Plasma Concentrations of (n-3) Highly Unsaturated Fatty Acids Are Good Biomarkers of Relative Dietary Fatty Acid Intakes: A Cross-Sectional Study

Abstract

A cross-sectional study was conducted to clarify the associations of lifestyle factors (habitual exercise, alcohol intake and smoking habit) and plasma fatty acid (FA) concentrations as biomarkers of dietary FA intakes. We collected 7-d weighed diet records, lifestyle information and blood samples from 15 male and 79 female Japanese dietitians, and estimated dietary FA intakes and analyzed plasma FA concentrations. Plasma concentrations of eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) and (n-3) highly unsaturated FA (HUFA) derived from marine foods, but not linoleic and alpha-linolenic acid from plant origins, demonstrated positive correlations with dietary intakes (r = 0.303-0.602, P < 0.05) in both genders. Multiple linear regression analyses adjusted for age, BMI, total energy intake, fat (or respective FA) consumption and lifestyle factors showed that dietary intakes of EPA, DHA and (n-3) HUFA were positively associated with age in men (P < 0.05) and negatively associated with BMI in women [P < 0.01 for DHA and (n-3) HUFA]. The plasma concentrations of EPA, DHA and (n-3) HUFA in women were found to be positively associated with age and marine oil (or respective FA) intake (P < 0.01), and negatively associated with total energy intake [P < 0.05 for EPA and (n-3) HUFA]. Lifestyle factors were not associated with dietary FA intakes and plasma FA concentrations. These findings suggest that the plasma concentrations of EPA, DHA and (n-3) HUFA might be useful biomarkers for the assessment of relative FA intakes without considering associations with habitual exercise, alcohol intake and smoking habit.

Plasma n-6 and n-3 polyunsaturated fatty acids as biomarkers of their dietary intakes: a cross-sectional study within a cohort of middle-aged French men and women

“…The mean n-6 and n-3 PUFA percentages in plasma lipids are influenced by the mean intake of the population studied. Thus, the plasma level of a-linolenic acid in our sample (0.5-0.6%) is lower than that found in Japan (0.8-0.9%) (Kuriki et al, 2002(Kuriki et al, , 2003 or in United Kingdom (1.3-1.4%) (Rosell et al, 2005), reflecting the low a-linolenic acid intake of the French population (Astorg et al, 2004). At variance, the plasma linoleic acid levels reach values (30-35% of fatty acids) comparable to those found in United Kingdom (Rosell et al, 2005), Norway (Andersen et al, 1999), Japan (Kuriki et al, 2002(Kuriki et al, , 2003 or Costa-Rica (Kuriki et al, 2003;Baylin et al, 2005), reflecting the high intakes of linoleic acid in most world countries (4-6% of energy) (Simopoulos, 2002).…”

“…Thus, the plasma level of a-linolenic acid in our sample (0.5-0.6%) is lower than that found in Japan (0.8-0.9%) (Kuriki et al, 2002(Kuriki et al, , 2003 or in United Kingdom (1.3-1.4%) (Rosell et al, 2005), reflecting the low a-linolenic acid intake of the French population (Astorg et al, 2004). At variance, the plasma linoleic acid levels reach values (30-35% of fatty acids) comparable to those found in United Kingdom (Rosell et al, 2005), Norway (Andersen et al, 1999), Japan (Kuriki et al, 2002(Kuriki et al, , 2003 or Costa-Rica (Kuriki et al, 2003;Baylin et al, 2005), reflecting the high intakes of linoleic acid in most world countries (4-6% of energy) (Simopoulos, 2002). Plasma levels of long-chain n-3 PUFA in our sample are much higher than in populations eating no or little fish (Baylin et al, 2005;Rosell et al, 2005), similar to those found in Norway (Andersen et al, 1999), and lower than those found in countries with a high fish consumption such as Spain (Amiano et al, 2001) or Japan (Kuriki et al, 2002(Kuriki et al, , 2003.…”

“…At variance, the plasma linoleic acid levels reach values (30-35% of fatty acids) comparable to those found in United Kingdom (Rosell et al, 2005), Norway (Andersen et al, 1999), Japan (Kuriki et al, 2002(Kuriki et al, , 2003 or Costa-Rica (Kuriki et al, 2003;Baylin et al, 2005), reflecting the high intakes of linoleic acid in most world countries (4-6% of energy) (Simopoulos, 2002). Plasma levels of long-chain n-3 PUFA in our sample are much higher than in populations eating no or little fish (Baylin et al, 2005;Rosell et al, 2005), similar to those found in Norway (Andersen et al, 1999), and lower than those found in countries with a high fish consumption such as Spain (Amiano et al, 2001) or Japan (Kuriki et al, 2002(Kuriki et al, , 2003. In Europe, the French rank among the higher fish and seafood consumers, after the Spanish and the Scandinavians (Welch et al, 2002).…”

“…In these studies, the dietary intakes of long-chain n-3 fatty acids EPA and DHA were significantly correlated with their plasma levels (r ¼ 0.3-0.8), but the correlations were stronger in studies where the intakes are measured shortly after or before blood sampling (Andersen et al, 1999), especially in those using weighed dietary records (r ¼ 0.6-0.8) (Kuriki et al, 2002(Kuriki et al, , 2003. In our study, the weaker values of the correlations found (r ¼ 0.2-0.3) are likely due to the time shift between blood sampling (at baseline) and the fifteen 24-h records (up to 3 years after the beginning of the study).…”

“…Previous studies have assessed the relationships between the plasma levels of individual PUFA and their intakes measured a diet history (Amiano et al, 2001), a 7-day weighed dietary record during the week preceding blood sampling (Kuriki et al, 2002(Kuriki et al, , 2003, or a food-frequency questionnaire (Andersen et al, 1999). In these studies, the dietary intakes of long-chain n-3 fatty acids EPA and DHA were significantly correlated with their plasma levels (r ¼ 0.3-0.8), but the correlations were stronger in studies where the intakes are measured shortly after or before blood sampling (Andersen et al, 1999), especially in those using weighed dietary records (r ¼ 0.6-0.8) (Kuriki et al, 2002(Kuriki et al, , 2003.…”