Egg fortification with n-3 polyunsaturated fatty acids (PUFA): nutritional benefits versus high n-6 PUFA western diets, and consumer acceptance

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.

To evaluate the dietary contribution of 'field fortification' of eggs by adding n-3 PUFA to high n-6 PUFA hen feed and to assess whether it meets consumer preferences.

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.

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 (AA:DHA) 3.0-fold (P< 0.0003). Sensory evaluations were not significantly different. Egg cost increased by 1.5-3.0%. Fortified egg n-3 PUFA content averaged 14.3% of the current intake of Americans and 15.9% of Israelis - 9.8 and 10.6% of upper Dietary Reference Intakes, respectively. Egg DHA content averaged 33.7 and 41.4% 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.

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.