Development and pilot testing of an omega-3 fatty acid food frequency questionnaire

Potential Neuroprotective Effects of Dietary Omega-3 Fatty Acids on Stress in Alzheimer's Disease

BACKGROUND

A large number of individual potentially modifiable factors are associated with risk for Alzheimer's disease (AD). However, less is known about the interactions between the individual factors.

METHODS

In order to begin to examine the relationship between a pair of factors, we performed a pilot study, surveying patients with AD and controls for stress exposure and dietary omega-3 fatty acid intake to explore their relationship for risk of AD.

RESULTS

For individuals with the greatest stress exposure, omega-3 fatty acid intake was significantly greater in healthy controls than in AD patients. There was no difference among those with low stress exposure.

CONCLUSIONS

These initial results begin to suggest that omega-3 fatty acids may mitigate AD risk in the setting of greater stress exposure. This will need to be examined with larger populations and other pairs of risk factors to better understand these important relationships. Examining how individual risk factors interact will ultimately be important for learning how to optimally decrease the risk of AD.

N-docosahexaenoylethanolamine detected in human breast milk

PURPOSE

Measure concentrations of the neurogenic, pro-neurogenic, pro-synaptogenic and anti-inflammatory mediator N-docosahexaenoylethanolamine (synaptamide) in relation to its precursor docosahexaenoic acid (DHA) in breast milk.

DESIGN AND METHODS

Postpartum women were recruited prior to discharge. We supplemented half the subjects with omega-3 fatty acids. Breast milk samples were collected at 1, 4 and 8 weeks. Synaptamide and DHA concentrations were determined by liquidchromatography/tandem mass spectrometry (LC-MS/MS) and gas chromatography, respectively.

RESULTS

Synaptamide was detected in all breast milk samples. The concentration ranged from 44 to 257 fmol/mL. Omega-3 fatty acid supplementation did not affect DHA or synaptamide concentration in breast milk due to a high-DHA-containing diet self-selected by control mothers. Nevertheless, synaptamide levels significantly correlated with DHA concentration in breast milk (r = 0.624, P < 0.001).

CONCLUSION

This is the first demonstration of detectable concentrations of synaptamide in human breast milk. Although the attempt to raise the milk DHA content by omega-3 fatty acid supplementation was not successful in the current study, the positive correlation observed between synaptamide and DHA concentration suggests that synaptamide levels in human milk can be raised by proper omega-3 fatty acid supplementation that is known to increase DHA.

Rheological characterization and stability study of an emulsion made with a dairy by-product enriched with omega-3 fatty acids

This study involved a rheological characterization of a W/O emulsion manufactured on a pilot scale using omega-3 fatty acids as part of the oil phase and butter milk as the emulsifier. Polyunsaturated omega-3 fatty acids are essential to prevent cardiovascular diseases, improve pulmonary function and also form part of the neurological structure. Buttermilk is a by-product of the dairy industry and has a high organic load which possesses surfactant properties and constitutes a good substitute for conventional emulsifiers in the food industry. The microstructural nature of the emulsion was characterized from the viscoelastic parameters and mechanical spectra. The linear viscoelastic range was determined, from which the maximum stress that the emulsion could withstand from the processing conditions without altering its microstructure was established. In addition, the storage stability of the emulsion was studied to instrumentally predict the rheological behaviour before sensory destabilization of the emulsion was observed. At the frequencies used, a significant decrease in dynamic viscoelastic parameters was periodically observed (G 'and G''), showing a structural change during storage. Furthermore, a coalescence phenomenon was observed after 18 months. The formulation with added omega-3 fatty acids and buttermilk provided a basis for obtaining a functional food as well as adding value to an industrial by-product.

Effect of droplet size on autoxidation rates of methyl linoleate and α-linolenate in an oil-in-water emulsion

Methyl linoleate and α-linolenate were used as representative n-6 and n-3 polyunsaturated fatty acid esters, respectively, to examine the effect of oil droplet size on autoxidative stability in oil-in-water systems. The emulsions, which were prepared via membrane emulsification and had a mean oil droplet size of approximately 1-30 μm, and had a stable size during the autoxidation of each substrate at 55°C. The autoxidation of methyl linoleate did not depend on oil droplet size during the entire process and that of methyl α-linolenate was independent of oil droplet size during the first half of the autoxidation process. However, the autoxidation rate of methyl α-linolenate proceeded faster in the emulsion with smaller oil droplet size during the last half of the autoxidation process.