to consume eight portions per day (equivalent to approximately 1 g/day long-chain n-3 fatty acid if randomized to the intervention). MAIN OUTCOME MEASURE: Reported energy, macronutrient, and fatty acid intakes were measured by diet history, 3-day food records, and body weight. STATISTICAL ANALYSES: Repeated measures analysis of variance, Kruskall-Wallis test, Pearson's correlation coefficient, and Bland-Altman plots were conducted. RESULTS: The two groups did not differ in mean dietary intake of long-chain n-3 fatty acid intake at baseline (258 mg and 313 mg for the intervention and control groups, respectively). At 6 months the intervention group members increased their intake of long-chain n-3 fats 4.5-fold compared with baseline and with the control group (P<.001). The data from the diet histories correlated well with the food records for all reported macronutrient and fatty acid values. Food pattern analysis showed that milk (13.8%), cereal (12.1%), and bread (11.3%) contributed the most to the overall long-chain n-3 fatty acid intake in the intervention group. CONCLUSIONS: This long-term study in free-living subjects indicates that population intakes of long-chain n-3 fatty acids could be substantially increased through the availability of a variety of n-3 fatty acid-enriched processed foods.