Objectives. To determine if an omega-3 food frequency questionnaire (FFQ) will provide a valid estimate of omega-3 fatty acid intake in overweight and obese pregnant women when compared to biomarker values.
Design. Cross-sectional validation study
Subjects. Twenty-seven overweight and obese pregnant women (pre-pregnant BMI > 25) between 18 and 40 years old were recruited from the greater Cincinnati area.
Methods. An omega-3 FFQ was administered, and a fasting venous blood sample was collected to assess erythrocyte fatty acid levels in 27 pregnant women in the last trimester of pregnancy. Average intake for total omega-3 fatty acids, alpha-linolenic acid (ALA), docosahexaenoic acid (DHA), and eicosapentaenoic acid (EPA) were calculated and compared to erythrocyte concentrations of the same fatty acids. The mean intake of DHA was also calculated and compared to the recommended intake levels for pregnant women.
Results. Dietary DHA intake was significantly correlated with both total omega-3 (r = +0.491, p < 0.01) and DHA (r = +0.438, p < 0.05) in the red blood cell. There was no significant correlation between dietary intake of total omega-3 fatty acids, ALA, or EPA and erythrocyte concentrations of the same. Mean DHA intake levels for this sample were 75 mg/day, significantly lower than the recommended level of 200 mg/day.
Conclusion. The omega-3 FFQ was a valid tool for assessing DHA status in overweight and obese pregnant women.
Acknowedgements. Supported in part by USPHS Grant #UL1 RR026314 from the National Center for Research Resources, NIH and NIH, R21 HL093532-0231.