Benefits of Omega-3 DHA for the retina

Studies show that diets containing 9.5% Omega 3 DHA completely prevent the retinal degeneration caused by N methyl N nitrosourea. By contrast, diets containing only 4.75% DHA (EPA+DHA group) or only EPA did not have this protective effect.

(Biol Chem 2003;278:14677-14687)

 


Why is DHA the most suitable Omega-3 fatty acid?

 

DHA is the most abundant omega 3 fatty acid in the body because it is present in all the organs, especially the central nervous system, sperm and the retina. Normally, DHA content is between 5 and 30 times greater than that of EPA in the majority of organs. DHA is the fatty acid of greatest benefit to human health. It is essential to the cardiovascular system, to the development of the brain and children’s capacity for learning, to the eyes and nervous system, and to inflammatory situations, amongst other things.

Various studies have shown that sufficient DHA intake is crucial, but that there is not enough of it in our normal diet. The World Health Organisation (WHO) recommends a daily intake of 150 mg of DHA and EPA and the normal diet of people in more-southerly countries does not reach these levels, since it is found particularly in blue fish, and its consumtion has fallen dramatically the last decades.

Other international organizations recommend higher daily doses of DHA and EPA:
- International Society for the Study of Fatty Acids and Lipids (ISSFAL) 650 mg
- French Agency for Food Health and Safety (AFSSA) 500 mg
- British Nutrition Foundation (BNF) 1250 mg
- Danish Ministry of Health 300 mg

For DHA in particular, the daily intakes recommended by these organizations are:
- ISSFAL 325 mg (minimum 220)
- AFSSA 120 mg

¿Are there different types of Omega-3?

 

The 3 most important types of omega 3 fatty acid are:


- Alpha Linolenic acid (ALA)

- Eicosapentaenoic acid (EPA)

- Docosahexaenoic acid (DHA)


The body is capable of producing EPA and DHA from ALA. However, various studies have shown that administering ALA does not generate the quantities of DHA and EPA that are physiologically necessary.


As for administering DHA and EPA, the latest recommendations suggest that the most efficient way to increase concentrations of a given omega 3 fatty acid is to administer that acid specifically. However, in more general terms, administering DHA guarantees a basic concentration of EPA, while administering just EPA reduces the concentration of DHA.


Therefore, if we want to increase our DHA concentration, the best way is to give an organism a supplement that has a concentration of DHA with a small quantity of EPA. It should be remembered that the proportions of EPA and DHA contained in blue fish varies from species to species.

(Am J Clin Nutr 2006;84:5-17)

 


¿Why consume Omega-3?

 

It is now widely accepted by the scientific community that consumption of omega 3 fatty acids is beneficial to health in general. A large number of studies of omega 3 fatty acids in diet have demonstrated their importance.

Omega 3 fatty acids are naturally occurring in the human body, although generally not in sufficient quantities. Various pieces of basic, clinical and epidemiological research have reported significant advantages in consumption of omega 3 fatty acids in areas as diverse as cardiology, neurology, chronic inflammatory situations, ophthalmology, paediatrics, gynaecology, etc.

Omega 3 fatty acids are crucial to the brain’s development and functions.