Docosahexaenoic acid (DHA)

Docosahexaenoic acid (C22: 6n-3, DHA) is a long-chain polyunsaturated fatty acid enriched in phospholipids of marine origin fundamental for the formation and function of the nervous system, particularly the brain and the retina of humans. The common name for DHA, which is rarely used, is cervonic acid.

DHA is particularly important in brain development as there is a “DHA accretion spurt” during the last gestational period.

DHA is almost exclusively present in significant amount in diverse seafood (fish, shellfish, micro- and macroalgae and even some mammals). It is evident that there is at least a 10 fold range in content of DHA per portion (i.e. per serving) of seafood, with fatty fish able to provide as much as 1-1.75 g of DHA per portion. Examples of fatty fish are mackerel, salmon, trout, herring, tuna and sardines.

DHA is the most abundant n-3 LCPUFA (long-chain polyunsaturated fatty acids) in the central and peripheral nervous system, representing the major proportion of PUFAs in brain and retina. This fatty acid is present in large amounts in phospholipids of brain gray matter. DHA takes an important role in neurogenesis and synaptogenesis, particularly in fetal development and during the first two years of life.

The DHA found in the CNS is not produced de novo in mammals. Instead, it must be obtained from the diet or synthesized from the precursor fatty acid, alpha-linolenic acid (ALA, 18:3 n-3). ALA is the only omega-3 fatty acid that is defined as a dietary essential nutrient. It is synthesized in plants and in many lower organisms and is found in the human diet mainly as a component of green leaves, some nuts, seeds and vegetable oils, and foods made from or containing those ingredients.
Docosahexaenoic acid (DHA)