- Arachidonic acid (ARA, C20:4) and docosahexaenoic acid (DHA, C22:6) are long chain polyunsaturated fatty acids (LCPUFAs).
- ARA can be added to infant formulas (in HOCHDORF infant formulas, this is added as Mortierella alpina oil). ARA can also be synthesised endogenously (produced within body) from the essential fatty acid linoleic acid (LA).
From ALA to DHA and from LA to ARA
- LA is the parent of the Ω/ω /omega-6 or n-6 family. LA is the precursor (forerunner) of ARA. ALA (α-linolenic acid) is the parent of the Ω/ω/omega-3 or n-3 family and precursor of DHA.
- LA is converted via α-linolenic acid (gamma-linolenic acid, GLA) with the help of specific enzymes and via various other fatty acids into the LCPUFA arachidonic acid (ARA). ALA is converted via eicosapentaenoic acid (EPA) with the help of specific enzymes and via various other fatty acids into the LCPUFA docosahexaenoic acid (DHA).
- For the conversion, both families (omega-3 and omega-6) use the same enzymes (e.g. elongase), resulting in competition between the two families. In order to produce the required amount of DHA and ARA, the right balance (good ratio) between ALA and LA is important – e.g. a diet rich in LA reduces ALA conversion. Thus, high-LA levels in the diet generally result in low n-3 LCPUFA status.
- There is no specific regulation (EU regulation 2016/127) for the ALA/LA ratio. To promote an efficient conversion a low ratio is nutritionally recommended (range: 1:5 – 1:15).
New regulation: DHA now mandatory and ARA optional in IF and FOF
- Due to insufficient activity of the conversion enzymes, the rate of conversion ALA to DHA and LA to ARA is low – especially in early infancy. DHA and ARA levels depend, to a great extent, on dietary intake.
- Due to the rapid brain and nerve growth in early infancy, the level of DHA and ARA synthesis may be inadequate to keep up with the demand. Therefore, supplementation of IF and FOF with LCPUFAs is now widely recommended.
- The recent revision of the European legislation (EU regulation 2016/127) stipulates that all IF and FOF must contain DHA; formulas without DHA content will not be permitted in the European Union once this legislation is implemented.
- The addition of ARA is optional but is justified from an ethical nutritional point of view in line with the latest scientific insights.