Omega-3 fatty acids, classified as polyunsaturated fatty acids, are examples of long chain fatty acids, and compose three main types – alpha-linolenic acid (ALA) – the base of all Omega-3’s, Docohexaenoic acid (DHA), and Eicosapentaenoic acid (EPA). ALA is primarily sourced from plant material, including nuts, flax seeds/oils, and leafy vegetables. EPA and DHA are derived from marine life, particularly oily fish, with consumption more beneficial to overall health
Once ingested, Omega-3 fatty acids spread through body tissue by merging with cell membranes. Omega-3 fatty acids impact visual and neurological health, coronary disease, inflammatory responses, mental/neurological illness, and bone/joint health.
Omega-3 fatty acids are of particular importance to both the brain and the eye. Phospholipids (molecules that create a barrier between the inside and outside of a cell), comprise nearly two-thirds of the brain, the fattiest organ in the human body. Of that, 40% are comprised of DHA. DHA aids in reducing inflammation in the brain, allowing it to maintain a healthy formation. EPA positively influences serotonin and acetylcholine levels in the brain, resulting in improved mood and memory.
Approximately 60% of the polyunsaturated fatty acids in the retina of your eye are also comprised of DHA. The outer membrane of the retina’s photoreceptors (convert light into signals/images) consists of approximately 30% fatty acids, mostly DHA. Omega-3’s may also aid in maintaining moisture content of the eyes, helping protect and keep your eyes healthy.
As previously surmised, Omega-3 fatty acids influence cognitive health, with large quantities involved in healthy neurological construction and operation. Consequently, numerous studies have investigated their effect on cognitive health during the aging process, particularly later-stage aging. Research concluded that levels of DHA decreased in the frontal cortex and hippocampus – the memory centre of the brain. As a key component of cell membranes, particularly in the brain, Omega-3 fatty acids are essential for cognitive health at all ages, but particularly as we age. As the human body cannot synthesise Omega-3’s, dietary intake, particularly of DHA and EPA, is crucial. As we age cellular function is disrupted, yet it has been shown that DHA and EPA consumption reduces this, resulting in improved cognitive function.
The Recommended daily intake (RDI) of Omega-3’s is 250-500mg, yet Australia’s average intake is only 150-190mg/day. Incorporating Omega-3 food sources into your daily diet is not difficult. While salmon is the most well-known source of Omega-3s, with one 150g serving of salmon containing over 500mg, there are other options. Oily fish such as sardines, herring, tuna and mackerel, nuts (walnuts) and seeds (flaxseeds, chia), flax/soybean/canola oils, and foods fortified with Omega-3’s are all viable options that will improve cognitive function. Even some vegetables, including kale, spinach, broccoli, and blue-green algae (yes – ALGAE!), contain Omega-3’s, although only in small amounts. As such, supplementation with fish or krill oil tablets would benefit those on a vegetarian diet or with limited access to oily fish sources. Viable fish sources should be accessible for most of the aging population, leading to cognitive clarity and improved overall wellbeing.