Small portions (≈15–30 g) several times a week; an alternative to krill oil as a source of phospholipid DHA.
Phospholipid DHA crosses the blood-brain barrier via Mfsd2a (a specialized transporter); especially relevant in APOE4 carriers, in whom free DHA is poorly transported.
View the study (preclinical) →The phospholipid form of DHA may be more effective than that of conventional fish oil for brain development.
Mice without Mfsd2a have 60% less brain DHA, smaller brains, and progressive cognitive deficits.
View the study (preclinical) →*⏱ 2 min read
Salmon roe, sometimes called salmon caviar, is the mass of internal eggs found in female salmon; it is rich in protein, vitamins, astaxanthin, and the omega-3 fatty acids EPA and DHA, but what makes salmon roe especially interesting from the standpoint of brain health is not only the amount of DHA it contains but the chemical form in which it occurs: between 40% and 70% of the DHA in salmon roe is in phospholipid form, compared with fish, which has only 1-3%.
This difference in the chemical form of DHA matters because it determines how the fatty acid is transported to the brain: free DHA is transported across the outer membrane of the blood-brain barrier by passive diffusion, but the lysophospholipid form of DHA, DHA-lysoPC, is transported through a specialized protein transporter called Mfsd2a that penetrates the inner membrane of the barrier, offering a more direct and efficient route into brain tissue, especially in people with the APOE4 genetic variant, whose diffusion of free DHA is impaired.
Mice lacking the Mfsd2a transporter have 60% less DHA in their brains, have smaller brains, and typically exhibit a variety of motor and cognitive defects; infants who have a mutation in the gene that codes for this transporter develop microcephaly and exhibit early neurodegeneration that worsens progressively with age, which suggests that the transport of DHA-lysoPC to the brain may be important for maintaining brain function during the aging process and is especially relevant for people with the APOE4 variant.
The APOE4 variant disrupts the tight junctions of the blood-brain barrier, leading to a breakdown in the integrity of the outer barrier and impaired diffusion of free DHA, which puts people with this variant at higher risk of developing Alzheimer's; however, the metabolism and transport of DHA-lysoPC can bypass the tight junctions through the Mfsd2a transporter, providing a better transport route for DHA in people with the APOE4 variant and potentially reducing their risk of developing the disease, with salmon roe and krill oil being the richest dietary sources of DHA in phospholipid form.
Information, not medical advice. Scientific evidence reflects the quality of the studies.