IMAJ | volume
Journal 4, April 2008
pages: 262-265
Summary
Background: As high dietary n-6 polyunsaturated fatty acids and n-6:n-3 PUFA ratio may contribute to many western ailments, increasing n-3 PUFA in foods could be beneficial. The nutritional significance of n-3 PUFA-fortified egg vs. enzymatically competitive high n-6 PUFA diets is debatable.
Objectives: To evaluate the dietary contribution of 'field fortification' of eggs by adding n-3 PUFA to high n-6 PUFA hen feed and whether it meets consumer preferences.
Methods: Laying hens (n=3500) were fed n-3 PUFA-fortified (5% extruded linseed) feed or standard (control) feed for 5 weeks. Nutritional significance was evaluated for western (American, Israeli) populations.
Results: Compared to regular (control) eggs, fortified eggs yielded a 3.8-fold increase in total n-3 PUFA, 6.4-fold alpha-linolenic acid (18:3), and 2.4-fold docohexaenoic acid 22:6). N-6:n-3 PUFA ratio decreased 3.6-fold, and n-6:n-3 long chain PUFA ratio threefold (P < 0.0003). Sensory evaluations were not significantly different. Egg cost increased by 1.0–1.5%. Fortified egg n-3 PUFA content averaged 14.3% of the current intake of Americans and 15.9% of Israelis – 9.8 and 10.5% of upper Dietary Reference Intakes, respectively. Egg DHA content averaged 32.9 and 41.1% of upper DRI. Current cholesterol intakes average 281 and 263 mg/day (median 214 and 184 mg/day) including 0.7 and 0.5 egg/day; reported hypercholesterolemia rates are 17.7 and 16.5%, respectively.
Conclusions: Effective concentration and transformation of supplemental n-3 PUFA/LCPUFA from feed to egg substantially enhanced egg n-3 PUFA %DRI, particularly of DHA, critical for health but often deficient. Such land-based n-3 PUFA/LCPUFA fortification may be applicable to high n-6 PUFA diets, fitting within cholesterol limitations and market criteria. It may contribute to general health and specific requirements (i.e., pregnancy and lactation), with possibilities of wide accessibility and standardization.
PUFA = polyunsaturated fatty acids
DRI = Dietary Reference Intake
LCPUFA = long chain PUFA (≥ C20)
DHA = docohexaenoic acid (22:6 n-3)