The highly unsaturated fatty acids: physiological role and clinical possibilities

  • M. Haag Departement Fisiologie, Universiteit van Pretoria, Posbus 2034, Pretoria 0001
  • M. Coetzee Departement Fisiologie, Universiteit van Pretoria, Posbus 2034, Pretoria 0001


Fatty acids play a very important role in human physiology. Except for the fact that fatty acids in stored triglycerides can be used for energy production, fatty acids from dietary lipids are transported in plasma and built into various cellular structures. The fatty acid profile of cell membrane phospholipids plays a determining role in the cell membrane in that it influences fluidity, receptor function and the type of eicosanoids that can be synthesised from it. Fatty acids also have highly differentiated inputs in cellular transduction mechanisms and regulation of gene transcription. In this, the steric conformation plays a large role: the straight-chain saturated and trans-fatty acids, when compared with the unsaturated fatty acids with progressively more bent chains, lead to a variety of mechanisms that have less positive effects on our health. In this regard, the two most important families of polyunsaturated fatty acids, the so-called omega-3 and omega-6 fatty acids, also lead to different effects. Changes in the pattern of dietary fatty acid intake through the ages have lead to an increased intake of saturated, trans- and omega-6 fatty acids relative to omega-3 fatty acids. Clinical trials during the past twenty years have shown that dietary supplementation with omega-3 fatty acids can lead to an improvement of the symptoms of certain lifestyleassociated disorders. Atherosclerosis, obesity, type 2 diabetes mellitus, depression, schizophrenia, Alzheimer’s disease, attention deficit hyperactivity disorder in young children, certain types of cancer, osteoporosis in the elderly and some dermatological disorders are amongst the conditions that can be addressed in this manner.
Original Research